AFAR Communications 24027 Wireless Ethernet Bridge User Manual 373526

AFAR Communications, Inc Wireless Ethernet Bridge 373526

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User Manual

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AR24027
Operator’s Manual
Rev: A
September, 2003
AFAR Communications Inc.
81 David Love Place
Santa Barbara, CA 93117
Tel: (805) 681 1993
Fax: (805) 681 1994
FCC Notice
This equipment has been tested and found to comply with the limits for a Class B digital
device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide
reasonable protection against harmful interference in a residential installation. This
equipment generates, uses, and can radiate radio frequency energy and, if not installed and
used in accordance with the instructions, may cause harmful interference to radio
communications. However, there is no guarantee that interference will not occur in a
particular installation. If this equipment does cause harmful interference to radio or television
reception, which can be determined by turning the equipment off and on, the user is
encouraged to try to correct the interference by one or more of the following measures:
• Reorient or relocate the receiving antenna.
• Increase the separation between the equipment and receiver.
• Connect the equipment into an outlet on a circuit different from that to which the
receiver is connected.
• Consult the dealer or an experienced radio/TV technician for help.
Changes or modifications not expressly approved in writing by AFAR Communications Inc.
may void the user’s authority to operate this equipment. AFAR Communications Inc. can not
accept any financial or other responsibilities that may be the result of your use of this
information, including direct, indirect, special, or consequential damages. Refer to warranty
documents for product warranty coverage and specifics.
AR24027 Operator’s Manual (rev E)
STATEMENT OF WARRANTY
AFAR COMMUNICATIONS INC. products, except as otherwise stated in an applicable price list, are warranted against
defects in workmanship and material for a period of one (1) year from date of delivery as evidenced by AFAR
COMMUNICATIONS INC.’s packing slip or other transportation receipt.
AFAR COMMUNICATIONS INC.’s sole responsibility under this warranty shall be to either repair or replace, at its option,
any component which fails during the applicable warranty period because of a defect in workmanship and material, provided
PURCHASER has promptly reported same to AFAR COMMUNICATIONS INC. in writing. All replaced Products or parts
shall become AFAR COMMUNICATIONS INC.’s property.
AFAR COMMUNICATIONS INC. shall honor the warranty at AFAR COMMUNICATIONS INC.’s facility in Goleta,
California. It is PURCHASER’s responsibility to return, at its expense, the allegedly defective Product to AFAR
COMMUNICATIONS INC. PURCHASER must notify AFAR COMMUNICATIONS INC. and obtain shipping
instructions prior to returning any Product. Transportation charges for the return of the Product to PURCHASER shall be
paid by AFAR COMMUNICATIONS INC. within the United States. For all other locations, the warranty excludes all costs
of shipping, customs clearance and other related charges. If AFAR COMMUNICATIONS INC. determines that the Product
is not defective within the terms of the warranty, PURCHASER shall pay AFAR COMMUNICATIONS INC. all costs of
handling, transportation and repairs at the prevailing repair rates.
All the above warranties are contingent upon proper use of the Product. These warranties will not apply (i) if adjustment,
repair, or parts replacement is required because of accident, unusual physical, electrical or electromagnetic stress, negligence
of PURCHASER, misuse, failure of electric power environmental controls, transportation, not maintained in accordance
with AFAR COMMUNICATIONS INC. specifications, or abuses other than ordinary use (ii) if the Product has been
modified by PURCHASER or has been repaired or altered outside AFAR COMMUNICATIONS INC.’s factory, unless
AFAR COMMUNICATIONS INC. specifically authorizes such repairs or alterations; (iii) where AFAR
COMMUNICATIONS INC. serial numbers, warranty date or quality assurance decals have been removed or altered.
AFAR COMMUNICATIONS INC. also reserves the right to make product improvements without incurring any obligation
or liability to make the same changes in Products previously manufactured or purchased. In no event shall AFAR
COMMUNICATIONS INC. be liable for any breach of warranty in an amount exceeding the net selling price of any
defective Product. No person, including any dealer, agent or representative of AFAR COMMUNICATIONS INC. is
authorized to assume for AFAR COMMUNICATIONS INC. any other liability on its behalf except as set forth herein.
Nonpayment of any invoice rendered within the stated payment terms automatically cancels any warranty or guarantee
stated or implied. If any payment is due AFAR COMMUNICATIONS INC. for services performed hereunder, it shall be
subject to the same payment terms as the original purchase.
AFAR COMMUNICATIONS INC. HEREBY DISCLAIMS ALL IMPLIED WARRANTIES OF PRODUCTS
INCLUDING WITHOUT LIMITATION, ALL IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR
A PARTICULAR PURPOSE. The warranties expressly stated herein are the sole obligation or liability on the part of
AFAR COMMUNICATIONS INC. arising out of or in connection with the sale or performance of the products.
Products Manufactured by Others - For the products not manufactured by AFAR COMMUNICATIONS INC. the original
manufacturer’s warranty shall be assigned to PURCHASER to the extent permitted and is in lieu of any other warranty,
express or implied. For warranty information on a specific product, a written request should be made to AFAR
COMMUNICATIONS INC..
IN NO EVENT WILL AFAR COMMUNICATIONS INC. BE LIABLE TO PURCHASER FOR (i) FOR
REPROCUREMENT COSTS; (ii) SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES; (iii) ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS ARISING OUT OF OR IN CONNECTION
WITH THIS AGREEMENT, OR THE USE OF PERFORMANCE OF AFAR COMMUNICATIONS INC. PRODUCTS,
REGARDLESS OF WHETHER THE CAUSE OF ACTION IS IN CONTRACT, TORT, INCLUDING NEGLIGENCE,
OR ANY OTHER FORM.
No action, whether in contract or tort, including negligence, arising out of or in connection with this Agreement, may be
brought by either party more than eighteen (18) months after the cause of action has accrued, except that an action for
nonpayment may be brought within eighteen (18) months of the date of last payment.
- iii -
AR24027 Operator’s Manual (rev A)
- iv -
AR24027 Operator’s Manual (rev E)
TABLE OF CONTENTS
INTRODUCTION ........................................................................................................................................1
PRODUCT DESCRIPTION........................................................................................................................3
2.1
RADIO COMPONENTS ..............................................................................................................................3
2.2
RADIO CONNECTORS ...............................................................................................................................3
2.3
POWER INSERTER UNIT ...........................................................................................................................4
2.4
OUTDOOR INTERCONNECT CABLE ...........................................................................................................6
ANTENNAS, SITE SELECTION, PATH ANALYSIS.............................................................................9
3.1
INTRODUCTION ........................................................................................................................................9
3.2
SELECTING ANTENNA TYPE ....................................................................................................................9
3.2.1
Directionality................................................................................................................................10
3.2.2
Gain ..............................................................................................................................................10
3.2.3
Polarization ..................................................................................................................................11
3.3
SITE SELECTION ....................................................................................................................................11
3.3.1
Line-of-Sight Path.........................................................................................................................12
3.3.2
Radio Horizon (Maximum Line-of-Sight Range) ..........................................................................12
3.3.3
Point-to-Point Path Analysis ........................................................................................................13
3.3.4
Antenna Orientation .....................................................................................................................19
3.3.5
Cable Loss (Attenuation) ..............................................................................................................19
3.3.6
Connector Loss .............................................................................................................................20
3.3.7
Other Considerations – Antenna Grounding................................................................................20
INSTALLATION AND SETUP ................................................................................................................23
4.1
BENCH CHECK OUT (USING RADIO ETHERNET CONNECTION)................................................................23
4.2
BENCH CHECK OUT (USING RADIO AUXILIARY PORTS)..........................................................................24
4.3
FIELD INSTALLATION ............................................................................................................................25
4.3.1
Configuration ...............................................................................................................................25
4.3.2
Antenna Installation .....................................................................................................................26
4.3.3
Antenna Alignment .......................................................................................................................27
4.3.4
Spectrum Analysis and channel selection .....................................................................................27
4.3.5
Output Power Limits (FCC) .........................................................................................................28
4.3.6
Output Power Limits (CE) ............................................................................................................28
4.3.7
Maximum Permissible Exposure (MPE) Limitations....................................................................29
4.4
ETHERNET BRIDGING ............................................................................................................................29
4.5
UPGRADING THE FIRMWARE. ................................................................................................................30
4.5.1
Description ...................................................................................................................................30
4.5.2
Installing new firmware through the Ethernet port ......................................................................31
4.5.3
Installing new firmware using Telnet ...........................................................................................33
4.5.4
Installing new firmware using the RS-232 serial port ..................................................................34
4.5.5
Feature upgrades..........................................................................................................................35
COMMANDS..............................................................................................................................................37
5.1
CONFIGURATION TECHNIQUES...............................................................................................................37
5.2
COMMAND SYNTAX ...............................................................................................................................37
5.3
CONFIGURATION MANAGEMENT COMMANDS .......................................................................................39
5.4
MAJOR CONFIGURATION PARAMETERS .................................................................................................41
5.5
BRIDGE MANAGEMENT COMMANDS .....................................................................................................43
5.6
INTERNET PROTOCOL (IP) MANAGEMENT COMMANDS .........................................................................44
5.7
INSTALLATION AND LINK MONITORING COMMANDS ............................................................................46
5.8
EVENT LOGGING COMMANDS ...............................................................................................................48
5.9
FILE UTILITIES ......................................................................................................................................49
5.10 MISCELLANEOUS COMMANDS ...............................................................................................................51
NETWORK MANAGEMENT..................................................................................................................55
6.1
TELNET .................................................................................................................................................55
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AR24027 Operator’s Manual (rev A)
6.1.1
General ........................................................................................................................................ 55
6.1.2
Starting a Telnet Session.............................................................................................................. 55
6.1.3
Telnet Security ............................................................................................................................. 56
6.2
SNMP .................................................................................................................................................. 56
6.2.1
Command Line Interface Versus SNMP ...................................................................................... 56
6.2.2
What is SNMP?............................................................................................................................ 57
6.2.3
Security Considerations in SNMP ............................................................................................... 57
6.2.4
Examples of Network Management Systems ................................................................................ 57
6.2.5
AR24027 Management Information Base (MIB) ......................................................................... 58
APPENDIX A - SPECIFICATIONS................................................................................................................ 59
APPENDIX B – CHANNEL FREQUENCY ASSIGNMENT ....................................................................... 61
APPENDIX C – ETHERNET CONSOLE PROGRAM ................................................................................ 63
APPENDIX D – INTERCONNECT CABLES .................................ERROR! BOOKMARK NOT DEFINED.
- vi -
AR24027 Operator’s Manual (rev E)
1 INTRODUCTION
The AR24027 Wireless Ethernet Bridge is a license free radio that can be used to bridge Ethernet
LAN’s (Local Area Networks) across distances ranging from a few hundred feet to 50 miles (80 Km)
and beyond. In a standalone configuration the radio provides an Ethernet interface to the user. It can
also be paired with the Afar NetCrossing™ Gateway (NX2048), to provide a full duplex synchronous
serial stream connection, in addition to the Ethernet interface, between the two end points.
The AR24027 is a Spread Spectrum radio operating in the “Industrial Scientific and Medical” (ISM)
band from 2.400GHz to 2.4835 GHz. It is designed from the ground up to provide a robust link under
very adverse conditions, often encountered in this unlicensed band. This includes the following
features:
1. All the electronics are housed in an environmentally sealed enclosure rated for outdoor
installation. You can mount the unit in close proximity to the antenna, which increases system
performance by avoiding RF cable losses or expensive rigid coax cables.
2. The radio RF bandwidth is much narrower than other unlicensed devices in the 2.4 GHz band.
This has several advantages, namely (i) the radio sensitivity is greatly improved allowing longer
ranges, (ii) there is a much larger number of non-overlapping channels to choose from, and (iii) it is
much easier to find an unused gap in a crowded spectrum.
3. For long range links in a crowded spectrum the most desirable receive frequencies at each end of
the link are often different. In the Afar radio the transmit and receive frequencies can be selected
independently of each other.
4. The radio incorporates spectrum analysis and timing analysis tools, which allow the operator to
quickly perform a survey of the RF environment without the need for expensive or heavy spectrum
analyzers.
5. Unique antenna alignment aid provides audio feedback proportional to the RSSI, freeing the
installer’s hands to adjust and tighten the antenna without having to hold or look at other
instrumentation.
The radio implements a transparent bridge algorithm, where each unit automatically learns the
addresses of all stations in the network and forwards over RF only the traffic that needs to be
delivered to the remote unit. This reduces the RF throughput required by the radio. If the radio is
used standalone, an indoor “power inserter” unit combines the power and Ethernet data into a single
CAT5 cable connected to the radio.
If the application requires a serial synchronous interface, the radios can be paired with the Afar
NetCrossing™ Gateway to provide both an Ethernet and a serial link of up to 1.024 Kbps across the
same wireless connection. In this case the NetCrossing™ Gateway provides both the power and data
to the radio across the single CAT5 cable. Refer to the NetCrossing™ Gateway Operator’s Manual
for complete details.
The radios operate in Time Division Duplex (TDD) mode using a configurable size time slot. One
advantage of TDD operation is that the radios can synchronize their transmissions such that all colocated radios transmit at the same time, thereby avoiding self-generated interference. This technique
allows deploying a star network with 30 or more radios at the same location.
-1-
AR24027 Operator’s Manual (rev A)
The AR24027 can be configured over a local serial interface or over the Ethernet using an “Ethernet
console” program provided by Afar. Once a unit is configured with an IP address you can also
configure and monitor the unit using Telnet or SNMP. The radio firmware in non-volatile memory
can also be updated remotely.
-2-
AR24027 Operator’s Manual (rev E)
2 PRODUCT DESCRIPTION
2.1 Radio Components
Table 2.1 below shows the components that are typically shipped with each AR24027 radio.
Table 2.1 - AR24027 Components
AR24027 outdoor unit.
Bracket for securing the AR24027 unit to an outdoor mast.
Power Inserter Module including 110-240 VAC power supply
CD with this Operator’s Manual, Econsole program, and other application notes.
CAT 5 cable for connection between AR24027 radio and power inserter module (1)
Auxiliary port cable for RS-232 connection (1)
Auxiliary port cable with Audio jack for antenna alignment (1)
1 Not supplied with standard radio kit. Available from AFAR as optional equipment.
2.2 Radio Connectors
Figure 2.1 shows the AR24027 radio mounted on a mast. The radio is housed in a rectangular
enclosure with two N-female connectors at the top for connection to RF antennas, and two special
purpose connectors, at the bottom, for DC power, Ethernet data and control.
Figure 2.1
The function of each connector is described in the table below.
-3-
AR24027 Operator’s Manual (rev A)
Table 2.2 – AR24027 Connectors
CONNECTOR
TYPE
Function
N-FEMALE
2.4 GHz RF connector to antenna A
N-FEMALE
2.4 GHz RF connector to antenna B
Lumberg
Auxiliary port (3 pin) used as an antenna alignment aid and
for RS-232 console port.
Lumberg
10/100 Base-T data interface and DC power input (8 pin).
Must be connected to the “Power Inserter Unit” with a CAT
5 cable.
An eight conductor CAT 5 cable must be connected between the AR24027 and the Power Inserter
Unit. The wiring for this cable is shown in figure 2.3.
Table 2.3 shows the pin assignment of the three pin, auxiliary port connector. The unit is shipped
with a cover in this connector. The connector can be used during installation as a console port and
also as an audio antenna alignment aid. AFAR has available two cables to convert from this nonstandar 3-pin connector to either a DE-9 connector (for RS-232 console) or to a standard audio jack
(for connection to a headphone). See Appendix D for cable diagrams.
Table 2.3 – Auxiliary Port Connector Pin Assignments
Pin
Signal Name
Abbr.
Direction
Receive Data
RD
Radio Output
Transmit Data
TD
Radio Input
Ground
GND
2.3 Power Inserter Unit
The Power Inserter Unit includes a power supply for connection to an AC outlet, two RJ45
connectors and a bi-color LED. The two RJ-45 connectors are labeled “To LAN” and “To radio”.
The following tables describe those connectors.
-4-
AR24027 Operator’s Manual (rev E)
Table 2.4 – Power Inserter Unit
Connector/LED
Type
Function
To LAN
RJ-45
10/100 Base-T to be connected to the Local Area Network. Use a
straight through cable to connect to a hub and a cross over cable
to connect directly to a computer. See table 2.5 for pin
assignments.
To radio
RJ-45
Carries the DC power and Ethernet signals to the AR24027. See
table 2.6 for pin assignments.
LED
Amber/
Green
Amber: Indicates that the power inserter unit has DC power
from the wall supply but no power is being drawn by the
AR24027.
Green: Indicates that the AR24027 is drawing power.
WARNING
The Power Inserter connector labeled “To radio” includes DC voltage in two of the pins. It must not
be connected to a LAN as this voltage may damage some LAN cards.
Table 2.5 – “To LAN” Ethernet Connector Pin Assignments
Pin
Signal Name
Abbr.
Ethernet Tx
Tx (+)
Radio to Ethernet
Ethernet Tx
Tx (-)
Radio to Ethernet
Ethernet Rx
Rx (+)
Ethernet to Radio
(not connected)
(not connected)
Ethernet Rx
Rx (-)
Ethernet to radio
(not connected)
(not connected)
-5-
Direction
AR24027 Operator’s Manual (rev A)
Table 2.6 – “To radio” Ethernet Connector Pin Assignments
Pin
Signal Name
Abbr.
Ethernet Tx
Tx (+)
Radio to Ethernet
Ethernet Tx
Tx (-)
Radio to Ethernet
Ethernet Rx
Rx (+)
Ethernet to Radio
+18 VDC
DCV (+)
Power Inserter to Radio
+18 VDC
DCV(+)
Power Inserter to Radio
Ethernet Rx
18 VDC ground
GND(-)
Power Inserter to Radio
18 VDC ground
GND(-)
Power Inserter to Radio
Rx (-)
Direction
Ethernet to Radio
2.4 Outdoor Interconnect Cable
The interconnect cable between the Power Inserter Unit and the AR24027 carries the following
signals
1. DC voltage to supply power to the AR24027.
2. 10/100 Base-T Ethernet data.
Both these signals are carried in a single CAT 5 cable. The system is designed to allow cable lengths
up to 100 meters (300 feet). Figure 2.3 shows the interconnect diagram for this cable and connector
types. Table 2.7 lists a few part numbers and sources of appropriate CAT 5 cable for this application.
AFAR Communications Inc. carries several pre-made cables of different lengths. See Appendix D
for connector diagrams, part numbers, and assembly instructions.
RJ 45 MALE
Lumberg
RADIO_ETH_TX+
RADIO_ETH_TX-
RADIO_ETH_RX+
VDC
VDC
RADIO_ETH_RX-
GND
GND
Figure 2.3 – CAT 5 Outdoor Interconnect cable diagram
-6-
AR24027 Operator’s Manual (rev E)
Table 2.7 – Indoor/Outdoor Unit CAT 5 cable
Part number
Manufacturer
Description
04-0010-34
Superior Essex
Industrial shielded, weatherproof cable for direct
burial, aerial and other severe environments
18-241-31(gray)
18-241-11 (beige)
Superior Essex
Unshielded outdoor rated cable
5EXH04P24-BK-RCMS-PV
CommScope
Unshielded outdoor rated cable
2137113 (ivory)
2137114 (gray)
General Cable
Unshielded outdoor rated cable
Belden
Unshielded outdoor rated cable
BC1002
-7-
AR24027 Operator’s Manual (rev E)
3 ANTENNAS, SITE SELECTION, PATH ANALYSIS
3.1 Introduction
NOTE
Basic instructions for connecting the antenna to the radio are given in
section 4. If the system is to be used at short to moderate ranges and
there are no major obstructions between antennas, the more detailed
information in this section may not be necessary.
Because AR24027 radios communicate with each other by means of radio waves, all aspects of
antenna installation affect their performance significantly, namely:
•
antenna type used
•
clear line-of-sight path between antennas
•
antenna orientation
•
antenna placement
•
antenna-to-antenna distance between radios
•
distance between the radio and its antenna (antenna cable length)
Therefore antenna installation is a vital part of system installation. Improper installation may greatly
reduce system performance, possibly rendering the system inoperable.
This section discusses these issues and provides guidelines for selecting antenna type, selecting
antenna location, and achieving an optimally functioning installation.
3.2 Selecting Antenna Type
There are a vast number of antenna types designed for various general and special purposes, but
despite the huge variety, all designs essentially address two concerns, directionality and gain. These
selection criteria are discussed in the following paragraphs, along with a third criterion, polarization.
For the AR24027, the three antenna types listed below will fulfill most installation requirements.
Antenna Type
Gain
AFAR Model Number
Omnidirectional
9 dBi
ATO-2409-000
Panel
18 dBi
ATD-2418-000
Semi-Parabolic
24 dBi
ATD-2424-000
-9-
AR24027 Operator’s Manual (rev A)
3.2.1
Directionality
An antenna may be designed to receive and transmit in all directions. Such antennas are
omnidirectional. An example of an omnidirectional receiving antenna would be a television antenna
in a metropolitan area where each television station transmits its signal from a different location
relative to the receiver. Similarly, a centrally located television transmitter would use an
omnidirectional transmitting antenna.
The sensitivity and power of an omnidirectional antenna are unfocused; that is, they are spread
through a wide volume of space, so the advantage of being able to communicate in all directions is
traded off for limited sensitivity and power.
If it is determined that all signals of interest are coming from a definable direction, the
omnidirectional antenna can be replaced by a directional or sectoral antenna, which increases
sensitivity and power by focusing the beam in the desired direction.
In practice, even omnidirectional antennas take advantage of directionality by focusing their
sensitivity and power in the horizontal plane. Rather than waste performance by sending signals into
space or into the ground, the horizontal omnidirectional antenna redirects its power and sensitivity
from these directions, increasing performance in the horizontal plane.
In point-to-point applications, where the direction of communication is known and fixed, a highly
focused directional antenna can be used to provide maximum sensitivity and power. In addition,
because of its decreased sensitivity in all directions but the desired one, the directional antenna
improves performance by rejecting signals not coming from the desired direction. This provides an
effective increase in signal-to-noise performance.
A sector antenna has a wider “spread” than a directional (generally between 60 to 120 degrees) which
makes it a cross between an omnidirectional and a directional. This is useful in a point to multipoint
configuration where multiple sites are grouped in the same general area. The installer can then make
use of the higher sensitivity and power but also take advantage of the wider beam pattern and
improved front to back ratio.
3.2.2
Gain
“Gain” specifies the receive and transmit performance of any antenna compared to a standard
omnidirectional antenna (“spherical radiator”). The objective of a directional antenna design is to
achieve gain, improving sensitivity and effective radiating power to increase range or data rate.
Gain is measured and stated in decibels, abbreviated dB. The decibel is a unit used to indicate the
relative difference in power between two signals. For example, a signal 3 dB greater than another
signal has twice as much power. The decibel is a logarithmic unit so each doubling of decibels
represents a fourfold increase in power. Since 3 dB represents a doubling of power, 6 dB represents a
fourfold power increase, 12 dB represents a 16-fold increase, etc. For antenna performance, the unit
used is dBi, “i” standing for “isotropic,” which describes the standard spherical radiation pattern.
One type of directional antenna available from AFAR Communications Inc. is called a “semi
parabolic”. This antenna has a gain of 24 dBi, representing power and sensitivity levels 256 times
greater than those of a standard omnidirectional antenna.
- 10 -
AR24027 Operator’s Manual (rev E)
For omnidirectional coverage from fixed locations, AFAR Communications Inc. provides collinear
antennas. The collinear design achieves gain by increased focus in comparison with the dipole
design. The standard collinear antenna used with the AR24027 provides 9 dBi gain, representing an
eight-fold power and sensitivity increase.
3.2.3
Polarization
Another important concept for antenna performance is polarization. An antenna radiates radio waves
that vibrate in a specific plane, normally horizontal or vertical. Polarization refers to the restriction of
wave vibration to a single plane.
NOTE
Do not confuse polarization with directionality. The plane of wave
vibration has nothing to do with the direction of wave propagation.
For example, an antenna that focuses its energy in the horizontal
plane may be vertically or horizontally polarized.
Designs such as the semi parabolic offer a choice of polarization. Mounting a semi parabolic antenna
with the elements horizontal provides horizontal polarization, while mounting the antenna with the
elements vertical provides vertical polarization. Similarly, the orientation of the radiating element of
the parabolic antenna determines polarization.
In setting up the AR24027 system, either vertical or horizontal polarization can be used, as long as
polarization is the same at both ends of each link. For any given pair of line-of-sight antennas, it is
essential that they both have the same polarization. Differences in polarization among antennas –
called “cross-polarization” – can reduce signal considerably.
3.3 Site Selection
At the high operating frequencies of the AR24027 system, radio waves travel in a nearly straight lineof-sight path. This is in contrast to the lower-frequency radio waves used for AM broadcasting.
These waves bounce between the ionosphere and the earth’s surface to travel long distances and
operate over and around obstructions. Higher-frequency radio waves do not behave in this manner
and are greatly weakened by substantial obstructions or the absence of a direct path. Simply put, all
antennas communicating with each other in the radio network must be able to physically “see” each
other.
For this reason, a proper antenna site must meet the following criteria:
1. For optimum performance at maximum range, there must be a clear line-of-sight path among all
antennas that communicate directly with each other. At shorter ranges, some degree of
obstruction may be tolerated, but performance in the presence of obstruction is difficult to predict.
2. Elevating one or more of the antennas in the system increases maximum line-of-sight range,
called the radio horizon. If antennas are located at a greater range than the ground-level radio
horizon, a means must be available for elevating the antennas.
3. All antennas must be properly oriented, and a directional antenna must be carefully aimed at its
target antenna to ensure communication at maximum range.
- 11 -
AR24027 Operator’s Manual (rev A)
4. All antenna cables attenuate (reduce) signal strength in proportion to their length. Therefore, the
distance between the antenna and the radio is limited to a cable length that does not exceed the
maximum attenuation tolerated by the system. Since various cable types offer different
attenuation levels, maximum length depends on cable type. Generally speaking, because the
AR24027 is an outdoor unit with the output port connected directly to the antenna, cable losses
are negligible and the radio will compensate, but there are limits to this compensation. See table
3-2 for sample cables and their respective attenuation values.
Each of these criteria is discussed at greater length in the following paragraphs.
3.3.1
Line-of-Sight Path
Because high-frequency radio waves are attenuated by obstructions, a clear line-of-sight path between
antennas is required for optimum performance at maximum range. For shorter ranges, a degree of
obstruction may be acceptable. For example, at less than maximum ranges the radio has some ability
to “penetrate” trees and other foliage. On the other hand, geographical features (hills) and large
buildings are likely to interfere with communications, and antennas must be elevated to “see” each
other above such objects.
Because of the uncertainties of radio communication, it is difficult to predict the results in conditions
where obstructions exist. The only valid advice is to try the proposed configuration and be prepared
to move or elevate the antennas.
3.3.2
Radio Horizon (Maximum Line-of-Sight Range)
In visual terms, the horizon is the point in the distance where an object drops out of sight because it is
blocked by the earth’s curvature. If the observer or object is elevated, the visual horizon is extended,
that is, the object can be seen at a greater distance before it drops out of view.
The same concept applies to radio signals: The radio horizon is the point in the distance where the
path between two antennas is blocked by the curvature of the earth. Like the visual horizon, the radio
horizon can be extended by elevating the transmitting antenna, receiving antenna, or both to extend
communication range.
The radio horizon can also be extended or shortened by certain phenomena such as refraction due to
atmospheric density and temperature inversions. Fog and rain, which reduce signal strength, can also
shorten the radio horizon although in the ISM band, this loss is negligible.
A reasonable approximation of the radio horizon based on antenna height can be obtained from the
graph in figure 3-1. (Note that this graph does not take atmospheric effects into account.) To use the
graph, set a straight edge so that it crosses the height of one of the antennas in the column on the left
and the height of the other antenna in the column on the right. The radio horizon in miles/km is
shown where the straight edge crosses the center column.
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AR24027 Operator’s Manual (rev E)
Figure 3-1. Antenna Height and Radio Horizon Graph
If the radio horizon is well within maximum communication range of the system, this graph provides
a reasonable guide for antenna height. However, as maximum range of the system is approached,
results are less reliable because of atmospheric effects and other unpredictable phenomena. In such
cases, the more thorough point-to-point path analysis described in the next section should provide
more reliable results.
3.3.3
Point-to-Point Path Analysis
A full point to point analysis should consist of at a minimum, a background noise evaluation of all
locations where radios are to be installed, a determination of the minimum antenna height required to
obtain a “line-of-sight”, and a calculation of the expected RSS level to be received at each of the
locations. The background noise measurement is critical as it gives the operator a preview of the
potential performance variations and the feasibility of utilizing a particular radio at a location. For
example, if the background noise is found to be at the same level as the radio sensitivity (when set to
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AR24027 Operator’s Manual (rev A)
maximum speed), a tradeoff analysis can be conducted before installation to determine if lowering the
data rate will allow the radio sufficient link margin to operate. A line-of-sight is required to insure
the best performance from the radio. The calculations below will allow the operator to build towers
and other mounting areas to the correct height before the antennas are installed. The calculation of
the RSS level is useful for two purposes. The first and primary purpose to calculate the theoretical
RSS level at the receive radio is to determine the link margin at the site. This information, when
coupled with the background noise measurement, will tell the operator if a link can be established and
give a reasonable “a priori” estimate of the performance of the system. In addition to this, the RSS
level allows the operator to do a quick check on the integrity of the system installation by verifying
that the received RSS level is close to the calculated value.
A background scan is easily accomplished using the built in Spectrum Analysis tool of the AR24027.
This should be done before any installation of any equipment is completed.
Although the graph of figure 3-1 provides a useful guide to antenna height requirements, a more
accurate determination of those requirements can be obtained by means of the analysis described in
the following steps.
NOTE
Computer programs available from many vendors can perform
portions of this procedure.
Requirements for this procedure are:
1. A topographical map of the installation site.
2. Graph paper, ten divisions per inch or equivalent metric scale
3. Straight edge
4. Calculator
Procedure:
1. On the topographic map, lot the precise location of each antenna site.
2. Draw a line between the sites; this line is the radio path.
3. On the graph paper, establish a vertical axis for elevation and a horizontal axis for distance. It is
usually easiest to make the vertical axis in feet or meters and the horizontal axis in miles or
kilometers.
4. Following the radio path line on the map, identify all obstructions. Most topographical maps
identify geographic information, such as hills and lakes, only. However, vegetation, buildings or
other structures that will interfere with radio transmissions must also be included.
5. Plot each obstruction on the graph, marking its elevation and distance from the sites. For dense
vegetation such as forests, add 40 to 60 feet (12 to 18 m) to the ground elevation.
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AR24027 Operator’s Manual (rev E)
An additional increment must be added to the height of each obstruction because of the earth’s
curvature. For each obstruction calculate this increment using the following formula:
d=
d1 × d2 × C
Where:
(for US units:)
d1
d2
(or for metric units:)
d1
d2
additional height increment in feet
distance of the obstruction from the first site in miles
distance of the obstruction from the second site in miles
.667 for US units
refractive index (use a value of 1.33).
additional height increment in meters
distance of the obstruction from the first site in km
distance of the obstruction from the second site in km
.079 for metric units
refractive index (use a value of 1.33).
Add the “d” value to the height of each obstruction plotted on the graph.
Another increment must be added to the height of each obstruction because of the Fresnel zone (The
required increment is 60% of the first Fresnel zone radius). For each obstruction calculate the
increment using the formula:
d=C
d1 × d2
F×D
Where:
(for US units:)
d1
d2
(or for metric units:)
d1
d2
60% of the first Fresnel zone radius in feet
distance of the obstruction from the first site in miles
distance of the obstruction from the second site in miles
1368 for US units
2400 (frequency in MHz)
total path length in miles (d1 + d2).
60% of the first Fresnel zone radius in meters
distance of the obstruction from the first site in km
distance of the obstruction from the second site in km
259 for metric units
2400 (frequency in MHz)
total path length in km (d1 + d2).
Add the “d” value to the height of each obstruction plotted on the graph.
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AR24027 Operator’s Manual (rev A)
Determine ideal antenna height by drawing a line on the graph between the sites and across the top of
the obstruction heights. Note the elevation at each antenna site.
The following section will show how to calculate the RSS level expected at the radio and to
determine the theoretical link margin at the sight.
Determine free-space path loss, using either table 3-1, the graph of figure 3-2, or the formula
following figure 3-2.
Table 3-1. Free-Space Path Loss at 2.4 GHz
Distance
(miles)
Path Loss
(dB)
Distance
(km)
Path Loss
(dB)
-104
-100
-110
-106
-114
-110
-116
-112
-118
-114
-120
-116
-121
-117
-122
-118
-123
-119
10
-124
10
-120
11
-125
15
-124
12
-126
20
-126
13
-126
25
-128
14
-127
30
-130
15
-128
35
-131
20
-130
40
-132
25
-132
45
-133
30
-134
50
-134
35
-135
55
-135
40
-136
60
-136
45
-137
70
-137
50
-138
80
-138
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AR24027 Operator’s Manual (rev E)
−95
−97
−99
−101
−103
−105
Path Loss (dB)
−107
−109
−111
−113
−115
−117
−119
−121
−123
−125
−127
−129
−131
Path Loss at 2.4 GHz
−133
−135
−137
−139
10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50
Path Length (miles)
−95
−97
−99
−101
−103
−105
Path Loss (dB)
−107
−109
−111
−113
−115
−117
−119
−121
−123
−125
−127
−129
−131
Path Loss at 2.4 GHz
−133
−135
−137
−139
10
15
20
25
30
35
40
45
50
55
60
Path Length (km)
Figure 3-2. Free-Space Path Loss at 2.4 GHz
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65
70
75
80
AR24027 Operator’s Manual (rev A)
−L = C + 20log(D) + 20 log(F)
Where:
(for US units)
-L
(or for metric units)

-L
loss in dB
6.6 for US units
path length in miles
2400 (frequency in MHz)
loss in dB
32.5 for metric units
path length in km
2400 (frequency in MHz)
For example, for a distance of 10 miles
−L = 36.6 + 20(1) + 20(3.38)
−L = −124 dB
Calculate effective radiated power (ERP) at the transmit antenna. Since the AR24027 is housed in an
outdoor enclosure, there is usually no transmission line loss as the antenna is generally connected
directly to the radio connector. However, if an additional cable is used between the radio and the
antenna cable, the cable loss (attenuation) must be included in order to calculate the correct RSS
level.
WR 2411 output power
+ 23 dBm
Cable attenuation
- 2 dB
Transmit antenna gain
+ 17 dB
Effective Output Power
+ 38 dBm
NOTE: Table 3.2 lists attenuation values for various cables.
Calculate the RSS level at the receive radio using the formula:
RSS = Pt - Lp + Gr
Where:
Pt
Lp
Gr
Output power from the transmit antenna
path loss
Gain of the receive antenna
For example, for the above system at a distance of 10 miles, with transmit output power of 38 dBm,
and a receive antenna gain of 24 dB, the equation would be:
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AR24027 Operator’s Manual (rev E)
RSS = 38 dBm - 124 dB + 24 dB
= -62 dBm
Calculate link margin by subtracting radio sensitivity from the calculated RSS level.
Calculated RSS level at receiver
-62 dBm
Sensitivity of 2411 at 11 Mbps
-81 dB
link margin
+19 dB
This figure, link margin, is the amount of signal received by the radio that is above the minimum
required for the radio to meet its performance characteristics. This value is important since it gives
the operator an indication of how much signal fade the system can tolerate. Signal fading may be
caused by multiple radio paths (reflections) atmospheric conditions such as rain, temperature
inversions, fog, etc., and may last anywhere from a few moments to several hours and cause as much
as 20 to 30 dB of signal strength loss. Although it is possible to operate a system with a link margin
as low as 5 dB, as general rule of thumb it is recommended that all systems have a link margin of
better than 20 dB.
3.3.4
Antenna Orientation
Antennas at each end of a communications link must be mounted similarly in terms of polarity, and
directional antennas must be carefully oriented towards each other. The choice of polarization –
horizontal vs. vertical – is in many cases arbitrary. However, interfering signals from such devices as
cellular phones and pagers are generally polarized vertically, and an excellent means of reducing their
effect is to mount system antennas for horizontal polarization. Of those antennas in section 3.2 for
AR24027 systems, the directional antennas can be mounted for horizontal or vertical polarization,
while the omnidirectional antennas use only vertical polarization. Horizontally polarized
omnidirectional antennas are available as a special purchase.
Orientation of directional antennas is critical because their sensitivity is greatly reduced outside a
fairly narrow angle. Performance of the system can be seriously degraded by mis-aligned directional
antennas. The AR24027 has a built in feature that allows the operator to use an audio to assist in
aligning the antenna. Refer to chapter 5 on the use of this built-in antenna alignment feature.
3.3.5
Cable Loss (Attenuation)
The AR24027 is housed in a watertight enclosure so that it may be mounted in very close proximity
to the antenna. Using short cables to connect the radio to the antenna reduces signal losses. Table 3.2
shows loss per 100 feet (30 meters) at 2.4 GHz for typical antenna cable types.
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AR24027 Operator’s Manual (rev A)
Table 3-2. Loss at 2.4 GHz for Standard Coaxial Cable Types
Cable Type
Loss per 100 ft. (30 m)
RG-8 A/U
14.4 dB
Belden 9913
8.0 dB
LMR 195
19 dB
LMR 400
6.7 dB
To determine total cable loss for your installation, perform the following calculation:
For US units, multiply length in feet by the loss figure and divide by 100.
For metric units, multiply length in meters by the loss figure and divide by 30.
For example, for a 75-foot length of Belden 9913, the loss is:
75 x 8.0
= 6.0 dB
100
3.3.6
Connector Loss
Loss is introduced with each pair of cable connectors. Attenuation losses of some standard cable
types are shown in the following table:
Connector type
Loss per connector
N-Type
0.25 dB
SMA-Type
0.25 dB
The loss of each pair of connectors on all cables must be included to determine the total signal loss
(attenuation) between the antenna and ODU.
3.3.7
Other Considerations – Antenna Grounding
WARNING
VERY IMPORTANT INFORMATION
As an elevated metal object with a wire connection below, an antenna is an excellent lightning
attractor, and an effective ground must be provided to deflect lightning strikes to ground. An
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AR24027 Operator’s Manual (rev E)
additional advantage of effective system grounding is the minimizing of electrical noise and
interference, which can significantly degrade system performance.
Grounding involves providing a good, very low resistance connection from the antenna and radio to
earth ground to provide a better path for lightning and electrical noise than that through the
equipment. The following points should be taken into account in setting up system grounding:
•
The antenna should be mounted on a mast or tower that is well grounded to earth.
•
All antenna lead connectors should be correctly installed to provide a good, solid connection to
the cable shield.
•
Threaded couplings mating antenna lead connectors should be clean and tight; bayonet type
connectors should not be used.
•
Weatherproof connectors must be used for outdoor connections to prevent corrosion, which will
interfere with grounding.
•
All power and antenna grounds should be made common at a single point such as an equipment
rack, cabinet enclosure chassis, or antenna tower. This single-point ground should have a solid
ground connection to earth.
•
If the unit is installed indoors, a surge arrestor or lightning protector should be installed at the
point where the antenna cable enters the building or cabinet. The lightning protector should be
properly grounded at the single-point chassis ground. Carefully follow the installation
instructions provided by the manufacturer of the protection device. Appropriate lightning
protectors are available from AFAR Communications Inc.
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AR24027 Operator’s Manual (rev A)
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AR24027 Operator’s Manual (rev E)
4 INSTALLATION AND SETUP
It is recommended that an initial check be performed on the bench before a field installation.
For this bench check out you need two AR24027 units. One of the radios will be configured to operate
as the “master” and the other as the “slave”. The first approach described below uses the “Ethernet
Console Program” to emulate the terminal across an Ethernet connection. The second approach uses
two terminals connected to the auxiliary port of the radios.
4.1 Bench Check Out (using radio Ethernet connection)
In order to use the Ethernet connection you need the “Ethernet Console Program” (Econsole)
provided in a floppy disk. See Appendix C for installation instructions for Econsole. Once Econsole
is installed, perform the following steps.
1. Connect the PC Ethernet port to the “To LAN” connector of the Power Inserter Unit of the master
radio. Use an Ethernet crossover cable if connecting the PC directly to the Power Inserter Unit,
or use a straight cable if connecting through a hub.
2. Connect each Power Inserter Unit to the respective AR24027 using a CAT 5 cable as defined in
section 2.
3. Connect each radio Antenna A port (N type connector) to an appropriate 2.4 GHz band antenna
using an RF coaxial cable.
4. Connect the two Power Inserter Units to a power outlet of the appropriate voltage.
5. At the PC open a DOS window and invoke the Econsole program by typing:
> econ
If only one radio is connected to the LAN, ECON will establish a connection with that radio. If
more than one radio are in the same LAN ECON provides a list of all radios found (see
Appendix C for more detailed instructions on the use of Econsole). Once a connection to the
radio is established, the radio outputs the prompt:
tdd-nnnnn #>
where nnnnn are the last five digits of the radio serial number (if the radio had previously been
configured the prompt will be the radio “name”).
6. Set the “slave” AR24027 to its factory default configuration by typing the commands:
> load factory
> save-configuration
7. Move the Ethernet cable from the slave power inserter to the power inserter connected to the
master radio. At the DOS window invoke once again the Econsole program. Configure the
second radio (defined as the “master”) by typing the commands:
> load factory
> tdd master
> save-configuration
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AR24027 Operator’s Manual (rev A)
8. Once a radio is configured as the master it will establish a RF communication with the second
radio. To verify this connection type:
> monitor-link clear=1
Verify that the status shows “MASTER IN SYNC”, the receive packet count is increasing and no
error counts are counting up.
9. Once the link is established, Econsole can be used to configure the local or the remote radio. In
order to switch the Econsole connection, logout of the current connection and re-invoke
Econsole:
> logout
> econ
Econsole will list the two radios and give a choice to connect to either. Section 5 describes the
command language used to further modify the radio’s operating parameters.
4.2 Bench Check Out (using radio auxiliary ports)
1. Connect each AR24027 Console Port to a terminal, or a PC running a terminal emulation
program. Configure the terminal settings as follows:
Baud rate: 9600
Word length: 8 bits
Parity: none
Stop bits: 1
2. Connect each Power Inserter Unit to the respective AR24027 using a CAT 5 cable as defined in
section 2.
3. Connect each radio Antenna A port (N type connector) to an appropriate 2.4 GHz band antenna
using an RF coaxial cable.
4. Connect the two Power Inserter Units to a power outlet of the appropriate voltage.
5. The radios output a banner identifying the software and hardware versions and serial number,
followed by the command prompt:
tdd-nnnnn #>
where nnnnn are the last five digits of the radio serial number.
6. Set the “slave” AR24027 to its factory default configuration by typing the command:
> load factory
> save-configuration
7. Configure the second radio (defined as the “master”) by typing the commands:
> load factory
> tdd master
> save-configuration
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AR24027 Operator’s Manual (rev E)
8. Once a radio is configured as the master it will establish a RF communication with the second
radio. To verify this connection type:
> monitor-link clear=1
Verify that the status shows “MASTER IN SYNC”, the receive packet count is increasing and no
error counts are counting up.
9. The terminal connected to each radio can be used to further modify the radio’s operating
parameters. Section 5 describes the command language used to perform those functions.
4.3 Field Installation
4.3.1
Configuration
The AR24027 units are shipped pre-configured with a factory default configuration. If the unit
configuration has been altered, you can always reload it with the command:
> load factory
The factory configuration sets the TDD synchronization mode to “auto”. If the units are paired with a
NetCrossing Gateway no changes need to be done to the configuration. If the radio is intended to
operate standalone, one of the radios need to be configured as the master, by issuing the command:
> tdd sync=master
This is all that is needed for two radios to establish a point-to-point link. Some other parameters that
you may want to modify, and the commands to modify them, are listed in the table below. Refer to 5
for a complete list and description of all parameters.
Parameter
Command
Comments
Transmit Power
rf-transmit-setup
The factory default is 18 dBm. You may want to adjust
it up or down to achieve a specific link margin. When
adjusting the power up, keep in mind the restrictions
described in section 4.3.5 and 4.3.6.
Channels
rf-transmit-setup
rf-receive-setup
The transmit and receive channels may be different from
each other. However the transmit channel of one unit
must match the receive channel of the other unit. See
section 4.3.4 for guidelines on how to select the
operating channels.
Speed
rf-transmit-setup
The factory default is 2.75 Mbps. The only reason to
reduce the speed is for very long range links, or under
interference, to take advantage of the higher sensitivity
at lower speeds.
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AR24027 Operator’s Manual (rev A)
4.3.2
Antenna Installation
NOTICE
The antennas for the AR24027 must be professionally installed on permanent structures for outdoor
operations. The installer is responsible for ensuring that the limits imposed by the applicable
regulatory agency (Federal Communications Commission, FCC, or CE) with regard to Maximum
Effective Isotropic Radiated Power (EIRP) and Maximum Permissible Exposure (MPE) are not
violated. These limits are described in the following sections.
The AR24027 is typically attached to a pole (with the clamp provided) with the antenna connectors
facing up. For optimum performance the radio must be mounted in close proximity to the antenna
with a cable run typically under 2 meters (6 feet). For the AR24027, AFAR Communications Inc.
provides the three antenna types listed below:
Antenna Type
Gain
AFAR Model Number
Omnidirectional
9 dBi
ATO-2409-000
Panel
18 dBi
ATD-2418-000
Dish Reflector
24 dBi
ATD-2424-000
Antennas at each end of the link must be mounted such that they have the same polarization, and
directional antennas must be carefully oriented towards each other. The choice of polarization
(horizontal vs. vertical) is, in many cases, arbitrary. However, many potentially interfering signals
are polarized vertically and an excellent means of reducing their effect is to mount the system
antennas for horizontal polarization.
Of those antennas listed above, the two directional antennas can be mounted for horizontal or vertical
polarization, while the omnidirectional antenna can only be mounted for vertical polarization.
Horizontally polarized omnidirectional antennas are available upon special request.
Proper grounding of the antenna is important for lightning protection as well as to prevent electrical
noise interference from other sources. The antenna should be mounted to a mast or tower that is well
grounded to Earth. Use threaded connectors to mate to the antenna lead connectors and check that all
connectors are clean and tight. Use weatherproof connectors in all outdoor couplings. We
recommend using “rubber mastic tape” like Scotch 2228 from 3M to further weatherproof outdoor
connections.
In locations where it is warranted, install lightning protectors at the N type connectors leading to the
antennas. You may also want to install a surge arrestor/lightning protection on the Ethernet cable
where it connects to the equipment rack. The lightning protectors should be properly grounded.
Carefully follow the installation instructions provided by the manufacturer of the lightning protection
device used.
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AR24027 Operator’s Manual (rev E)
4.3.3
Antenna Alignment
When mounting the high gain antenna (24 dBi), the proper antenna alignment is extremely important
since the beam-width of the antenna is very narrow. Once you perform a rough alignment and the
link is in operation, you can use the “monitor-link” and “antenna-alignment-aid” commands. Type:
> monitor-link
in order to update, every half second, the link statistics including the RSSI level. The antenna can
then be aligned so that the RSSI is maximized.
Since in many applications the antenna is on a tower where it is not practical to have a terminal
nearby, the AR24027 has an additional “antenna alignment aid” available at the outdoor unit. This
feature uses the three pin “Auxiliary port” connector to output an audio signal with a pitch
proportional to the receive signal strength. AFAR provides a special cable adapter that converts the
three-pin connector into a standard female audio jack. Use this cable to connect the three-pin
connector to a pair of standard headphones while aligning the antenna. At a terminal session issue the
command:
>aaa audio
(aaa is an abbreviation for “antenna-alignment-aid”)
and then align the antenna until you hear the highest audio pitch.
Once the antenna is aligned you may type the command:
>aaa off
to turn off the audio signal and revert the auxiliary port connector to console mode.
4.3.4
Spectrum Analysis and channel selection
Radio operation in unlicensed bands has the potential of suffering from interference from other
equipment operating in the same band. The use of directive antennas greatly reduces the potential for
interference. In addition, the AR24027 includes several features, described below, to identify and
overcome sources of interference.
The AR24027 can be commanded to perform a spectrum analysis of the ISM band and report the
results in either a graphical or tabular form. The command:
>spectrum-analysis input=a-antenna dwell=xx
instructs the radio to scan the entire band, dwelling on each channel for a programmable amount of
time, and record the highest signal level in that channel. This feature can be used to perform a site
survey and identify the best receive channel.
Note that even though the AR24027 channels are spaced 2 MHz apart, the receiver RF bandwidth is
approximately 5 MHz. Therefore the RSSI value reported for each channel represents the total
energy in a 5 MHz band centered around that channel. For this reason, a narrow band transmitter will
show up in the spectrum analysis report as a lobe with 5 MHz bandwidth. Conversely, you do not
need to find a quiet 5 MHz wide region in the spectrum analysis report to select a quiet channel, i.e.,
any single channel sample that shows a low “noise” level, is a good candidate to select a s a receive
channel.
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AR24027 Operator’s Manual (rev A)
Once a potential receive channel has been identified using the spectrum analysis tool, a “timing
analysis” may also be used to confirm that the selected channel is indeed clear. The command:
>time-analysis channel=xx input=a-antenna dwell=xx
instructs the radio to dwell on the specified channel for the specified amount of time. After taking
several samples the radio displays the signal level detected in that channel over time.
4.3.5
Output Power Limits (FCC)
The Federal Communications Commission (FCC) regulations limit the maximum Effective Isotropic
Radiated Power (EIRP) for spread spectrum systems operating in the 2.4 GHz band. Close to the band
edges, the output power must be limited to avoid spilling over into the FCC protected band from
2.4835 GHz to 2.500 GHz. The table below takes these considerations into account and shows the
maximum allowed output power for the various antennas
Maximum Output Power (dBm)
Channel
Frequency
(MHz)
Antenna Gain
9 dBi
18 dBi
2406.0
23
2408.0
23
2410.0
23
2412.0
23
2414.0
23
8 to 30
4.3.6
24 dBi
23
31
2462.0
23
32
2464.0
23
33
2466.0
23
34
2468.0
22
35
2470.0
21
36
2472.0
20
37
2474.0
10
Output Power Limits (CE)
The European Telecommunications Standards Institute (ETSI) regulations impose a limit of 20 dBm
as the maximum Effective Isotropic Radiated Power (EIRP) for direct sequence spread spectrum
systems operating in the 2.4 GHz band. The installer must reduce the output power of the AR24027
so that this limit is not exceeded. The antenna gain, cable and connector losses must be taken into
account when computing the maximum output power.
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AR24027 Operator’s Manual (rev E)
4.3.7
Maximum Permissible Exposure (MPE) Limitations
The installer must mount all transmit antennas so as to comply with the limits for human exposure to
radio frequency (RF) fields per paragraph 1.1307 of the FCC Regulations . The FCC requirements
incorporate limits for Maximum Permissible Exposure (MPE) in terms of electric field strength,
magnetic field strength, and power density.
Antenna installations must be engineered so that MPE is limited to 1 mW/cm2 , the more stringent
limit for "uncontrolled environments". The table below specifies the minimum distance that must be
maintained between the antenna and any areas where persons may have access, including rooftop
walkways, sidewalks, as well as through windows and other RF-transparent areas behind which
persons may be located.
Minimum Distance calculation to
avoid Antenna Radiation Hazard (exposure of 1 mW/cm2)
Antenna Gain (dBi):
18
24
Max. Output Power
23
23
23
MPE safe distance (cm)
11*
28*
63*
*NOTE: For fixed location transmitters, the minimum separation
distance is 2 m, even if calculations indicate a lower MPE distance.
4.4 Ethernet Bridging
The AR24027 operates as an Ethernet bridge. As a bridge, the AR24027 runs in “promiscuous mode”,
i.e., it examines all the Ethernet packets that are flowing in the local LAN. Since these Ethernet
packets contain a “source” and “destination” address, the radio quickly learns the addresses of all the
“local” stations connected to the LAN (all the “source” addresses of packets flowing in the LAN are
local).
Each AR24027 periodically transmits the information about the local Ethernet addresses to all other
radios. Therefore every AR24027 holds an Ethernet table that includes one entry for every Ethernet
address connected to any of the LANs (this table can be examined with the “show ethernet”
command).
With this information on hand, each AR24027 examines the destination address of every Ethernet
packet in the local LAN and makes one of the following decisions:
1. If the destination address is for a “local” station, discard the packet.
2. If the destination address is connected to a remote radio, queue that packet to be forwarded
through the appropriate RF port.
3. If the destination address is unknown, “flood” the packet into the network. The packet will show
up at every LAN connected to any radio in the network.
Each AR24027 has capacity to store 500 entries in its Ethernet table. Entries are erased after a certain
amount of time to allow for stations to be moved between LANs and not show up in two distinct
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AR24027 Operator’s Manual (rev A)
LANs. The user can control this time-out with the “ethernet” command. If the table ever gets full,
entries that have been least used are erased to make room for new entries.
Bridging has two major advantages over routing:
1. There is absolutely no configuration required. The AR24027 learns about all stations
automatically and routes the packets appropriately.
2.
All layer 3 protocols (IP, IPX or others) can be bridged.
4.5 Upgrading the Firmware.
4.5.1
Description
The operational firmware for the AR24027 is stored in Flash PROM and can be easily updated. The
Flash PROM can hold multiple versions of the firmware simultaneously. The table below lists some
of the “File Utility” commands used to download and manage the various files stored in Flash
PROM. A more detailed explanation for each command can be found in section 5.
File Utility command summary
Command
Description
directory
Lists all files stored in Flash PROM
delete-file filename
deletes the specified file from the directory
download-file path/filename
downloads the specified file from the PC path/filename
into the Flash PROM
set-default-program filename
Sets the indicated filename as the default program to run
after power up
run-file filename
loads the indicated program into RAM and executes it.
New firmware versions are made available from time to time at the following AFAR
Communications Inc. website:
http://www.afar-incs.com/software/ar24027.shtml
The firmware files are named:
tddNN_NN.bz (binary zipped file for downloads through the Ethernet port)
tddNN_NN.dwn (ascii file for download through the serial port, or via Telnet)
where NN_NN is the firmware version number. The website contains instructions for transferring the
files into your PC.
A new file can be downloaded into the radios in one of three ways: (1) Using the “econ” program
running in a PC connected to the same physical LAN as one of the radios. This is the fastest method
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AR24027 Operator’s Manual (rev E)
and allows you to download to both radios in the link from the same PC. (2) Using a Telnet session
from anywhere on the Internet. This requires the radio to have been pre-configured with an IP
address. (3) Using a terminal emulator program (e.g. HyperTerminal) running on a PC connected
through the serial port to the radio RS-232 auxiliary port. This method only allows you to download
to that specific radio.
The next three sessions explain in detail how to download a new file using each method.
4.5.2
Installing new firmware through the Ethernet port
This procedure assumes that the new firmware needs to be installed in both radios of a working link.
The upgrade is performed from a single PC connected via Ethernet to any one of the. Note that new
firmware does not need to be compatible with the firmware currently running. You can still
download incompatible firmware and restart the link from a single location.
1. If you have not done so, install the utility program “econ” in the PC. This utility program is
distributed with the radios and can also be downloaded from the website. Please refer to
appendix C for instructions on how to install this utility.
2. Make sure the file with the new firmware (file tddNN_NN.bz) is available in the PC.
3. Start the econsole utility by typing “econ” from a DOS window. Verify that the econ version is
2.00 or greater (if not download the latest version from the website). Econ will send a
“discovery” message and display all the radios that can be seen. Verify that all radios in the
network are listed. Then select one of the radios to log-on to that particular radio.
4. Issue the command:
>directory
to view a list of files stored in Flash PROM as well as the available free space. Verify that the
free space in flash PROM is larger than the size of the tddNN_NN.bz file in the PC. If there is
not enough space in Flash PROM delete one of the program files to make up space (use command
>delete filename).
5. If the radio configuration has been password protected, you must first unlock the protection with
the command:
>unlock enable-configuration=password
(when the configuration is unlocked, the radio prompt ends with the characters ‘#>. In locked
mode the prompt does not include the ‘#’ character).
6. Issue the command:
>download path/tddNN_NN.bz
where path/ is the directory in the PC where the tddNN_NN.bin file is stored. The path/
extension is not required if the file is in the same directory as the ECON program. As the
download proceeds econ displays a line showing the current percentage complete.
7. Once the download is complete, issue the command:
>set-default-program tddNN_NN
in order to make the new file the default program to run after a reset.
8. Issue the command:
>single-node-reboot-timeout 60
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AR24027 Operator’s Manual (rev A)
in order to speed up the network recovery after rebooting the master radio below (this step is not
necessary if the new firmware is known to be compatible with the old one but it does not hurt in
either case).
9. Depress the “F4” key to log-off the session with the current radio. “Econ” displays the list of all
radios from the initial discovery phase. Select the next radio and repeat steps 4 through 8.
10. Once all radios in the network have the new program, log onto the master radio (using econsole)
and issue the command:
>reboot
to cause the master radio to restart using the new firmware.
11. If the new firmware is compatible with the old one, the link will be reestablished in a short time
(with the master running the new version and the slave running the old version).
If the new firmware is incompatible with the old one, the link will not be reestablsihed. In this
case, after 60 seconds, the slave radio will reboot. It will then execute the new firmware and be
able to reestablish the link with the master.
12. Wait at least ten seconds from the moment you entered the reboot command, then press .
Econsole automatically attempts to reconnect to the master radio. Once a new session with that
radio is reopened issue the command:
> version
and check that the master radio is indeed executing the new version. Then issue the command:
>monitor-link
to verify that the link is reestablished.
13. Depress the “F4” key to log-off the session with the master radio. “Econ” displays the list of all
radios from the initial discovery phase. Select a different radio and issue the command:
>version
and check if that radio is running the new or old version. If the radio is already running the new
version repeat this step with the next radio. Otherwise perform the next step.
14. If the radio is running the old version issue the command:
>reboot
Wait at least ten seconds for the radio to perform its start up code and re-establish the link. Then
press . Econsole automatically attempts to reconnect to the same radio again. Once a new
session with that radio is reopened issue the command:
> version
and check that the radio is indeed executing the new version.
15. Repeat the previous two steps until all the radios are running the new firmware.
Note that the file downloads are executed with the links in full operation. The only downtime in the
network occurs when the radios are rebooting. The radio configuration is kept intact when a new
version is started. The downtime for the radio being restarted, is typically less than twenty seconds.
When upgrading to an incompatible version, the downtime will be less than one minute.
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4.5.3
Installing new firmware using Telnet
Telnet is a protocol that allows you to conduct a remote radio command session from a local host.
The radio must have been pre-configured with an IP address and be reachable, over the network, from
the local host. Refer to section 6 for details on how to configure a radio IP address and initiate a
Telnet session. The Telnet terminal emulation must have the capability of sending an ASCII file to
the remote machine. The following description assumes you are using Hyperterminal as the local
Telnet terminal emulation.
1. Verify that the new software is available in the local machine. The download software for
upgrade via Telnet must have a “.dwn” extension, e.g., tdd01_05.dwn.
2. Initiate a Telnet session with the radio as described in section 6.
3. If the radio configuration has been password protected, you must first unlock the protection with
the command:
>unlock enable-configuration=password
(when the configuration is unlocked, the radio prompt ends with the characters ‘#>. In locked
mode the prompt does not include the ‘#’ character).
4. Issue the command:
>directory
to view a list of files stored in Flash PROM as well as the available free space. Verify that there
is enough free space in flash PROM for the new file. The space required will be the size of the
tddNN_NN.dwn file divided by 2.5. If there is not enough space in Flash PROM delete one of
the program files to make up space (use command >delete filename).
5. Start the download process by typing:
>download-file destination=tddNN_NN method=inline
where NN_NN file is new version of software being installed.
6. The radio will return with the following:
“Send the file ... if incomplete, end with a line with just a period”
When you get this prompt, go to “Transfer-Send Text file…” in Hyperterminal and select the file
to be installed. The file must have a “.dwn” extension.
7. After the file is successfully installed issue the command:
>directory
to insure that the file has been loaded into memory.
8. Issue the command:
>set-default-program filename=tddNN_NN
where NN_NN file is new version of software being installed.
9. Issue the command:
>reboot
to restart the radio with the new software. Close the Telnet session, wait a few seconds and open
a new session with the same radio.
10. Issue the command:
>version
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AR24027 Operator’s Manual (rev A)
to insure the radio is running the latest version.
4.5.4
Installing new firmware using the RS-232 serial port
On occasion, it may be necessary to install new firmware using the RS-232 port. This is generally a
less desirable method as the download time is much longer and you can only update the radio that is
directly connected to the PC, i.e., remote updates are not possible.
The serial upgrade uses a PC with a terminal emulator. Any emulator can be used, however, it must
have the facility to download a text file on demand. In the example below, the emulator used is
Windows Hyperterminal.
1. Connect the AR24027 Auxiliary Port (3 pin circular connector) to a terminal, or a PC running a
terminal emulation program. A special adapter cable is supplied by AFAR. Configure the
terminal settings as follows:
Baud rate: 9600
Word length: 8 bits
Parity: none
Stop bits: 1
2. Verify that the new software is available in the PC. The download software for the serial upgrade
must have a “.dwn” extension, e.g., tdd01_05.dwn.
3. To have the shortest download time possible, set the radio to use the highest RS-232 speed
allowable on the PC. In this example, a download speed of 57600 baud will be used. Set the
console speed of the radio to 57600 baud by issuing the command:
>console-speed-bps 57600
4. Change the baud rate of the PC to match the radio. Remember that with Hyperterminal, you must
disconnect the session and re-connect before the changes will take effect. Verify the PC
communicates with the radio again.
5. If the radio configuration has been password protected, you must first unlock the protection with
the command:
>unlock enable-configuration=password
(when the configuration is unlocked, the radio prompt ends with the characters ‘#>. In locked
mode the prompt does not include the ‘#’ character).
6. Issue the command:
>directory
to view a list of files stored in Flash PROM as well as the available free space. Verify that there
is enough free space in flash PROM for the new file. The space required will be the size of the
tddNN_NN.dwn file divided by 2.5. If there is not enough space in Flash PROM delete one of
the program files to make up space (use command >delete filename).
7. Start the download process by typing:
>download-file destination=tddNN_NN method=inline
where NN_NN file is new version of software being installed.
8. The radio will return with the following:
“Send the file ... if incomplete, end with a line with just a period”
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AR24027 Operator’s Manual (rev E)
When you get this prompt, go to “Transfer-Send Text file…” in Hyperterminal and select the file
to be installed. The file must have a “.dwn” extension.
9. After the file is successfully installed issue the command:
>directory
to insure that the file has been loaded into memory.
10. Issue the command:
>set-default-program filename=tddNN_NN
where NN_NN file is new version of software being installed.
11. Issue the command:
>reboot
to restart the radio with the new software. Remember to change the PC Hyperterminal settings
back to 9600 baud and disconnect/re-connect the session.
12. Issue the command:
>version
to insure the radio is running the latest version.
4.5.5
Feature upgrades
The AR24027 has the ability to turn ON or OFF optional features and capabilities. This is done via
the use of the “license” command. This command requires a “key” that is specific to a particular
radio serial number and capability. To obtain a feature key, you must supply the specific model
number, the serial number, and the feature desired. Please contact your local distributor for a list of
optional features available for your radio.
Refer to Section 5.10 under “license” for the specific use of the license command.
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5 COMMANDS
5.1 Configuration techniques
There are three ways to configure the radio. One uses the auxiliary port at the bottom of the unit and
consists of an asynchronous RS-232 link used for issuing configuration commands and monitoring
the local radio status and performance. This port is always set to operate with the following
parameters:
Baud rate: 9600
Word length: 8 bits
Parity: none
Stop bits: 1
This console port allows configuring and monitoring only the local radio, i.e. you can not monitor and
configure any of the remote radios reachable through RF.
A preferred configuration method uses the Ethernet connection to the radio to perform the
configuration. This approach has the advantage that any radio reachable across the Ethernet, or the
RF link, can be configured from a single PC. Additionally the Ethernet connection is more readily
available indoors than the console port.
In order to use the Ethernet connection to configure the radios the “Ethernet Console Program”
(Econsole) needs to be installed at a PC. This PC must be connected to the LAN where one or more
AR24027 is connected. From this PC it is then possible to configure not only the radios directly
connected to the LAN, but also all other radios reachable through one or more RF hops. Refer to
Appendix C for instructions on the installation of Econsole.
The third configuration method is using Telnet from a remote location. Telnet is explained in more
detail in section 6.
After power up the radio performs several diagnostic and calibration tests. At the end of these tests it
outputs the command prompt. The default prompt is:
tdd-nnnnn #>
where nnnnn are the last five digits of the radio serial number. If a node “name” has been assigned to
the node, the prompt will be that name.
The “help” command provides a list of all the commands available. To get more detailed help for a
specific command, type “help command-name”.
The radio keeps a history of several of the previously issued commands. Those commands can be
viewed by pressing the up-arrow and down-arrow keys on the keyboard. Any of those previously
issued commands can then be edited and reentered by pressing the  key.
5.2 Command syntax
The command interpreter in the AR24027 is designed to accommodate both a novice as well as an
expert operator. All commands and parameters have descriptive names so that they are easily
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AR24027 Operator’s Manual (rev A)
remembered and their meaning is clear. In order to be descriptive however, those commands are
sometimes long. As the operator becomes familiar with the command language, typing the complete
words could become cumbersome. The AR24027 command interpreter recognizes any abbreviations
to commands and parameter names, as long as they are unambiguous. If an ambiguous command is
entered, the radio will output all possible choices.
Commands have the following generic form:
command parameter=value parameter=value
Following is a brief list of syntax rules:
•
Words (for commands, parameters, or values) can be abbreviated to a point where they are
unambiguous.
•
Some commands or parameters consist of compound words separated by an hyphen. With
compound words, the hyphen is optional. Additionally each word in a compound word can be
abbreviated separately. For example, the following are all valid abbreviations for the command
“save-configuration”: “save”, “savec” s-c” “sc”.
•
The parameter and value lists are context sensitive, i.e., in order to solve ambiguities the
command interpreter only considers parameters valid for current command, or values valid for the
current parameter.
•
The arguments “parameter=value” must be entered with no blank spaces on either side of the ‘=’
sign. Those arguments (parameter/value pairs) can be listed in any order.
•
Even though parameters can be listed in any order, there is a “natural” order known by the
command interpreter. This allows the user to specify parameter values without having to type the
parameter names. For example the command
>spectrum-analysis input=a-antenna display=table
can be entered as (using abbreviation rules as well):
>spa a t
•
Using the preceding rule, for commands that have a single argument, the “parameter name” part
of the argument is always optional, i.e., you can enter:
>command value
For example the command:
>show-tables table=radio-nodes
can be shortened to any of the following:
>show-tables radio-nodes
>show radio
>show rn
>sh
•
Not all parameters associated with a command need to be specified. Depending on the command,
when a parameter is omitted it either assumes a default value or keeps the last value assigned to
that parameter.
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AR24027 Operator’s Manual (rev E)
The following sections describe the various commands grouped according to their functionality. A
summary list of all commands are contained in Appendices A and B.
5.3 Configuration Management Commands
A “radio configuration” consists of a set of programmable parameters that define the radio operation
with regard to a variety of operating modes. The radio holds four configurations at all times,
identified as “current”, “main”, “alternate”, and “factory”.
The “main” and “alternate” configurations are both stored in non-volatile memory. They can be
loaded into the “current” configuration with the “load” command. On power up the radio loads the
“main” configuration from non-volatile memory into the current configuration.
The “current” configuration is the set of parameters currently being used and can be modified by the
operator through several commands. This configuration is volatile. If the current configuration has
been modified it should be saved using the “save” command. Otherwise the modifications will be
lost if power is removed.
The “factory” configuration can not be modified by the operator and is used to return the radio to the
factory default condition. It is useful as a starting point to create a customized configuration.
The access to change the radio configuration can be password protected. This password is set by the
user with the “change-password” command. Once a password is set, issue the “lock” command to
prevent any unauthorized changes to the configuration. Once locked, the configuration can only be
modified by issuing the “unlock” command with the correct password.
When the configuration is unlocked, the radio prompt ends with the characters ‘#>’ to remind the user
that the configuration is unlocked. In locked mode the prompt does not include the ‘#’ character.
Once a password is set, the radio will automatically lock the configuration after 10 minutes without
any commands being issued.
The configuration management commands are listed below:
change-password
enable-configuration=”ASCII string”
This command allows the user to set or change a password used to “lock” and “unlock” access
to the commands that change the radio configuration. The AR24027 is shipped with no
password which allows access to all commands. Once a password is set and the configuration
is locked, the password is needed to unlock the access to those commands. After changing the
password you should also issue the “save-configuration” command to save the new password in
non-volatile memory.
Examples:
> change-password enable-configuration=bh7g8
WARNING
The AR24027 is shipped with no password. If the “change-password” command is issued make sure
you do not forget the password. Once locked, without a password, the radio must be returned to the
factory to be unlocked.
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AR24027 Operator’s Manual (rev A)
display-configuration
source= current or main or alternate or factory
Displays all the parameter values for the specified configuration. If the source is not specified
it defaults to “current”.
Examples:
> display-configuration source=current
> discon
load-configuration
source=main or alternate or factory
Loads the specified configuration into the current set of parameters controlling the radio
operation. If no source is specified it defaults to the “main” configuration.
Examples:
> load-configuration source=factory
> load
lock
This command locks the access to all the commands that can alter the radio configuration.
Once locked use the “unlock” command to regain access to those commands. Note that a
password must be set prior to the “lock” command being issued (the radios are shipped with no
password), otherwise the lock command has no effect. If a password is set, the radio
automatically “locks” the configuration at the end of 10 minutes with no command activity.
save-configuration
destination=main or alternate
Saves the current set of radio operating parameters into one of the two non-volatile
configurations. If the destination is not specified it defaults to main.
Examples:
> save-configuration destination=alternate
> save
unlock
enable-configuration=”ASCII string”
This command, with the correct password, unlocks the access to the commands that allow the
radio configuration to be altered.
Examples:
> unlock enable-configuration=bh7g8
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5.4 Major Configuration Parameters
These commands change several operating parameters of the radio that are part of the radio
“configuration”. When entering commands with multiple parameters, if a parameter is not
included, that parameter keeps its current value.
node
name=”ASCII string”
Gives the node a meaningful name for further reference. This name will be used as the
command prompt. It is also used to identify the node in a variety of commands and displays.
The name field can be up to 11 characters with no spaces. If spaces are desired, you may
include the whole name in quotation marks.
location=”ASCII string”
Optional parameter to define the location of the node. This field is displayed in the “Displayconfiguration” output and also reported through SNMPThis field is used for information only. .
The location string can be up to 25 characters with no spaces. If spaces are desired, you may
include the whole string in quotation marks.
contact=”ASCII string”
Optional parameter to define the contact for maintenance purposes. This field is displayed in
the “Display-configuration” output and also reported through SNMP. This field is used for
information only. The contact string can be up to 25 characters with no spaces. If spaces are
desired, you may include the whole string in quotation marks.
Examples:
>node net-id=2754 name=bank location=”wall street” contact=964-5848
single-node-reboot-timeout
timeout-sec=30..3600
After power up, a radio attempts to get a link up with a peer. If a radio fails to get a link up (or
drops an existing link), it will perform a complete reset after the timeout specified in this
command.
This feature is useful if a command is issued to a remote radio changing its parameters in such a
way that breaks the link to its peer. In that case the remote radio will drop the link, wait for the
“single-node-reboot-timeout” and then perform a reset. As a result, the radio reverts to the
saved configuration, allowing it to get reattached to its peer.
Examples:
> snrt 60
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AR24027 Operator’s Manual (rev A)
rf-receive-setup
channel=5..35
antenna=a, b
This command configures the channel, and antenna used in the RF reception.
Note that for the radio to establish a link to its peer, the channel selected by this command must
match the channel selected as the transmit channel of the remote radio.
Example:
> rfre ch=15
rf-transmit-setup
channel=5..35
speed-mbps= 1, 2, 5.5, 11
power-dbm=0..23
antenna=a, b
This command configures the channel, speed, transmit power and antenna used in the RF
transmissions.
Note that for the radio to establish a link to its peer, the channel selected by this command must
match the channel selected as the receive channel of the remote radio.
Example:
> rftr ch=15 sp=2 po=18
time-division-duplex
sync=master, auto
cycle-period-ms= 5..30
This command configures the “time-division-duplex” parameters. When the radios are
operated standalone (not paired with a NetCrossing Gateway), the sync mode for one radio
must be set to “master” and the other to “auto”. If the radios are paired with NetCrossing
Gateways both radios should have their sync mode set to “auto”.
A radio configured as master transmits a short packet repeatedly, with a period specified by the
“cycle-period” parameter. The peer radio (with configuration set to “auto”), upon listening to
this packet, synchronizes its replies to the master timing. Transmitting in opposite phases.
The cycle period only needs top be programmed at the master radio. Use shorter cycle periods
to reduce the latency in the link and larger values to increase the link capacity.
Example:
> tdd sync=master cp=10
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5.5 Bridge Management Commands
Bridge management commands set and display the specific operating characteristics relating to the
operation of the radios as a network.
ethernet
speed=auto or 10hdx or 10fdx or 100hdx or off
Sets the ethernet port speed to auto-negotiate, 10Mbps half-duplex (10hdx), 10 Mbps fullduplex (10fdx), 100 Mbps half-duplex (100hdx) or turns the ethernet port off.
In installations requiring very long outdoors CAT5 cable, operation at 100 Mbps may become
unreliable. For this reason the auto-negotiate setting allows only 10 Mbps half or full-duplex.
For operation at 100 Mbps you need to specify that speed explicitly.
When the ethernet port is turned “off” no traffic is accepted from the ethernet port, but the radio
continues to operate over RF normally. This is useful for a radio configured as a repeater, if the
operator wants to turn off the user but needs to keep the service for radios downstream. Note
that once the ethernet port is turned off, it can only be turned back on through an RF connection
or the RS-232 console port.
timeout-sec=5..1800
Sets the time the radio will retain, in its internal table, Ethernet addresses obtained from the
network.
multi-cast-timeout-sec=5..3600
Sets the time the radio will retain, in its internal table, Ethernet multi-cast addresses obtained
from the network.
Examples:
> ethernet speed=10fdx timeout=100
show-tables
table=ethernet-stations
fomat=counts or times
This command displays a variety of information about the overall link. The contents of the
different tables are described below.
ethernet-stations table
This table can be displayed in two formats, “counts” (default) and “times”.
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AR24027 Operator’s Manual (rev A)
>show ethernet
Ethernet Stations:
MAC address
ff-ff-ff-ff-ff-ff
00-d0-39-00-2d-cb
00-a0-cc-66-8e-a6
00-d0-39-00-2d-c3
IP address
Radio
-M
207.154.90.171 S
--Discard-from
to
136
54
--Forward-from
to
183
209
165
139575
172
>show ethernet times
Ethernet Stations:
MAC address
0 ff-ff-ff-ff-ff-ff
1 00-d0-39-00-2d-cb
2 00-a0-cc-66-8e-a6
3 00-d0-39-00-2d-c3
IP address
Radio MC Time added
29-Nov 16:17:08
-M
29-Nov 16:17:08
207.154.90.171 S
29-Nov 16:17:15
29-Nov 16:23:41
Idle
0.01
0.00
9.18
Both formats lists all the ethernet stations attached to any of the radios. The tables lists the
MAC (Ethernet) address of the station, and, if known, the IP address. The “Radio” column
shows the radio (Master or Slave) where that station is physically attached.
The first entry in the table tracks broadcast traffic while the second entry is always the address
of the radio itself.
The “counts” format shows the cumulative number of ethernet packets that have been seen with
that MAC addresses in the “source” (from) or the “destination” (to) fields. In bridge mode the
radios are in “promiscuous” mode and look at all the ethernet packets in the Local Area
Network. The radios “discard” the packets that are known to be local, but “forward” all other
packets to the remote radio. These are accounted separately in the report.
The “times” format indicates whether that entry is for a “multicast” (MC) address, shows the
time when the station was added to the table, and how long since that address has been seen.
When the “idle” time exceeds the time specified by the “ethernet” command, that entry is
deleted from the table.
5.6 Internet Protocol (IP) Management Commands
The IP Management commands configure the radio IP protocol parameters which allow the radio to
be monitored and configured through Telnet and SNMP. Refer to section 6 for a more detailed
explanation on those two applications.
ip-configuration
address=
netmask=
gateway=
This command configures the radio IP address, netmask and gateway. The IP configuration is
optional and the radios are shipped with these parameters left blank. Once the IP configuration
has been initialized, the radios will reply to “ping” packets. The IP configuration is also
required in order to use the “ping”, “snmp” and “telnet” features.
Since the two radios in a link are bridged together they are in the same “internet network”.
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Example:
> ipconfig add=207.154.90.81 netmask=255.255.255.0 gateway=207.154.90.2
ping
destination=
count=0..500
size-bytes=32..1400
This command causes the radio to “ping” the destination address and display the results. The
“ping” packet consists of an ICMP packet with a length specified by the “size-bytes”
parameter. The destination is any valid IP address. When the destination host receives the
packet it generates a reply of the same size. Upon receiving the reply the radio displays the
round trip delay. This process is repeated the number of times specified by the “count”
parameter (default to 4).
Example:
> ping 207.154.90.81 count=10 size=100
snmp
The radio runs an SNMP agent which allows up to four IP addresses to be specified as valid
SNMP managers. This command configures those IP addresses and the type of access allowed.
You can issue the command up to four times to specify each separate IP address manager. The
radios are shipped with all entries blank. While no entries are specified, the unit accepts SNMP
“get” requests from any IP address with the “public” community. Once one or more entries are
specified, the radio only responds to requests from the specific IP addresses listed. This list of
authorized managers is also used for validating Telnet requests.
Refer to section 6 for an overview of Network Management using SNMP and Telnet.
manager=
Specifies one valid IP address where the SNMP manager or Telnet session will run.
community=
Any string of up to 9 characters. For SNMP requests the “community” field in the request
packet from this IP address must match this parameter. For a Telnet session the username
entered when initiating the session from this IP address must match this string. If this
parameter is not specified it defaults to “public”. Note that you must always enter the
“manager” IP address in the same command line that sets the “community” value.
access=g or gs or gst or gt
SNMP access type authorized for this IP manager. Specify as any combination of three letters:
g (get), s (set) and t(trap). If this parameter is not specified it defaults to “get”. Note that you
must always enter the “manager” IP address in the same command line that sets the “access”
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value.
authentication-traps=0 or 1
Specifies whether an “authentication trap” should be generated if a SNMP request is received
that can not be honored (due to invalid IP address, community or access fields). When enabled,
all IP managers that have “trap” access will receive this trap.
delete=1..4
Allows deleting one entry in the SNMP table. The number 1..4 refer to the entry number as
listed in the “display configuration” report.
Example:
> snmp manager=207.154.90.81 com=support access=gst
5.7 Installation and Link Monitoring Commands
These commands are useful as installation aids and also for monitoring link statistics after the link is
established.
antenna-alignment-aid
output=audio or off
With the antenna alignment aid set to “audio” the radio outputs, through the auxiliary port, an
audio signal with a pitch proportional to the Receive Signal Strengh (RSS) level of packets
received from the specified node. AFAR provides a special cable adapter that converts the
three-pin auxiliary port connector into a standard female audio jack. Use this cable to connect
the auxiliary port to a pair of standard headphones while aligning the antenna.
When the command to turn the audio output ON is issued, the radio displays a line indicating
which antenna is being aligned. Additionally the radio plays one of two short tunes identifying
antenna A or B.
While the antenna alignment is set to “audio” the RS-232 console output is not available.
When the antenna alignment output is set to “off” the auxiliary port output reverts to RS-232
console.
The antenna alignment output setting (“audio” or “off”) can also be saved as part of the radio
configuration. This is useful to take a pre-configured radio to an installation site with no need
to turn the antenna alignment ON (through a terminal) after power up.
Example:
>aaa audio
>aaa off
monitor-flow
This command continuously displays the ethernet data rates between this radio and its peer.
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monitor-link
clear=0 or 1
This command continuously displays link statistics with its peer. The statistics include, for
each direction of the link, the channel, speed, transmit power, RSSI, link distance and
cumulative number of packets sent and lost.
The “clear=1” parameter clears the cumulative counts in the report.
Examples:
>monitor-link clear=1
spectrum-analysis
input=a-antenna or b-antenna
display=graph or table
dwell-time-ms=0..1000
This command performs a scan of all the channels in the band, dwelling on each channel for the
specified amount of time (defaults to 20 milliseconds). While on each channel it measures the
RSSI for that channel and stores its peak value. It then displays the data collected in a
graphical or table formats (defaults to “graph”).
During the test the RF input into the radio can be selected between one of the two antennas.
Note that even though the AR24027 channels are spaced 2 MHz apart, the receiver RF
bandwidth is approximately 5 MHz. Therefore the RSSI value reported for each channel
represents the total energy in an 5 MHz band centered around that channel. For this reason, a
narrow band transmitter will show up in the spectrum analysis report as a lobe with 5 MHz
bandwidth. Conversely, you do not need to find a quiet 5 MHz wide region in the spectrum
analysis report to select a quiet channel, i.e., any single channel sample that shows a low
“noise” level, is a good candidate to select as a receive channel.
Examples:
>spectrum-analysis input=b-antenna
>spa dwell=500
time-analysis
channel=0..50
input=a-antenna or b-antenna
display=graph or table
dwell-time-ms=1, 2, 5, 10, 20, 50, 100, 200, 500
This command measures the RSSI for a single channel over a period of time. Each “sample”
consists of the maximum RSSI measured during the dwell time specified (defaults to 20
milliseconds). After collecting 60 samples the RSSI values are displayed graphically or
numerically (defaults to “graph”).
In this test the RF input into the radio can be selected between one of the two antennas.
Example:
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AR24027 Operator’s Manual (rev A)
>time-analysis input=b-antenna
>tia in=a dis=t dwell=500
5.8 Event Logging Commands
The AR24027 keeps track of various significant events in an “event log”. This event log holds up to
500 events. The first 100 entries in the log are filled sequentially after power up and are not
overwritten. The remaining 400 entries consist of the last 400 events recorded. All events are timetagged with system time.
Events are classified in different categories from level 0 (catastrophic error) to 7 (information).
clear-log
region= all-events or reboot-reasons
This command clears the contents of the system event log from the specified “region”. After a
code upgrade it is recommended to clear the reboot reasons since the pointer in non-volatile
memory pointing to the reason message may no longer be valid.
display-log
region=end or beginning or all-events or reboot-reasons
length=1..500
id=0..200
min-level=0..7
max-level=0..7
This command outputs to the terminal the specified “region” of the event log. The “length”
parameter specifies the number of events to output (defaults to 10). The remaining parameters
provide filters to leave out specific events. If the “id” parameter is specified, only the event
identified by that id will be displayed. The “min-level” and “max-level” settings allow the user
to display only the events with the specified category range.
The “reboot-reasons” region of the event log consist of the last four events that that caused the
radio to reboot. These events are stored in non-volatile memory. The time tag in these events
is the time the radio was up since it was rebooted, not the time of day.
Examples:
>display-log region=all
>display-log region=all length=300 min-level=2 max-level=6
max-event
Sets the event severity level that should be saved or displayed. These two parameters are saved
as part of the configuration
save=0..7
Only events of the specified level or below will be saved in the event log.
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AR24027 Operator’s Manual (rev E)
print=0..7
Events of the specified level or below will be output to the terminal as they occur.
Examples:
>max-event print=6
5.9 File Utilities
The AR24027 maintains a file system that allows multiple programs to be stored in either non-volatile
flash PROM or volatile RAM. New programs can be downloaded into the AR24027 memory through
the auxiliary port, through the Ethernet port, or to remote radio across the RF link.
One of the programs in flash PROM is designated as the default program to run after reboot. On
power up that program is copied from PROM into RAM and the code runs out of RAM.
Both sections of memory (non-volatile flash PROM and volatile RAM) are segregated into two
“directories”. The non-volatile flash PROM is called “flash” signifying the flash PROM and the
volatile RAM is called “tmp” signifying the temporary status of the program. Use the “directory”
command to view the programs loaded and whether they are in non-volatile or volatile memory.
Any program can be invoked with the command “run” without making it the default file. This is
useful when upgrading the software over an RF link as a way to ensure that the new code is working
correctly before making it the default.
console-speed-bps
baud-rate-bps=9600 or 19200 or 38400 or 57600 or 115200
Sets the Auxiliary port of the radio to the specified baud rate. This setting is not saved in the
radio configuration, the auxiliary port always powers up set for 9600 baud.
This command is useful to speed up the download process over the auxiliary port. Before
issuing the download command, use this command to change the radio console speed to the
highest baud rate supported by the PC. Then change the terminal settings to match the radio
speed. Issue the download command described below and initiate the transfer at the terminal.
Examples:
>console-speed-bps baud-rate-bps=115200
copy-file
source=filename
destination=filename
Copies the input-file into the output-file. If the memory location is not defined (flash or tmp),
the command assumes the flash directory.
Examples:
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>copy-file tmp/tdd01_02 tdd01_02
delete-file
filename=filename
Deletes the specified file from RAM or Flash PROM. If the memory location is not defined
(flash or tmp), the command assumes the flash directory.
Examples:
>delete-file filename=tdd01_03
directory
format=short or full
Lists all the files currently stored in flash PROM and RAM, their size, the sectors occupied and
the MD5 checksum (full version). It also indicates which of the files is the default program.
Files stored in flash PROM have the flash/ prefix. Files stored in RAM have the tmp/ prefix.
Examples:
>directory full
download-file
source=path/filename
destination=filename
method=inline or binary
Downloads a program file from a PC to the AR24027.
To download a file through the Ethernet port or across RF links you need to be running the
Econsole program on a PC attached to a radio through the Ethernet port. In this case the
program file must be in binary format (with extension .bin). The path/ in the source parameter
is the PC directory where the file resides. The program file is transferred to the AR24027 and is
stored in the radio memory under the name specified by the destination parameter. If the
destination parameter is omitted, the file will be stored in Flash PROM with the same name as
the source. Note that the “.bin” extension is not needed in the command. The download
“method” to use must be “binary” (which is the default).
Example:
>download C:\load\tdd01_12
download the file tdd01_12.bin from the PC directory C:\load into the unit file
flash/tdd01_12
If the download is performed from a terminal connected to the Auxiliary port, the file is in
ASCII format and has the extension .dwn. The download method must be “inline”. The source
parameter is not needed since, after issuing the command, the user must initiate the transfer of
the file from the terminal.
Example:
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AR24027 Operator’s Manual (rev E)
>download destination=tdd01_12 method=inline
After issuing the command initiate the file transfer using the terminal facilities..
run
filename=filename
Executes the specified file. The file is first copied into RAM and then the program is executed
out of RAM. If the radio is rebooted or power cycled, the radio reverts back to the program
defined as the default boot program. If the memory location is not defined (flash or tmp), the
command assumes the flash directory.
Examples:
>run tdd01_04
set-default-program
filename=filename
Sets the specified file as the default program to be loaded upon reboot or power cycle. Since
the default program must reside in flash memory, the “flash/” prefix is assumed and is not
required for the command.
Examples:
>set-default-program tdd01_04
5.10 Miscellaneous commands
date
The AR24027 will set the internal radio date and time automatically by decoding Network Time
Protocol (NTP) packets in the Ethernet LAN. The “zone” parameter specified with the “date”
or “time” command will then be used to display the date/time in local time. The “zone” value
is saved as part of the radio configuration.
If NTP packets are not available, the user can initialize the radio date and time with either the
“date” or “time” commands. The parameters for both commands are identical, but the
parameter order is different. The date command can be entered as:
> date 16-may-2000 10:32:06
date=day-month-year
Sets the date used by the radio. The day / month / year parameter may be separated by any
valid separator (‘-‘ ‘/’ etc.)
time=hh:mm:ss
Sets the radio time in hours, minutes and seconds. Use colons to separate the three fields.
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zone=zone-code or offset
Sets the time zone to be used by the radio to translate the NTP time to local time. It can be
specified by an offset from GMT (-0800 or +0200 for example), or as a “zone-code”. The valid
“zone-codes” and the respective offsets are shown below:
Zone
Pacific Standard Time
Pacific Daylight Time
Mountain Standard Time
Mountain Daylight Time
Central Standard Time
Central Daylight Time
Eastern Standard Time
Eastern Daylight Time
Greenwich Mean Time
zone code
offset
PST
PDT
MST
MDT
CST
CDT
EST
EDT
GMT
-0800
-0700
-0700
-0600
-0600
-0500
-0500
-0400
0000
help [command-name]
If no command is specified, displays the complete list of commands. If a command is specified
it displays the valid parameter and corresponding values for that specific command.
Examples:
>help monitor-link
history
Displays the previous commands entered.
license
key=< ASCII string>
The “license” command is used to turn ON or OFF a set of optional features or capabilities. The
key is a 35-character string combination of ASCII letters, numbers, and hyphens. The key must
be input with the syntax as shown in the example below, including hyphens, for the radio to
accept it. The characters can be input as upper or lower case.
After entering the key you must reboot the radio for the feature, enabled by the key, to take
effect.
Each key is unique for a particular radio serial number and capability, i.e. a key generated to
turn ON a capability on one serial number will not work on another radio.
Example:
>license key=02EL1-ZGZ42-G0000-00C54-81WAJ-C9BEK
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logout
Closes the current Econsole session.
reboot
Resets the radio causing the software to perform a complete start up sequence. This is
equivalent to power cycling the radio off and on.
time
time=hh:mm:ss
date=day-month-year
zone=zone-code or offset
This command is identical to the “date” command explained above except for the order of the
parameters. It allows the time and date to be entered as:
> time 10:32:06 16-may-2000
version
Displays the radio model and software version.
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AR24027 Operator’s Manual (rev E)
6 NETWORK MANAGEMENT
The radios operate as part of a network environment with many devices. Whether operated by an
Internet Service Provider (ISP) or the Information Technology (IT) department of a business, there is
often a need to supervise and manage the network from a central Network Operations Center (NOC).
This chapter describes the features of the AR24027 that are useful for this purpose.
6.1 Telnet
6.1.1
General
Telnet, which stands for Telecommunications Network, is a protocol that allows an operator to
connect to a remote machine giving it commands interactively. Once a telnet session is in progress,
the local machine becomes transparent to the user, it simply simulates a terminal as if there was a
direct connection to the remote machine. Commands typed by the user are transmitted to the remote
machine and the responses from the remote machine are displayed in the telnet simulated terminal.
6.1.2
Starting a Telnet Session
In order to start a telnet session with a radio you first need to configure the radio with a unique valid
IP address. This is done with the ip-configuration command described in section 5.6. This initial
configuration must be done using either the RS-232 console port or the ECON program.
Once the radio has an IP address, you must start the telnet application at the local machine and
establish a connection with the IP address of the radio. If the local machine is a PC running
Windows, you can start Telnet through Hyperterminal as follows:
1. Start the Hyperterminal application (in a typical Windows installation Hyperterminal can be
found from the Start button under Programs/Accessories/Communications…)
2. From the File menu choose New Connection.
3. In the Name field enter any name you wish and press the OK button. This will open the
“Connect To” window.
4. In the last field, titled “Connect using:”, select TCP/IP (Winsock). The fields above will
change to Host Address: and Port Number:.
5. In the Host Address field, type the IP address of the radio, then press the OK button.
6. TCP will now attempt to connect to the specified device. If successful the radio will request a
login name with the prompt login:
7. Type public followed by the Enter key
The radio will now display its prompt command and you may type any commands as described in
section 5.
If after entering the public login name, the terminal displays the message “Login Failed”, this may be
due to the radio being configured to be managed from only some specific IP addresses. This is
explained in the following section.
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6.1.3
Telnet Security
The remote management capability through Telnet opens the possibility for an unauthorized user to
login to any radio accessible through the Internet. The radio configuration can be password protected
with the use of the lock and unlock commands. If further security is desired you can specify up to
four source IP addresses that are authorized to initiate Telnet sessions with the radio. When
configured in this way, the radio will reject Telnet requests from all IP addresses that are not in the
authorized list.
The authorized source IP addresses for Telnet are the same addresses that are authorized to perform
SNMP management. They are entered using the snmp command described in section 5.6 and can be
viewed with the display-configuration command. When this list is empty, you can initiate a Telnet
session from any IP address with the login name public. When this list is not empty, Telnet sessions
can only be initiated from the listed hosts. Additionally, for each host, the login name must match the
string listed for the community field.
If you wish to use this security feature you need know the IP address of the local machine. On a PC
running Windows, one way to find its IP address is to open a DOS window and issue the command:
>ipconfig
6.2 SNMP
6.2.1
Command Line Interface Versus SNMP
Configuration settings on the AR24027 are displayed and modified using a command line interface,
which can be accessed using either the RS-232 console port, the ECONSOLE program, or via a
TELNET session.
In a NOC environment, there is a need for an automated monitoring system to collect on an ongoing
basis information from devices in the network for three purposes:
1) to build an inventory of all the devices of the network
2) to keep track of all devices on the network and raise alarms when any device becomes
unreachable (device failed, link down, etc)
3) to maintain statistics on traffic levels in order to implement usage-based charging, or to determine
where congestion exists in the network, so that the network can be expanded to accommodate
growth
Command line interfaces are not very suitable for these purposes, and the AR24027 supports the
Simple Network Management Protocol (SNMP) to assist in these tasks. SNMP is a simple,
transaction-based (command/response) protocol, which allows a variety of third-party software
products to query network devices and collect data for these purposes.
For a generic introduction to the SNMP protocol, we recommend the book "The Simple Book - An
Introduction to Internet Management" by Marshall T Rose (P T R Prentice-Hall, 1994).
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6.2.2
What is SNMP?
The SNMP protocol is described in the following documents:
•
RFC1157 - Simple Network Management Protocol (SNMP) - ftp://ftp.isi.edu/in-notes/rfc1157.txt
•
RFC1155 - Structure and identification of management information for TCP/IP-based internets ftp://ftp.isi.edu/in-notes/rfc1155.txt
•
RFC1213 - Management Information Base for Network Management of TCP/IP-based internets:
MIB-II - ftp://ftp.isi.edu/in-notes/rfc1213.txt
SNMP is a specification for the interaction (protocol) between the SNMP agent embedded in a
network device, and the SNMP manager software running on another machine in the network.
The data provided by the SNMP agent in a network device is described by a document called the MIB
(Management Information Base). MIB-II describes the basic information provided by all devices,
and additional documents describe optional extensions for components that may not exist in most
devices.
Devices may also provide non-standard MIB groups. In order for a network management system to
make use of these extended features, the MIB description must be obtained from the device
manufacturer and loaded into the management station.
SNMP data travels in IP packets, using the UDP port 161 for the agent, so in order to use SNMP, the
device must have an IP address.
6.2.3
Security Considerations in SNMP
SNMP was designed before the Internet grew commercial, and the original design was not secure.
Later versions intended to provide security, but grew cumbersome and complex. As a result, most
devices provide secure operation in a non-standard way.
The original SNMP design as embedded in the protocol, assigns network devices to named
communities. Any transactions exchanged between the agent and the manager include the name of the
community to which they both belong. The agent has a list of which access rights (set, get, trap) it
will grant for each community of which it is a member.
In the AR24027, this has been re-interpreted: The radio has a list of up to 4 management stations from
which it will accept requests, and for each one - identified by its IP address - it is indicated what
access rights it is granted, and which community string it must use. Requests from all other sources
are ignored. Refer to the snmp command in section 5.6 for details on how to configure the radio for
management using SNMP..
If no management stations are listed, get-requests with the community public will be accepted and
responded to from any IP address.
6.2.4
Examples of Network Management Systems
Some of the most common network management systems are listed below. All of them provide many
similar features, including network status displays showing key devices on a map, where the devices
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AR24027 Operator’s Manual (rev A)
change color if they have alarms, and with provisions for activating a remote paging device if there is
a problem.
WhatsUp Gold (Ipswitch Inc)
http://www.ipswitch.com/
USD 800 (approx)
SNMPc (Castle Rock Computing, Inc)
http://www.castlerock.com/
USD 900 to USD 2700 (approx, depending on options)
OpenView (Hewlett-Packard)
http://www.openview.hp.com/
USD 3,000 to USD 10,000
The OpenView product line has been revamped; HP is now positioning it not as a turnkey
software product, but as a custom adapted application to be bought through a value-added
implementation partner.
Multi-Router Traffic Graphing
http://www.mrtg.org/
This is a free, open-source software, capacity planning tool.
6.2.5
AR24027 Management Information Base (MIB)
The AR24027 implements only the core MIB-II. A management station will see 3 interfaces in the
interfaces group:
1 - VINE bridge
2 - Ethernet
3 - Radio
The first of these represents the attachment of the SNMP agent to the bridged network. Only IP traffic
seen by the embedded host is counted.
The ethernet device (ifIndex=2) represents the traffic passing through the radio's ethernet port. This is
what should be tracked by MRTG.
The third device represents the wireless transceiver. If will appear as down if the radio does not have
a working link to a neighbor (a root node must have at least one child, all other nodes must have a
parent). This is useful for confirming the loss of a link. The traffic counts show all packets to and
from the radio, including handshaking between adjacent radios, as well as data being relayed from
this radio's children to its parent and vice versa
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APPENDIX A - Specifications
RF Specifications
RF Frequency Band
2.406 GHz to 2.474 GHz (center frequencies)
RF Signal Bandwidth (-20 dBc)
4.6 MHz
RF Channels
35 (12 non-overlapping)
Transmitter Output Power
0 to 23 dBm (programmable)
Modulation Type
direct sequence spread spectrum
RF Data Rates (one way)
250, 500, 1375, 2750 Kbps
Receiver Sensitivity (10-6 BER)
-92 dBm (@ 250 Kbps)
–90 dBm (@ 500 Kbps)
-88 dBm (@ 1375 Kbps)
-85 dBm (@ 2750 Kbps)
Data Interfaces
Auxiliary Port
RS-232
Ethernet Port
10/100 BaseT (auto-negotiate)
Power Requirements
Input Voltage (Outdoor Unit)
+8 to +28 Volts DC
Input Voltage (AC)
110 VAC or 220 VAC
Power Consumption
less than 5 Watts
Environment
Temperature
-40 to +70 Degrees C
Max. Humidity
90% non-condensing
Mechanical:
Dimensions
4.72" wide x 8.66” high x 2.20” deep (120mm W x 220 H x 56 D)
Weight
2.4 lbs. (1.1 Kg).
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APPENDIX B – Channel Frequency Assignment
Frequency
Frequency
Frequency
Channel
(GHz)
Channel
(GHz)
Channel
(GHz)
2.406
15
2.430
27
2.454
2.408
16
2.432
28
2.456
2.410
17
2.434
29
2.458
2.412
18
2.436
30
2.460
2.414
19
2.438
31
2.462
2.416
20
2.440
32
2.464
2.418
21
2.442
33
2.466
10
2.420
22
2.444
34
2.468
11
2.422
23
2.446
35
2.470
12
2.424
24
2.448
36
2.472
13
2.426
25
2.450
37
2.474
14
2.428
26
2.452
Number of
Non-Overlapping
Channels
Suggested Channel Allocation
Frequency Separation
(MHz)
12
3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36
6.0
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APPENDIX C – Ethernet Console Program
EConsole v2.01 for Windows
Short description
The ethernet console program was developed in order to accommodate the remote configuration of a
radio, i.e. the configuration in cases where the physical access to the radio is not feasible, or it is
cumbersome. The software consists of two parts: the client and the server. The client runs on the
administrator's PC, while the server runs on the radio.
The communication is done via a TCP-like protocol. There is an acknowledgment for every packet
that is sent, as well as a retransmission mechanism when a packet gets lost.
Each radio allows multiple sessions, i.e. more than one client can be connected concurrently to the
same server (radio). Nevertheless, for performance reasons, it is not recommended to have more
concurrent sessions than they are really needed, and definitely not more than the maximum number
which currently is 4.
System requirements
• Win95, Win98, Windows ME, WinNT, Win2000, WinXP
• NetBIOS installed
• WinPCap installed
Note: With regard to Windows NT platform, the code has been tested with versions 4.0, or newer. There is also
a Linux beta version
Installation for Windows
In order to install the WinPCap library, if not already installed, just click on the WinPCap.exe.
Support and updates for this library can be found at http://netgroup-serv.polito.it/winpcap/. It is
strongly suggested to uninstall older versions of the library and reboot the machine before installing
the new one. NetBIOS is a software component that comes by default with all Windows system, so
you don't have to install it. To start the Econsole, simply open a MS-DOS window and type econ. For
available command line arguments, please read the "input arguments" section.
Included files
•
•
•
•
win_readme.doc The file that you are reading
econ.exe The EConsole client
WinPCap The Windows installer for the WinPCap library
input_script.txt A sample input script file, that contains a list of radio commands.
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Input arguments
You can provide the following arguments in the command line, even though none of them is required.
Input file
There are two sources for the input commands: the keyboard, or a text file. The second option is
useful when you are running the same set of commands periodically, so you want to avoid retyping
them every time you want to execute them. If there is an input file in the command line, then the
keyboard will be deactivated and only the function keys will be available. If the specified file cannot
be found, the application will be terminated.
example:
C: > econ -i input.txt
Sample input file:
help
# this is a comment - note that the character # must appear as the fist character
time
date
# the following is a local command specifying a delay in seconds
. delay 10
time
. delay 1.5
version
logout
As you probably noticed from the above file, all the lines are interpreted as radio command, unless:
a) They start with the character ‘#’ which implies a comment
b) They start with the character ‘.’ which implies a local command. Currently there is only one local
command, namely the delay < time in secs>
Important note: All the input scripts should end with the logout command. Since all the commands are terminated with the
new line character, there must be one command per line and after the final logout command you must have an extra empty
line.
Output file
When you want to capture the output of a session into a text file, you can pass the filename as an
argument. If the file does not exist it will be created, otherwise it will be overwritten.
example:
>econ -o output.txt
Radio MAC address
If you are interested in a specific radio, you can pass its MAC address and let the client ignore any
response from other radios. That's very handy when you are always getting connected to the same
radio and you want to avoid the manual selection of a preferred one. Very useful also in case you are
using scripts for fully automated procedures.
example:
>econ -r 00:78:24:22:BA:4F
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AR24027 Operator’s Manual (rev E)
Radio Serial Number
The same functionality as above (see Radio MAC address) can be achieved by providing the radio
serial number, instead of the radio physical address. Note that you should not include the initial UC
characters of the serial number (i.e. type 11078 instead of UC11078)
example:
>econ -r 11787
Local Physical Address
Even though econsole identifies the PC local physical address automatically, there are some cases in
which the user wants to specify the local address on his/her own. These cases usually arise when there
are multiple NIC cards with the same names under WinNT operating system. In such case, the econ
might pick up the wrong MAC address, and therefore the user should supply manually the physical
address as a command line argument.
example:
>econ -m 00:78:24:22:BA:4F
Inverse Screen Colors
You can change the default settings (white texture on black background) by providing the -b option,
which will change the settings to black characters on white background.
example:
>econ -b
Change the console window size
Currently you can specify two values, either 25 or 50. These values indicate the number of lines of
the MS-DOS window.
example:
>econ -l 50
Help
Function keys, including F1, are activated after you get connected to a radio. If you want to get help
from the command line, you can use the -h argument.
example:
>econ -h
Syntax:
econ 
argument list = argument list | argument | {}
argument = -o outputfile | -i inputfile | -r MAC address
Examples
Let's say you want to read a list of commands from the text file called in.txt, and capture the output to
a text file called out.txt. You are also interested only in a specific radio with MAC address equal to
00:78:24:22:BA:4F. In that case, you will start the EConsole with the following arguments (the
arguments order is irrelevent):
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AR24027 Operator’s Manual (rev A)
>econ -i in.txt -o out.txt -r 00:78:24:22:BA:4F or
If you are reading from the keyboard, and you are simply interested in capturing the output of the
session, use the following syntax:
>econ -o out.txt
Since no input file was specified, it is assumed that the keyboard will be used for input, and ALL
radios will participate in the discovery process.
Function Keys
Currently there are 6 different function keys.
F1 Online help - gives a short description of the other function keys and the input arguments
F2 Active/deactivate diagnostic messages. Initially diagnostic messages are not shown, therefore
if you want to see them you should press F2. Diagnostic messages include warnings, and
retransmission info in order to get an idea of the connection's speed/integrity. Error messages
are always shown.
F3 Terminates the current session and closes the application.
F4 Close the session with the current radio and display the results of the initial discovery phase
to allow the user to connect to a new radio.
F5 Reverse/Restore screen settings. Initially the screen displays white letters on black
background, but you can reverse it to black letters on a white background.
F6 - Increases the console window buffer. This introduces a side bar which enables the user to
scroll up and down. Available in Windows NT Only.
Troubleshooting & Updates
Common problems
1. Failed to open adapter
This usually happens when you haven't installed properly the WinPCap library, or you have
and older version of it. Please visit http://netgroup-serv.polito.it/winpcap/ to get the latest
version. You should also make sure that your Ethernet adapters are working properly.
2. Cannot find radio(s) even though they are running properly
Make sure that:
• The ethernet cables are OK
• You are getting connected to the right network segment (i.e. try all ethernet adapters)
• You are using the right MAC address. The system tries to identify the adapter physical
address through some NetBIOS calls in the Win9X case, or some NDIS queries in the
WinNT/Win2000 case. If NetBIOS is not installed, the econ will probably use the wrong
local host MAC address. Also if there are more than one Ethernet adapter installed with
the same name, this might cause problem in the WinNT case.
Resolution: Use the command line argument to specify the correct physical local address.
You can see all the local physical address by executing the ipconfig -all command. Example:
>econ -m 00:78:24:22:BA:4F
3. Find a radio but not getting connected
Check if the maximum number of sessions has been reached. The maximum number of
sessions on the server side is limited to four, therefore you should NOT connect to the same
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AR24027 Operator’s Manual (rev E)
radio multiple times if not absolutely necessary. When the number of sessions reaches the
limit the radio will ignore any new discovery messages.
Another reason might be a unreliable RF link causing a high packet loss. Since during the
discovery phase there isn't any retransmission mechanism, it is quite possible that you
managed to "see" the radio, but you weren't able to connect to it, because the connection
request packet was lost. In such case, try to connect again.
4. High drop rate - screen freezes momentarily - connection times out
There are two possible causes.
1. The link between the client (PC) and the server (radio) is very weak. If the packet drop rate is
more than 20%, then the connection is problematic.
2. There are multiple sessions opened on the same server. With many concurrent sessions the
server response may be noticeably slower. Always close the session gracefully by executing
the logout radio command, and not by closing the MS-DOS console. If the logout command
is not issued the session at the server will remain open for an additional 15 minutes. Use the
list long command to find out the number of open sessions.
5. If I leave the client inactive for half an hour, and try to type a new command, I get an unable to
transfer packet message or I get a "session timeout - application will be closed" message.
An open session times out after 15 minutes of inactivity on the server side, and 30 minutes on
the client side.
Report a bug & Updates
Please visit htttp://www.afar-inc.com/ for more info.
Acknowledgments
The WinPCap library was obtained from “Politecnico di Torino” and the code is distributed in binary
form as part of the Econsole. The following copyright notice applies to that library.
/*
* Copyright (c) 1999, 2000
* Politecnico di Torino. All rights reserved.
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that: (1) source code distributions
* retain the above copyright notice and this paragraph in its entirety, (2)
* distributions including binary code include the above copyright notice and
* this paragraph in its entirety in the documentation or other materials
* provided with the distribution, and (3) all advertising materials mentioning
* features or use of this software display the following acknowledgement:
* ``This product includes software developed by the Politecnico
* di Torino, and its contributors.'' Neither the name of
* the University nor the names of its contributors may be used to endorse
* or promote products derived from this software without specific prior
* written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
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