ZyXEL Communications EMG2881-T20A Dual-Band Wireless AC1300 Gigabit Ethernet Gateway User Manual Part 2
ZyXEL Communications Corporation Dual-Band Wireless AC1300 Gigabit Ethernet Gateway Users Manual Part 2
Contents
- 1. Users Manual Part 1.pdf
- 2. Users Manual Part 2.pdf
Users Manual Part 2.pdf
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9.6 UPnP Screen
Use this screen to enable UPnP on your EMG2881-T20A.
Click Configuration > Applications > UPnP to display the screen shown next.
Figure 46 Configuration > Applications > UPnP
The following table describes the fields in this screen.
9.7 Technical Reference
The following section contains additional technical information about the EMG2881-T20A features
described in this chapter.
IEEE 802.1Q Tag
The IEEE 802.1Q standard defines an explicit VLAN tag in the MAC header to identify the VLAN
membership of a frame across bridges. A VLAN tag includes the 12-bit VLAN ID and 3-bit user priority.
The VLAN ID associates a frame with a specific VLAN and provides the information that devices need to
process the frame across the network.
IEEE 802.1p specifies the user priority field and defines up to eight separate traffic types. The following
table describes the traffic types defined in the IEEE 802.1d standard (which incorporates the 802.1p).
Table 37 Configuration > Applications > UPnP
LABEL DESCRIPTION
UPnP Select Enable to activate UPnP. Be aware that anyone could use a UPnP application to
open the web configurator's login screen without entering the EMG2881-T20A's IP address
(although you must still enter the password to access the web configurator).
Apply Click Apply to save the setting to the EMG2881-T20A.
Cancel Click Cancel to return to the previously saved settings.
Table 38 IEEE 802.1p Priority Level and Traffic Type
PRIORITY
LEVEL TRAFFIC TYPE
Level 7 Typically used for network control traffic such as router configuration messages.
Level 6 Typically used for voice traffic that is especially sensitive to jitter (jitter is the variations in delay).
Level 5 Typically used for video that consumes high bandwidth and is sensitive to jitter.
Level 4 Typically used for controlled load, latency-sensitive traffic such as SNA (Systems Network
Architecture) transactions.
Level 3 Typically used for “excellent effort” or better than best effort and would include important business
traffic that can tolerate some delay.
Level 2 This is for “spare bandwidth”.
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DiffServ
QoS is used to prioritize source-to-destination traffic flows. All packets in the flow are given the same
priority. You can use CoS (class of service) to give different priorities to different packet types.
DiffServ (Differentiated Services) is a class of service (CoS) model that marks packets so that they
receive specific per-hop treatment at DiffServ-compliant network devices along the route based on the
application types and traffic flow. Packets are marked with DiffServ Code Points (DSCPs) indicating the
level of service desired. This allows the intermediary DiffServ-compliant network devices to handle the
packets differently depending on the code points without the need to negotiate paths or remember
state information for every flow. In addition, applications do not have to request a particular service or
give advanced notice of where the traffic is going.
DSCP and Per-Hop Behavior
DiffServ defines a new Differentiated Services (DS) field to replace the Type of Service (TOS) field in the IP
header. The DS field contains a 2-bit unused field and a 6-bit DSCP field which can define up to 64
service levels. The following figure illustrates the DS field.
DSCP is backward compatible with the three precedence bits in the ToS octet so that non-DiffServ
compliant, ToS-enabled network device will not conflict with the DSCP mapping.
The DSCP value determines the forwarding behavior, the PHB (Per-Hop Behavior), that each packet
gets across the DiffServ network. Based on the marking rule, different kinds of traffic can be marked for
different kinds of forwarding. Resources can then be allocated according to the DSCP values and the
configured policies.
IP Precedence
Similar to IEEE 802.1p prioritization at layer-2, you can use IP precedence to prioritize packets in a layer-3
network. IP precedence uses three bits of the eight-bit ToS (Type of Service) field in the IP header. There
are eight classes of services (ranging from zero to seven) in IP precedence. Zero is the lowest priority
level and seven is the highest.
Automatic Priority Queue Assignment
If you enable QoS on the EMG2881-T20A, the EMG2881-T20A can automatically base on the IEEE 802.1p
priority level, IP precedence and/or packet length to assign priority to traffic which does not match a
class.
Level 1 This is typically used for non-critical “background” traffic such as bulk transfers that are allowed but
that should not affect other applications and users.
Level 0 Typically used for best-effort traffic.
DSCP (6 bits) Unused (2 bits)
Table 38 IEEE 802.1p Priority Level and Traffic Type
PRIORITY
LEVEL TRAFFIC TYPE
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The following table shows you the internal layer-2 and layer-3 QoS mapping on the EMG2881-T20A. On
the EMG2881-T20A, traffic assigned to higher priority queues gets through faster while traffic in lower
index queues is dropped if the network is congested.
Token Bucket
The token bucket algorithm uses tokens in a bucket to control when traffic can be transmitted. The
bucket stores tokens, each of which represents one byte. The algorithm allows bursts of up to b bytes
which is also the bucket size, so the bucket can hold up to b tokens. Tokens are generated and added
into the bucket at a constant rate. The following shows how tokens work with packets:
• A packet can be transmitted if the number of tokens in the bucket is equal to or greater than the size
of the packet (in bytes).
• After a packet is transmitted, a number of tokens corresponding to the packet size is removed from
the bucket.
Table 39 Internal Layer2 and Layer3 QoS Mapping
PRIORITY
QUEUE
LAYER 2 LAYER 3
IEEE 802.1P USER
PRIORITY
(ETHERNET
PRIORITY)
TOS (IP
PRECEDENCE) DSCP IP PACKET LENGTH
(BYTE)
0 1 0 000000
12
2 0 0 000000 >1100
3 3 1 001110
001100
001010
001000
250~1100
4 4 2 010110
010100
010010
010000
5 5 3 011110
011100
011010
011000
<250
6 6 4 100110
100100
100010
100000
5 101110
101000
7 7 6 110000
111000
7
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• If there are no tokens in the bucket, the EMG2881-T20A stops transmitting until enough tokens are
generated.
• If not enough tokens are available, the EMG2881-T20A treats the packet in either one of the following
ways:
In traffic shaping:
• Holds it in the queue until enough tokens are available in the bucket.
In traffic policing:
•Drops it.
• Transmits it but adds a DSCP mark. The EMG2881-T20A may drop these marked packets if the
network is overloaded.
Configure the bucket size to be equal to or less than the amount of the bandwidth that the interface
can support. It does not help if you set it to a bucket size over the interface’s capability. The smaller the
bucket size, the lower the data transmission rate and that may cause outgoing packets to be dropped.
A larger transmission rate requires a big bucket size. For example, use a bucket size of 10 kbytes to get
the transmission rate up to 10 Mbps.
Single Rate Three Color Marker
The Single Rate Three Color Marker (srTCM, defined in RFC 2697) is a type of traffic policing that identifies
packets by comparing them to one user-defined rate, the Committed Information Rate (CIR), and two
burst sizes: the Committed Burst Size (CBS) and Excess Burst Size (EBS).
The srTCM evaluates incoming packets and marks them with one of three colors which refer to packet
loss priority levels. High packet loss priority level is referred to as red, medium is referred to as yellow and
low is referred to as green.
The srTCM is based on the token bucket filter and has two token buckets (CBS and EBS). Tokens are
generated and added into the bucket at a constant rate, called Committed Information Rate (CIR).
When the first bucket (CBS) is full, new tokens overflow into the second bucket (EBS).
All packets are evaluated against the CBS. If a packet does not exceed the CBS it is marked green.
Otherwise it is evaluated against the EBS. If it is below the EBS then it is marked yellow. If it exceeds the
EBS then it is marked red.
The following shows how tokens work with incoming packets in srTCM:
• A packet arrives. The packet is marked green and can be transmitted if the number of tokens in the
CBS bucket is equal to or greater than the size of the packet (in bytes).
• After a packet is transmitted, a number of tokens corresponding to the packet size is removed from
the CBS bucket.
• If there are not enough tokens in the CBS bucket, the EMG2881-T20A checks the EBS bucket. The
packet is marked yellow if there are sufficient tokens in the EBS bucket. Otherwise, the packet is
marked red. No tokens are removed if the packet is dropped.
Two Rate Three Color Marker
The Two Rate Three Color Marker (trTCM, defined in RFC 2698) is a type of traffic policing that identifies
packets by comparing them to two user-defined rates: the Committed Information Rate (CIR) and the
Peak Information Rate (PIR). The CIR specifies the average rate at which packets are admitted to the
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network. The PIR is greater than or equal to the CIR. CIR and PIR values are based on the guaranteed
and maximum bandwidth respectively as negotiated between a service provider and client.
The trTCM evaluates incoming packets and marks them with one of three colors which refer to packet
loss priority levels. High packet loss priority level is referred to as red, medium is referred to as yellow and
low is referred to as green.
The trTCM is based on the token bucket filter and has two token buckets (Committed Burst Size (CBS)
and Peak Burst Size (PBS)). Tokens are generated and added into the two buckets at the CIR and PIR
respectively.
All packets are evaluated against the PIR. If a packet exceeds the PIR it is marked red. Otherwise it is
evaluated against the CIR. If it exceeds the CIR then it is marked yellow. Finally, if it is below the CIR then
it is marked green.
The following shows how tokens work with incoming packets in trTCM:
• A packet arrives. If the number of tokens in the PBS bucket is less than the size of the packet (in bytes),
the packet is marked red and may be dropped regardless of the CBS bucket. No tokens are removed
if the packet is dropped.
• If the PBS bucket has enough tokens, the EMG2881-T20A checks the CBS bucket. The packet is
marked green and can be transmitted if the number of tokens in the CBS bucket is equal to or greater
than the size of the packet (in bytes). Otherwise, the packet is marked yellow.
9.7.1 Using UPnP in Windows XP Example
This section shows you how to use the UPnP feature in Windows XP. You must already have UPnP installed
in Windows XP and UPnP activated on the EMG2881-T20A.
Make sure the computer is connected to a LAN port of the EMG2881-T20A. Turn on your computer and
the EMG2881-T20A.
9.7.1.1 Auto-discover Your UPnP-enabled Network Device
1Click start and Control Panel. Double-click Network Connections. An icon displays under Internet
Gateway.
2Right-click the icon and select Properties.
Figure 47 Network Connections
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3In the Internet Connection Properties window, click Settings to see the port mappings there were
automatically created.
Figure 48 Internet Connection Properties
4You may edit or delete the port mappings or click Add to manually add port mappings.
Figure 49 Internet Connection Properties: Advanced Settings
Figure 50 Internet Connection Properties: Advanced Settings: Add
Note: When the UPnP-enabled device is disconnected from your computer, all port
mappings will be deleted automatically.
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5Select Show icon in notification area when connected option and click OK. An icon displays in the
system tray.
Figure 51 System Tray Icon
6Double-click on the icon to display your current Internet connection status.
Figure 52 Internet Connection Status
9.7.2 Web Configurator Easy Access
With UPnP, you can access the web-based configurator on the EMG2881-T20A without finding out the IP
address of the EMG2881-T20A first. This comes helpful if you do not know the IP address of the EMG2881-
T20A.
Follow the steps below to access the web configurator.
1Click Start and then Control Panel.
2Double-click Network Connections.
3Select My Network Places under Other Places.
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Figure 53 Network Connections
4An icon with the description for each UPnP-enabled device displays under Local Network.
5Right-click on the icon for your EMG2881-T20A and select Invoke. The web configurator login screen
displays.
Figure 54 Network Connections: My Network Places
6Right-click on the icon for your EMG2881-T20A and select Properties. A properties window displays with
basic information about the EMG2881-T20A.
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Figure 55 Network Connections: My Network Places: Properties: Example
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CHAPTER 10
Security
10.1 Overview
Use these screens to enable and configure the firewall that protects your EMG2881-T20A and your LAN
from unwanted or malicious traffic.
Enable the firewall to protect your LAN computers from attacks by hackers on the Internet and control
access between the LAN and WAN. By default the firewall:
• allows traffic that originates from your LAN computers to go to all of the networks.
• blocks traffic that originates on the other networks from going to the LAN.
The following figure illustrates the default firewall action. User A can initiate an IM (Instant Messaging)
session from the LAN to the WAN (1). Return traffic for this session is also allowed (2). However other traffic
initiated from the WAN is blocked (3 and 4).
Figure 56 Default Firewall Action
10.1.1 What You Can Do
• Use the IPv4 Firewall screen to enable or disable the EMG2881-T20A’s IPv4 firewall (Section 10.2 on
page 93).
• Use the IPv6 Firewall screen to enable or disable the EMG2881-T20A’s IPv6 firewall (Section 10.3 on
page 95).
10.1.2 What You Need To Know
The following terms and concepts may help as you read through this chapter.
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About the EMG2881-T20A Firewall
The EMG2881-T20A’s firewall feature physically separates the LAN and the WAN and acts as a secure
gateway for all data passing between the networks.
It is a stateful inspection firewall and is designed to protect against Denial of Service attacks when
activated (click the IPv4 Firewall or IPv6 Firewall tab under Security and then click the Enable Firewall
check box). The EMG2881-T20A's purpose is to allow a private Local Area Network (LAN) to be securely
connected to the Internet. The EMG2881-T20A can be used to prevent theft, destruction and
modification of data, as well as log events, which may be important to the security of your network.
The EMG2881-T20A is installed between the LAN and a broadband modem connecting to the Internet.
This allows it to act as a secure gateway for all data passing between the Internet and the LAN.
The EMG2881-T20A has one Ethernet WAN port and four Ethernet LAN ports, which are used to physically
separate the network into two areas.The WAN (Wide Area Network) port attaches to the broadband
(cable or DSL) modem to the Internet.
The LAN (Local Area Network) port attaches to a network of computers, which needs security from the
outside world. These computers will have access to Internet services such as e-mail, FTP and the World
Wide Web. However, "inbound access" is not allowed (by default) unless the remote host is authorized to
use a specific service.
Guidelines For Enhancing Security With Your Firewall
1Change the default password via Web Configurator.
2Think about access control before you connect to the network in any way, including attaching a
modem to the port.
3Limit who can access your router.
4Don't enable any local service (such as NTP) that you don't use. Any enabled service could present a
potential security risk. A determined hacker might be able to find creative ways to misuse the enabled
services to access the firewall or the network.
5For local services that are enabled, protect against misuse. Protect by configuring the services to
communicate only with specific peers, and protect by configuring rules to block packets for the services
at specific interfaces.
6Protect against IP spoofing by making sure the firewall is active.
7Keep the firewall in a secured (locked) room.
10.2 IPv4 Firewall Screen
Use this screen to enable or disable the EMG2881-T20A’s IPv4 firewall. Click Configuration > Security >
IPv4 Firewall to open the firewall setup screen.
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Figure 57 Configuration > Security > IPv4 Firewall
The following table describes the labels in this screen.
Table 40 Configuration > Security > IPv4 Firewall
LABEL DESCRIPTION
ICMP Internet Control Message Protocol is a message control and error-reporting protocol between
a host server and a gateway to the Internet. ICMP uses Internet Protocol (IP) datagrams, but
the messages are processed by the TCP/IP software and directly apparent to the application
user.
Respond to Ping
on
The EMG2881-T20A will not respond to any incoming Ping requests when Disable is selected.
Select LAN to reply to incoming LAN Ping requests. Select WAN to reply to incoming WAN Ping
requests. Otherwise select LAN&WAN to reply to all incoming LAN and WAN Ping requests.
Firewall Setup
Enable Firewall Select this check box to activate the firewall. The EMG2881-T20A performs access control and
protects against Denial of Service (DoS) attacks when the firewall is activated.
Enable Firewall Rule
Enable Firewall
Rule
Select this check box to activate the firewall rules that you define (see Add Firewall Rule
below).
Filter table type Select DROP to silently discard the packets which meet the firewall rules. The others are
accepted.
Select ACCEPT to allow the passage of the packets which meet the firewall rules. The others
are blocked.
Add Firewall Rule
Service Name Enter a name that identifies or describes the firewall rule.
MAC Address Enter the MAC address of the computer for which the firewall rule applies.
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10.3 IPv6 Firewall Screen
This chapter shows you how to enable and create IPv6 firewall rules to filter IPv6 traffic.
Dest IP Address Enter the IP address of the computer to which traffic for the application or service is entering.
The EMG2881-T20A applies the firewall rule to traffic initiating from this computer.
Source IP Address Enter the IP address of the computer that initializes traffic for the application or service.
The EMG2881-T20A applies the firewall rule to traffic initiating from this computer.
Protocol Select the protocol (TCP, UDP or ICMP) used to transport the packets for which you want to
apply the firewall rule.
Dest Port Range This is the port number/range of the destination that define the traffic type, for example TCP
port 80 defines web traffic.
Source Port Range This is the port number/range of the source that define the traffic type, for example TCP port
80 defines web traffic.
Add Rule Click Add Rule to save the firewall rule.
Firewall Rule
# This is your firewall rule number. The ordering of your rules is important as rules are applied in
turn.
Service Name This is a name that identifies or describes the firewall rule.
MAC address This is the MAC address of the computer for which the firewall rule applies.
Dest IP This is the IP address of the computer to which traffic for the application or service is entering.
Source IP This is the IP address of the computer from which traffic for the application or service is
initialized.
Protocol This is the protocol (TCP, UDP or ICMP) used to transport the packets for which you want to
apply the firewall rule.
Dest Port Range This is the port number/range of the destination that define the traffic type, for example TCP
port 80 defines web traffic.
Source Port Range This is the port number/range of the source that define the traffic type, for example TCP port
80 defines web traffic.
Delete Click to remove the firewall rule.
Apply Click Apply to save the settings.
Cancel Click Cancel to start configuring this screen again.
Table 40 Configuration > Security > IPv4 Firewall (continued)
LABEL DESCRIPTION
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Click Configuration > Security > IPv6 Firewall. The IPv6 Firewall screen appears as shown.
Figure 58 Configuration > Security > IPv6 Firewall
The following table describes the labels in this screen.
Table 41 Configuration > Security > IPv6 Firewall
LABEL DESCRIPTION
Enable Firewall Rule
Enable Firewall Rule Select this check box to activate the firewall rules that you define (see Add Firewall Rule
below).
Filter table type Select DROP to silently discard the packets which meet the firewall rules. The others are
accepted.
Select ACCEPT to allow the passage of the packets which meet the firewall rules. The others
are blocked.
Add Firewall Rule
Service Name Enter a name that identifies or describes the firewall rule.
MAC Address Enter the MAC address of the computer for which the firewall rule applies.
Dest IP Address Enter the IPv6 address of the computer to which traffic for the application or service is
entering.
The EMG2881-T20A applies the firewall rule to traffic destined for this computer.
Source IP Address Enter the IPv6 address of the computer that initializes traffic for the application or service.
The EMG2881-T20A applies the firewall rule to traffic initiating from this computer.
Protocol Select the protocol (TCP, UDP or ICMPv6) used to transport the packets for which you want
to apply the firewall rule.
Dest Port Range Enter the port number/range of the destination that defines the traffic type, for example
TCP port 80 defines web traffic.
Source Port Range Enter the port number/range of the source that defines the traffic type, for example TCP
port 80 defines web traffic.
Add Rule Click Add Rule to save the firewall rule.
Firewall Rule
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#This is your firewall rule number. The ordering of your rules is important as rules are applied in
turn.
ServiceName This is a name that identifies or describes the firewall rule.
MAC Address This is the MAC address of the computer for which the firewall rule applies.
Dest IP This is the IP address of the computer to which traffic for the application or service is
entering.
Source IP This is the IP address of the computer to which traffic for the application or service is
initialized.
Protocol This is the protocol (TCP, UDP or ICMPv6) used to transport the packets for which you want to
apply the firewall rule.
Dest Port Range This is the port number/range of the destination that defines the traffic type, for example
TCP port 80 defines web traffic.
Source Port Range This is the port number/range of the source that defines the traffic type, for example TCP
port 80 defines web traffic.
Delete Click to remove the firewall rule.
Apply Click Apply to save the settings.
Cancel Click Cancel to restore your previously saved settings.
Table 41 Configuration > Security > IPv6 Firewall (continued)
LABEL DESCRIPTION
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CHAPTER 11
Maintenance
11.1 Overview
This chapter provides information on the Maintenance screens.
11.2 What You Can Do
• Use the General screen to set the timeout period of the management session (Section 11.3 on page
98).
• Use the Password screen to change your EMG2881-T20A’s system password (Section 11.4 on page
99).
• Use the Time screen to change your EMG2881-T20A’s time and date (Section 11.5 on page 100).
• Use the Firmware Upgrade screen to upload firmware to your EMG2881-T20A (Section 11.6 on page
101).
• Use the Backup/Restore screen to view information related to factory defaults, backup configuration,
and restoring configuration (Section 11.8 on page 104).
• Use the Restart screen to reboot the EMG2881-T20A without turning the power off (Section 11.8 on
page 104).
• Use the Log screen to see the logs for the activity on the EMG2881-T20A (Section 11.9 on page 104).
• Use the ROMD screen to save and/or clean the configuration to/from the ROMD file which can store
customized default settings.
11.3 General Screen
Use this screen to set the management session timeout period. Click Maintenance > General. The
following screen displays.
Figure 59 Maintenance > General
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The following table describes the labels in this screen.
11.4 Password Screen
It is strongly recommended that you change your EMG2881-T20A's password.
If you forget your EMG2881-T20A's password (or IP address), you will need to reset the device. See
Section 11.8 on page 104 for details.
Click Maintenance > Password. The screen appears as shown.
Figure 60 Maintenance > Password
The following table describes the labels in this screen.
Table 42 Maintenance > General
LABEL DESCRIPTION
System Name System Name is a unique name to identify the EMG2881-T20A in an Ethernet network.
Domain Name Enter the domain name you want to give to the EMG2881-T20A.
Administrator
Inactivity Timer
Type how many minutes a management session can be left idle before the session times out. The
default is 5 minutes. After it times out you have to log in with your password again. Very long idle
timeouts may have security risks. A value of "0" means a management session never times out,
no matter how long it has been left idle (not recommended).
Apply Click Apply to save your changes back to the EMG2881-T20A.
Cancel Click Cancel to exit this screen without saving.
Table 43 Maintenance > Password
LABEL DESCRIPTION
User This field displays the name of the admin account.
Old Password Type the default password or the existing password you use to access the system in this
field.
New Password Type your new system password (up to 30 characters). Note that as you type a password,
the screen displays an asterisk (*) for each character you type.
Retype to Confirm Type the new password again in this field.
Apply Click Apply to save your changes back to the EMG2881-T20A.
Cancel Click Cancel to begin configuring this screen afresh.
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11.5 Time Screen
Use this screen to configure the EMG2881-T20A’s time based on your local time zone. To change your
EMG2881-T20A’s time and date, click Maintenance > Time. The screen appears as shown.
Figure 61 Maintenance > Time
The following table describes the labels in this screen.
Table 44 Maintenance > Time
LABEL DESCRIPTION
Current Time and Date
Current Time This field displays the time of your EMG2881-T20A.
Each time you reload this page, the EMG2881-T20A synchronizes the time with the time server.
Current Date This field displays the date of your EMG2881-T20A.
Each time you reload this page, the EMG2881-T20A synchronizes the date with the time server.
Time and Date Setup
Manual Select this radio button to enter the time and date manually. If you configure a new time and
date, Time Zone and Daylight Saving at the same time, the new time and date you entered has
priority and the Time Zone and Daylight Saving settings do not affect it.
New Time
(hh:mm:ss)
This field displays the last updated time from the time server or the last time configured manually.
When you select Manual, enter the new time in this field and then click Apply.
New Date
(yyyy/mm/dd)
This field displays the last updated date from the time server or the last date configured
manually.
When you select Manual, enter the new date in this field and then click Apply.
Get from Time
Server
Select this radio button to have the EMG2881-T20A get the time and date from the time server
you specified below.
User Defined
Time Server
Address
Enter the IP address or URL (up to 20 extended ASCII characters in length) of your time server.
Check with your ISP/network administrator if you are unsure of this information.
Time Zone Setup
Time Zone Choose the time zone of your location. This will set the time difference between your time zone
and Greenwich Mean Time (GMT).
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11.6 Firmware Upgrade Screen
Find firmware at www.zyxel.com in a file that (usually) uses the system model name with a “*.bin”
extension, e.g., “EMG2881-T20A.bin”. The upload process uses HTTP (Hypertext Transfer Protocol) and
may take up to two minutes. After a successful upload, the system will reboot.
Click Maintenance > Firmware Upgrade. Follow the instructions in this screen to upload firmware to your
EMG2881-T20A.
Figure 62 Maintenance > Firmware Upgrade
Daylight Savings Daylight saving is a period from late spring to early fall when many countries set their clocks
ahead of normal local time by one hour to give more daytime light in the evening.
Select this option if you use Daylight Saving Time.
Start Date Configure the day and time when Daylight Saving Time starts if you selected Daylight Savings.
The o’clock field uses the 24 hour format. Here are a couple of examples.
Daylight Saving Time starts in most parts of the United States on the first Sunday of April. Each
time zone in the United States starts using Daylight Saving Time at 2 A.M local time. So in the
United States you would select First, Sunday, April and type 2 in the o’clock field.
Daylight Saving Time starts in the European Union on the last Sunday of March. All of the time
zones in the European Union start using Daylight Saving Time at the same moment (1 A.m. GMT
or UTC). So in the European Union you would select Last, Sunday, March. The time you type in the
o’clock field depends on your time zone. In Germany for instance, you would type 2 because
Germany’s time zone is one hour ahead of GMT or UTC (GMT+1).
End Date Configure the day and time when Daylight Saving Time ends if you selected Daylight Savings.
The o’clock field uses the 24 hour format. Here are a couple of examples.
Daylight Saving Time ends in the United States on the last Sunday of October. Each time zone in
the United States stops using Daylight Saving Time at 2 A.M. local time. So in the United States
you would select Last, Sunday, October and type 2 in the o’clock field.
Daylight Saving Time ends in the European Union on the last Sunday of October. All of the time
zones in the European Union stop using Daylight Saving Time at the same moment (1 A.M. GMT
or UTC). So in the European Union you would select Last, Sunday, October. The time you type in
the o’clock field depends on your time zone. In Germany for instance, you would type 2
because Germany’s time zone is one hour ahead of GMT or UTC (GMT + 1).
Apply Click Apply to save your changes back to the EMG2881-T20A.
Cancel Click Cancel to exit this screen without saving.
Table 44 Maintenance > Time (continued)
LABEL DESCRIPTION
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The following table describes the labels in this screen.
Do not turn off the EMG2881-T20A while firmware upload is in progress!
After you see the Firmware Upload In Process screen, wait two minutes before logging into the
EMG2881-T20A again.
The EMG2881-T20A automatically restarts in this time causing a temporary network disconnect. In some
operating systems, you may see the following icon on your desktop.
Figure 63 Network Temporarily Disconnected
After two minutes, log in again and check your new firmware version in the Status screen.
If the upload was not successful, an error message appears.
11.7 Configuration Backup/Restore Screen
Backup configuration allows you to back up (save) the EMG2881-T20A’s current configuration to a file
on your computer. Once your EMG2881-T20A is configured and functioning properly, it is highly
recommended that you back up your configuration file before making configuration changes. The
backup configuration file will be useful in case you need to return to your previous settings.
Restore configuration allows you to upload a new or previously saved configuration file from your
computer to your EMG2881-T20A.
Click Maintenance > Backup/Restore. Information related to factory defaults, backup configuration,
and restoring configuration appears as shown next.
Table 45 Maintenance > Firmware Upgrade
LABEL DESCRIPTION
Firmware Upgrade
File Path Type in the location of the file you want to upload in this field or click Choose File to find it.
Choose File Click Choose File to find the .bin file you want to upload. Remember that you must decompress
compressed (.zip) files before you can upload them.
Upload Click Upload to begin the upload process. This process may take up to two minutes.
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Figure 64 Maintenance > Backup/Restore
The following table describes the labels in this screen.
Note: If you uploaded the default configuration file you may need to change the IP address
of your computer to be in the same subnet as that of the default EMG2881-T20A IP
address (192.168.1.1). See Appendix B on page 121 for details on how to set up your
computer’s IP address.
Table 46 Maintenance > Backup/Restore
LABEL DESCRIPTION
Backup Configuration
Backup Click Backup to save the EMG2881-T20A’s current configuration to your computer.
Restore Configuration
File Path Click Choose File to browse to the location of the configuration file in your computer.
Upload Click Upload to begin the upload process.
Note: Do not turn off the EMG2881-T20A while configuration file upload is in progress.
After you see a “configuration upload successful” screen, you must then wait one minute before
logging into the EMG2881-T20A again. The EMG2881-T20A automatically restarts in this time
causing a temporary network disconnect.
If you see an error screen, click Back to return to the Backup/Restore screen.
Reset Pressing the Reset button in this section clears all user-entered configuration information and
returns the EMG2881-T20A to its factory defaults.
You can also press the RESET button on the rear panel to reset the factory defaults of your
EMG2881-T20A. Refer to the chapter about introducing the Web Configurator for more
information on the RESET button.
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11.8 Restart Screen
System restart allows you to reboot the EMG2881-T20A without turning the power off.
Click Maintenance > Restart to open the following screen.
Figure 65 Maintenance > Restart
Click Restart to have the EMG2881-T20A reboot. This does not affect the EMG2881-T20A's configuration.
11.9 Log Screen
The Web Configurator allows you to look at all of the EMG2881-T20A’s logs in one location.
You can configure which logs to display in the Log screen. Select the logs you wish to display. Click
Apply to save your settings. Click Cancel to start the screen afresh.
Use this screen to see the logged messages for the EMG2881-T20A. The log wraps around and deletes
the old entries after it fills. Select what logs you want to see from the Display drop list. The log choices
depend on your settings above this screen. Click Refresh to renew the log screen. Click Clear Log to
delete all the logs.
Figure 66 Maintenance > Log
11.10 The ROMD Screen
Click Maintenance > ROMD to open the following screen.
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Figure 67 Maintenance > ROMD
Click Save to save the EMG2881-T20A’s current configuration to the ROM-D file. Click Clear to reset the
customized settings in the ROM-D file to factory defaults.
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CHAPTER 12
Troubleshooting
12.1 Overview
This chapter offers some suggestions to solve problems you might encounter. The potential problems are
divided into the following categories.
•Power, Hardware Connections, and LEDs
•EMG2881-T20A Access and Login
•Internet Access
•Resetting the EMG2881-T20A to Its Factory Defaults
•Wireless Connections
12.2 Power, Hardware Connections, and LEDs
The EMG2881-T20A does not turn on. None of the LEDs turn on.
1Make sure you are using the power adaptor or cord included with the EMG2881-T20A.
2Make sure the power adaptor or cord is connected to the EMG2881-T20A and plugged in to an
appropriate power source. Make sure the power source is turned on.
3Disconnect and re-connect the power adaptor or cord to the EMG2881-T20A.
4If the problem continues, contact the vendor.
One of the LEDs does not behave as expected.
1Make sure you understand the normal behavior of the LED. See Section 1.5 on page 12.
2Check the hardware connections. See the Quick Start Guide.
3Inspect your cables for damage. Contact the vendor to replace any damaged cables.
4Disconnect and re-connect the power adaptor to the EMG2881-T20A.
5If the problem continues, contact the vendor.
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12.3 EMG2881-T20A Access and Login
I don’t know the IP address of my EMG2881-T20A.
1The default IP address of the EMG2881-T20A in Router Mode is 192.168.1.1.
2If you changed the IP address and have forgotten it, you might get the IP address of the EMG2881-T20A
in Router Mode by looking up the IP address of the default gateway for your computer. To do this in most
Windows computers, click Start > Run, enter cmd, and then enter ipconfig. The IP address of the Default
Gateway might be the IP address of the EMG2881-T20A (it depends on the network), so enter this IP
address in your Internet browser.
3Reset your EMG2881-T20A to change all settings back to their default. This means your current settings
are lost. See Section 12.5 on page 109 in the Troubleshooting for information on resetting your EMG2881-
T20A.
I forgot the password.
1The default password is the factory default (see the device label).
2If this does not work, you have to reset the device to its factory defaults. See Section 12.5 on page 109.
I cannot see or access the Login screen in the Web Configurator.
1Make sure you are using the correct IP address.
• The default IP address of the EMG2881-T20A in Router Mode is 192.168.1.1.
• If you changed the IP address (Section 8.4 on page 71), use the new IP address.
• If you changed the IP address and have forgotten it, see the troubleshooting suggestions for I don’t
know the IP address of my EMG2881-T20A.
2Check the hardware connections, and make sure the LEDs are behaving as expected. See the Quick
Start Guide.
3Make sure your Internet browser does not block pop-up windows and has JavaScript and Java
enabled. See Appendix A on page 112.
4Make sure your computer is in the same subnet as the EMG2881-T20A. (If you know that there are routers
between your computer and the EMG2881-T20A, skip this step.)
• If there is a DHCP server on your network, make sure your computer is using a dynamic IP address.
See Section 8.4 on page 71.
• If there is no DHCP server on your network, make sure your computer’s IP address is in the same
subnet as the EMG2881-T20A. See Section 8.4 on page 71.
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5Reset the device to its factory defaults, and try to access the EMG2881-T20A with the default IP address.
See Section 1.5.6 on page 14.
6If the problem continues, contact the network administrator or vendor, or try one of the advanced
suggestions.
Advanced Suggestions
• Try to access the EMG2881-T20A using another service, such as Telnet. If you can access the
EMG2881-T20A, check the remote management settings and firewall rules to find out why the
EMG2881-T20A does not respond to HTTP.
• If your computer is connected to the WAN port or is connected wirelessly, use a computer that is
connected to a LAN/ETHERNET port.
I can see the Login screen, but I cannot log in to the EMG2881-T20A.
1Make sure you have entered the password correctly. The default password is the factory default (see
the device label). This field is case-sensitive, so make sure [Caps Lock] is not on.
2This can happen when you fail to log out properly from your last session. Try logging in again after 10
minutes.
3Disconnect and re-connect the power adaptor or cord to the EMG2881-T20A.
4If this does not work, you have to reset the device to its factory defaults. See Section 12.5 on page 109.
12.4 Internet Access
I cannot access the Internet.
1Check the hardware connections, and make sure the LEDs are behaving as expected. See the Quick
Start Guide.
2Make sure the WAN port is connected to a broadband modem or router with Internet access. Your
computer and the EMG2881-T20A should be in the same subnet.
3Make sure you entered your ISP account information correctly in the wizard or the WAN screen. These
fields are case-sensitive, so make sure [Caps Lock] is not on.
4If you are trying to access the Internet wirelessly, make sure the wireless settings in the wireless client are
the same as the settings in the AP.
5Disconnect all the cables from your device, and follow the directions in the Quick Start Guide again.
6If the problem continues, contact your ISP.
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I cannot access the Internet anymore. I had access to the Internet (with the EMG2881-T20A), but
my Internet connection is not available anymore.
1Check the hardware connections, and make sure the LEDs are behaving as expected. See the Quick
Start Guide and Section 1.5 on page 12.
2Reboot the EMG2881-T20A.
3If the problem continues, contact your ISP.
The Internet connection is slow or intermittent.
1There might be a lot of traffic on the network. Look at the LEDs, and check Section 1.5 on page 12. If the
EMG2881-T20A is sending or receiving a lot of information, try closing some programs that use the
Internet, especially peer-to-peer applications.
2Check the signal strength. If the signal strength is low, try moving the EMG2881-T20A closer to the AP if
possible, and look around to see if there are any devices that might be interfering with the wireless
network (for example, microwaves, other wireless networks, and so on).
3Reboot the EMG2881-T20A.
4If the problem continues, contact the network administrator or vendor, or try one of the advanced
suggestions.
Advanced Suggestion
• Check the settings for QoS. If it is disabled, you might consider activating it.
12.5 Resetting the EMG2881-T20A to Its Factory Defaults
If you reset the EMG2881-T20A, you lose all of the changes you have made. The EMG2881-T20A re-loads
its default settings. You have to make all of your changes again.
You will lose all of your changes when you push the RESET button.
To reset the EMG2881-T20A:
1Make sure the power LED is on.
2Press the RESET button for one to four seconds to restart/reboot the EMG2881-T20A.
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3Press the RESET button for longer than five seconds to set the EMG2881-T20A back to its factory-default
configurations.
If the EMG2881-T20A restarts automatically, wait for the EMG2881-T20A to finish restarting, and log in to
the Web Configurator. The password is reset to the factory default (see the device label).
If the EMG2881-T20A does not restart automatically, disconnect and reconnect the EMG2881-T20A’s
power. Then, follow the directions above again.
12.6 Wireless Connections
I cannot access the EMG2881-T20A or ping any computer from the WLAN.
1Make sure the wireless LAN is enabled on the EMG2881-T20A.
2Make sure the wireless adapter on your computer is working properly.
3Make sure the wireless adapter installed on your computer is IEEE 802.11 compatible and supports the
same wireless standard as the EMG2881-T20A.
4Make sure your computer (with a wireless adapter installed) is within the transmission range of the
EMG2881-T20A.
5Check that both the EMG2881-T20A and the wireless adapter on your computer are using the same
wireless and wireless security settings.
6Make sure traffic between the WLAN and the LAN is not blocked by the firewall on the EMG2881-T20A.
7Make sure you allow the EMG2881-T20A to be remotely accessed through the WLAN interface. Check
your remote management settings.
•See the chapter on Wireless LAN in the User’s Guide for more information.
What factors may cause intermittent or unstabled wireless connection? How can I solve this
problem?
The following factors may cause interference:
• Obstacles: walls, ceilings, furniture, and so on.
• Building Materials: metal doors, aluminum studs.
• Electrical devices: microwaves, monitors, electric motors, cordless phones, and other wireless devices.
To optimize the speed and quality of your wireless connection, you can:
• Move your wireless device closer to the AP if the signal strength is low.
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• Reduce wireless interference that may be caused by other wireless networks or surrounding wireless
electronics such as cordless phones.
• Place the AP where there are minimum obstacles (such as walls and ceilings) between the AP and
the wireless client.
• Reduce the number of wireless clients connecting to the same AP simultaneously, or add additional
APs if necessary.
• Try closing some programs that use the Internet, especially peer-to-peer applications. If the wireless
client is sending or receiving a lot of information, it may have too many programs open that use the
Internet.
• Position the antennas for best reception. If the AP is placed on a table or floor, point the antennas
upwards. If the AP is placed at a high position, point the antennas downwards. Try pointing the
antennas in different directions and check which provides the strongest signal to the wireless clients.
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APPENDIX A
Pop-up Windows, JavaScript and
Java Permissions
In order to use the web configurator you need to allow:
• Web browser pop-up windows from your device.
• JavaScript (enabled by default).
• Java permissions (enabled by default).
Note: The screens used below belong to Internet Explorer version 6, 7 and 8. Screens for other
Internet Explorer versions may vary.
Internet Explorer Pop-up Blockers
You may have to disable pop-up blocking to log into your device.
Either disable pop-up blocking (enabled by default in Windows XP SP (Service Pack) 2) or allow pop-up
blocking and create an exception for your device’s IP address.
Disable Pop-up Blockers
1In Internet Explorer, select Tools, Pop-up Blocker and then select Turn Off Pop-up Blocker.
Figure 68 Pop-up Blocker
You can also check if pop-up blocking is disabled in the Pop-up Blocker section in the Privacy tab.
1In Internet Explorer, select Tools, Internet Options, Privacy.
2Clear the Block pop-ups check box in the Pop-up Blocker section of the screen. This disables any web
pop-up blockers you may have enabled.
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Figure 69 Internet Options: Privacy
3Click Apply to save this setting.
Enable Pop-up Blockers with Exceptions
Alternatively, if you only want to allow pop-up windows from your device, see the following steps.
1In Internet Explorer, select Tools, Internet Options and then the Privacy tab.
2Select Settings…to open the Pop-up Blocker Settings screen.
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Figure 70 Internet Options: Privacy
3Type the IP address of your device (the web page that you do not want to have blocked) with the prefix
“http://”. For example, http://192.168.167.1.
4Click Add to move the IP address to the list of Allowed sites.
Figure 71 Pop-up Blocker Settings
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5Click Close to return to the Privacy screen.
6Click Apply to save this setting.
JavaScript
If pages of the web configurator do not display properly in Internet Explorer, check that JavaScript are
allowed.
1In Internet Explorer, click Tools, Internet Options and then the Security tab.
Figure 72 Internet Options: Security
2Click the Custom Level... button.
3Scroll down to Scripting.
4Under Active scripting make sure that Enable is selected (the default).
5Under Scripting of Java applets make sure that Enable is selected (the default).
6Click OK to close the window.
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Figure 73 Security Settings - Java Scripting
Java Permissions
1From Internet Explorer, click Tools, Internet Options and then the Security tab.
2Click the Custom Level... button.
3Scroll down to Microsoft VM.
4Under Java permissions make sure that a safety level is selected.
5Click OK to close the window.
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Figure 74 Security Settings - Java
JAVA (Sun)
1From Internet Explorer, click Tools, Internet Options and then the Advanced tab.
2Make sure that Use Java 2 for <applet> under Java (Sun) is selected.
3Click OK to close the window.
Figure 75 Java (Sun)
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Mozilla Firefox
Mozilla Firefox 2.0 screens are used here. Screens for other versions may vary slightly. The steps below
apply to Mozilla Firefox 3.0 as well.
You can enable Java, Javascript and pop-ups in one screen. Click Tools, then click Options in the
screen that appears.
Figure 76 Mozilla Firefox: TOOLS > Options
Click Content to show the screen below. Select the check boxes as shown in the following screen.
Figure 77 Mozilla Firefox Content Security
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Opera
Opera 10 screens are used here. Screens for other versions may vary slightly.
Allowing Pop-Ups
From Opera, click Tools, then Preferences. In the General tab, go to Choose how you prefer to handle
pop-ups and select Open all pop-ups.
Figure 78 Opera: Allowing Pop-Ups
Enabling Java
From Opera, click Tools, then Preferences. In the Advanced tab, select Content from the left-side menu.
Select the check boxes as shown in the following screen.
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Figure 79 Opera: Enabling Java
To customize JavaScript behavior in the Opera browser, click JavaScript Options.
Figure 80 Opera: JavaScript Options
Select the items you want Opera’s JavaScript to apply.
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APPENDIX B
Setting Up Your Computer’s IP
Address
Note: Your specific EMG2881-T20A may not support all of the operating systems described in
this appendix. See the product specifications for more information about which
operating systems are supported.
This appendix shows you how to configure the IP settings on your computer in order for it to be able to
communicate with the other devices on your network. Windows Vista/XP/2000, Mac OS 9/OS X, and all
versions of UNIX/LINUX include the software components you need to use TCP/IP on your computer.
If you manually assign IP information instead of using a dynamic IP, make sure that your network’s
computers have IP addresses that place them in the same subnet.
In this appendix, you can set up an IP address for:
•Windows XP/NT/2000 on page 121
•Windows Vista on page 124
•Windows 7 on page 127
•Mac OS X: 10.3 and 10.4 on page 132
•Mac OS X: 10.5 and 10.6 on page 135
•Linux: Ubuntu 8 (GNOME) on page 138
•Linux: openSUSE 10.3 (KDE) on page 142
Windows XP/NT/2000
The following example uses the default Windows XP display theme but can also apply to Windows 2000
and Windows NT.
1Click Start > Control Panel.
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2In the Control Panel, click the Network Connections icon.
3Right-click Local Area Connection and then select Properties.
4On the General tab, select Internet Protocol (TCP/IP) and then click Properties.
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5The Internet Protocol TCP/IP Properties window opens.
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6Select Obtain an IP address automatically if your network administrator or ISP assigns your IP address
dynamically.
Select Use the following IP Address and fill in the IP address, Subnet mask, and Default gateway fields if
you have a static IP address that was assigned to you by your network administrator or ISP. You may also
have to enter a Preferred DNS server and an Alternate DNS server, if that information was provided.
7Click OK to close the Internet Protocol (TCP/IP) Properties window.
8Click OK to close the Local Area Connection Properties window.
Verifying Settings
1Click Start > All Programs > Accessories > Command Prompt.
2In the Command Prompt window, type "ipconfig" and then press [ENTER].
You can also go to Start > Control Panel > Network Connections, right-click a network connection, click
Status and then click the Support tab to view your IP address and connection information.
Windows Vista
This section shows screens from Windows Vista Professional.
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1Click Start > Control Panel.
2In the Control Panel, click the Network and Internet icon.
3Click the Network and Sharing Center icon.
4Click Manage network connections.
5Right-click Local Area Connection and then select Properties.
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Note: During this procedure, click Continue whenever Windows displays a screen saying that
it needs your permission to continue.
6Select Internet Protocol Version 4 (TCP/IPv4) and then select Properties.
7The Internet Protocol Version 4 (TCP/IPv4) Properties window opens.
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8Select Obtain an IP address automatically if your network administrator or ISP assigns your IP address
dynamically.
Select Use the following IP Address and fill in the IP address, Subnet mask, and Default gateway fields if
you have a static IP address that was assigned to you by your network administrator or ISP. You may also
have to enter a Preferred DNS server and an Alternate DNS server, if that information was provided.Click
Advanced.
9Click OK to close the Internet Protocol (TCP/IP) Properties window.
10 Click OK to close the Local Area Connection Properties window.
Verifying Settings
1Click Start > All Programs > Accessories > Command Prompt.
2In the Command Prompt window, type "ipconfig" and then press [ENTER].
You can also go to Start > Control Panel > Network Connections, right-click a network connection, click
Status and then click the Support tab to view your IP address and connection information.
Windows 7
This section shows screens from Windows 7 Enterprise.
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1Click Start > Control Panel.
2In the Control Panel, click View network status and tasks under the Network and Internet category.
3Click Change adapter settings.
4Double click Local Area Connection and then select Properties.
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Note: During this procedure, click Continue whenever Windows displays a screen saying that
it needs your permission to continue.
5Select Internet Protocol Version 4 (TCP/IPv4) and then select Properties.
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6The Internet Protocol Version 4 (TCP/IPv4) Properties window opens.
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7Select Obtain an IP address automatically if your network administrator or ISP assigns your IP address
dynamically.
Select Use the following IP Address and fill in the IP address, Subnet mask, and Default gateway fields if
you have a static IP address that was assigned to you by your network administrator or ISP. You may also
have to enter a Preferred DNS server and an Alternate DNS server, if that information was provided. Click
Advanced if you want to configure advanced settings for IP, DNS and WINS.
8Click OK to close the Internet Protocol (TCP/IP) Properties window.
9Click OK to close the Local Area Connection Properties window.
Verifying Settings
1Click Start > All Programs > Accessories > Command Prompt.
2In the Command Prompt window, type "ipconfig" and then press [ENTER].
3The IP settings are displayed as follows.
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Mac OS X: 10.3 and 10.4
The screens in this section are from Mac OS X 10.4 but can also apply to 10.3.
1Click Apple > System Preferences.
2In the System Preferences window, click the Network icon.
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3When the Network preferences pane opens, select Built-in Ethernet from the network connection type
list, and then click Configure.
4For dynamically assigned settings, select Using DHCP from the Configure IPv4 list in the TCP/IP tab.
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5For statically assigned settings, do the following:
•From the Configure IPv4 list, select Manually.
• In the IP Address field, type your IP address.
• In the Subnet Mask field, type your subnet mask.
• In the Router field, type the IP address of your device.
6Click Apply Now and close the window.
Verifying Settings
Check your TCP/IP properties by clicking Applications > Utilities > Network Utilities, and then selecting
the appropriate Network Interface from the Info tab.
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Figure 81 Mac OS X 10.4: Network Utility
Mac OS X: 10.5 and 10.6
The screens in this section are from Mac OS X 10.5 but can also apply to 10.6.
1Click Apple > System Preferences.
2In System Preferences, click the Network icon.
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3When the Network preferences pane opens, select Ethernet from the list of available connection types.
4From the Configure list, select Using DHCP for dynamically assigned settings.
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5For statically assigned settings, do the following:
•From the Configure list, select Manually.
• In the IP Address field, enter your IP address.
• In the Subnet Mask field, enter your subnet mask.
• In the Router field, enter the IP address of your EMG2881-T20A.
6Click Apply and close the window.
Verifying Settings
Check your TCP/IP properties by clicking Applications > Utilities > Network Utilities, and then selecting
the appropriate Network interface from the Info tab.
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Figure 82 Mac OS X 10.5: Network Utility
Linux: Ubuntu 8 (GNOME)
This section shows you how to configure your computer’s TCP/IP settings in the GNU Object Model
Environment (GNOME) using the Ubuntu 8 Linux distribution. The procedure, screens and file locations
may vary depending on your specific distribution, release version, and individual configuration. The
following screens use the default Ubuntu 8 installation.
Note: Make sure you are logged in as the root administrator.
Follow the steps below to configure your computer IP address in GNOME:
1Click System > Administration > Network.
2When the Network Settings window opens, click Unlock to open the Authenticate window. (By default,
the Unlock button is greyed out until clicked.) You cannot make changes to your configuration unless
you first enter your admin password.
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3In the Authenticate window, enter your admin account name and password then click the Authenticate
button.
4In the Network Settings window, select the connection that you want to configure, then click Properties.
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5The Properties dialog box opens.
• In the Configuration list, select Automatic Configuration (DHCP) if you have a dynamic IP address.
• In the Configuration list, select Static IP address if you have a static IP address. Fill in the IP address,
Subnet mask, and Gateway address fields.
6Click OK to save the changes and close the Properties dialog box and return to the Network Settings
screen.
7If you know your DNS server IP address(es), click the DNS tab in the Network Settings window and then
enter the DNS server information in the fields provided.
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8Click the Close button to apply the changes.
Verifying Settings
Check your TCP/IP properties by clicking System > Administration > Network Tools, and then selecting
the appropriate Network device from the Devices tab. The Interface Statistics column shows data if your
connection is working properly.
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Figure 83 Ubuntu 8: Network Tools
Linux: openSUSE 10.3 (KDE)
This section shows you how to configure your computer’s TCP/IP settings in the K Desktop Environment
(KDE) using the openSUSE 10.3 Linux distribution. The procedure, screens and file locations may vary
depending on your specific distribution, release version, and individual configuration. The following
screens use the default openSUSE 10.3 installation.
Note: Make sure you are logged in as the root administrator.
Follow the steps below to configure your computer IP address in the KDE:
1Click K Menu > Computer > Administrator Settings (YaST).
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2When the Run as Root - KDE su dialog opens, enter the admin password and click OK.
3When the YaST Control Center window opens, select Network Devices and then click the Network Card
icon.
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4When the Network Settings window opens, click the Overview tab, select the appropriate connection
Name from the list, and then click the Configure button.
5When the Network Card Setup window opens, click the Address tab
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Figure 84 openSUSE 10.3: Network Card Setup
6Select Dynamic Address (DHCP) if you have a dynamic IP address.
Select Statically assigned IP Address if you have a static IP address. Fill in the IP address, Subnet mask,
and Hostname fields.
7Click Next to save the changes and close the Network Card Setup window.
8If you know your DNS server IP address(es), click the Hostname/DNS tab in Network Settings and then
enter the DNS server information in the fields provided.
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9Click Finish to save your settings and close the window.
Verifying Settings
Click the KNetwork Manager icon on the Task bar to check your TCP/IP properties. From the Options sub-
menu, select Show Connection Information.
Figure 85 openSUSE 10.3: KNetwork Manager
When the Connection Status - KNetwork Manager window opens, click the Statistics tab to see if your
connection is working properly.
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Figure 86 openSUSE: Connection Status - KNetwork Manager
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APPENDIX C
Common Services
The following table lists some commonly-used services and their associated protocols and port numbers.
For a comprehensive list of port numbers, ICMP type/code numbers and services, visit the IANA (Internet
Assigned Number Authority) web site.
•Name: This is a short, descriptive name for the service. You can use this one or create a different one,
if you like.
•Protocol: This is the type of IP protocol used by the service. If this is TCP/UDP, then the service uses the
same port number with TCP and UDP. If this is USER-DEFINED, the Port(s) is the IP protocol number, not
the port number.
•Port(s): This value depends on the Protocol. Please refer to RFC 1700 for further information about port
numbers.
•If the Protocol is TCP, UDP, or TCP/UDP, this is the IP port number.
•If the Protocol is USER, this is the IP protocol number.
•Description: This is a brief explanation of the applications that use this service or the situations in which
this service is used.
Table 47 Commonly Used Services
NAME PROTOCOL PORT(S) DESCRIPTION
AH (IPSEC_TUNNEL) User-Defined 51 The IPSEC AH (Authentication Header) tunneling
protocol uses this service.
AIM/New-ICQ TCP 5190 AOL’s Internet Messenger service. It is also used as a
listening port by ICQ.
AUTH TCP 113 Authentication protocol used by some servers.
BGP TCP 179 Border Gateway Protocol.
BOOTP_CLIENT UDP 68 DHCP Client.
BOOTP_SERVER UDP 67 DHCP Server.
CU-SEEME TCP
UDP
7648
24032
A popular videoconferencing solution from White
Pines Software.
DNS TCP/UDP 53 Domain Name Server, a service that matches web
names (for example www.zyxel.com) to IP numbers.
ESP (IPSEC_TUNNEL) User-Defined 50 The IPSEC ESP (Encapsulation Security Protocol)
tunneling protocol uses this service.
FINGER TCP 79 Finger is a UNIX or Internet related command that can
be used to find out if a user is logged on.
FTP TCP
TCP
20
21
File Transfer Program, a program to enable fast
transfer of files, including large files that may not be
possible by e-mail.
H.323 TCP 1720 NetMeeting uses this protocol.
HTTP TCP 80 Hyper Text Transfer Protocol - a client/server protocol
for the world wide web.
HTTPS TCP 443 HTTPS is a secured http session often used in e-
commerce.
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ICMP User-Defined 1Internet Control Message Protocol is often used for
diagnostic or routing purposes.
ICQ UDP 4000 This is a popular Internet chat program.
IGMP (MULTICAST) User-Defined 2Internet Group Management Protocol is used when
sending packets to a specific group of hosts.
IKE UDP 500 The Internet Key Exchange algorithm is used for key
distribution and management.
IRC TCP/UDP 6667 This is another popular Internet chat program.
MSN Messenger TCP 1863 Microsoft Networks’ messenger service uses this
protocol.
NEW-ICQ TCP 5190 An Internet chat program.
NEWS TCP 144 A protocol for news groups.
NFS UDP 2049 Network File System - NFS is a client/server distributed
file service that provides transparent file sharing for
network environments.
NNTP TCP 119 Network News Transport Protocol is the delivery
mechanism for the USENET newsgroup service.
PING User-Defined 1Packet INternet Groper is a protocol that sends out
ICMP echo requests to test whether or not a remote
host is reachable.
POP3 TCP 110 Post Office Protocol version 3 lets a client computer
get e-mail from a POP3 server through a temporary
connection (TCP/IP or other).
PPTP TCP 1723 Point-to-Point Tunneling Protocol enables secure
transfer of data over public networks. This is the
control channel.
PPTP_TUNNEL (GRE) User-Defined 47 PPTP (Point-to-Point Tunneling Protocol) enables
secure transfer of data over public networks. This is the
data channel.
RCMD TCP 512 Remote Command Service.
REAL_AUDIO TCP 7070 A streaming audio service that enables real time
sound over the web.
REXEC TCP 514 Remote Execution Daemon.
RLOGIN TCP 513 Remote Login.
RTELNET TCP 107 Remote Telnet.
RTSP TCP/UDP 554 The Real Time Streaming (media control) Protocol
(RTSP) is a remote control for multimedia on the
Internet.
SFTP TCP 115 Simple File Transfer Protocol.
SMTP TCP 25 Simple Mail Transfer Protocol is the message-
exchange standard for the Internet. SMTP enables
you to move messages from one e-mail server to
another.
SNMP TCP/UDP 161 Simple Network Management Program.
SNMP-TRAPS TCP/UDP 162 Traps for use with the SNMP (RFC:1215).
SQL-NET TCP 1521 Structured Query Language is an interface to access
data on many different types of database systems,
including mainframes, midrange systems, UNIX
systems and network servers.
Table 47 Commonly Used Services (continued)
NAME PROTOCOL PORT(S) DESCRIPTION
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SSH TCP/UDP 22 Secure Shell Remote Login Program.
STRM WORKS UDP 1558 Stream Works Protocol.
SYSLOG UDP 514 Syslog allows you to send system logs to a UNIX server.
TACACS UDP 49 Login Host Protocol used for (Terminal Access
Controller Access Control System).
TELNET TCP 23 Telnet is the login and terminal emulation protocol
common on the Internet and in UNIX environments. It
operates over TCP/IP networks. Its primary function is
to allow users to log into remote host systems.
TFTP UDP 69 Trivial File Transfer Protocol is an Internet file transfer
protocol similar to FTP, but uses the UDP (User
Datagram Protocol) rather than TCP (Transmission
Control Protocol).
VDOLIVE TCP 7000 Another videoconferencing solution.
Table 47 Commonly Used Services (continued)
NAME PROTOCOL PORT(S) DESCRIPTION
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APPENDIX D
Customer Support
In the event of problems that cannot be solved by using this manual, you should contact your vendor. If
you cannot contact your vendor, then contact a Zyxel office for the region in which you bought the
device.
See http://www.zyxel.com/homepage.shtml and also
http://www.zyxel.com/about_zyxel/zyxel_worldwide.shtml for the latest information.
Please have the following information ready when you contact an office.
Required Information
• Product model and serial number.
• Warranty Information.
• Date that you received your device.
• Brief description of the problem and the steps you took to solve it.
Corporate Headquarters (Worldwide)
Taiwan
• Zyxel Communications Corporation
• http://www.zyxel.com
Asia
China
• Zyxel Communications (Shanghai) Corp.
Zyxel Communications (Beijing) Corp.
Zyxel Communications (Tianjin) Corp.
• http://www.zyxel.cn
India
•Zyxel Technology India Pvt Ltd
• http://www.zyxel.in
Kazakhstan
•Zyxel Kazakhstan
• http://www.zyxel.kz
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Korea
• Zyxel Korea Corp.
• http://www.zyxel.kr
Malaysia
• Zyxel Malaysia Sdn Bhd.
• http://www.zyxel.com.my
Pakistan
• Zyxel Pakistan (Pvt.) Ltd.
• http://www.zyxel.com.pk
Philippines
• Zyxel Philippines
• http://www.zyxel.com.ph
Singapore
• Zyxel Singapore Pte Ltd.
• http://www.zyxel.com.sg
Taiwan
• Zyxel Communications Corporation
• http://www.zyxel.com/tw/zh/
Thailand
• Zyxel Thailand Co., Ltd
• http://www.zyxel.co.th
Vietnam
• Zyxel Communications Corporation-Vietnam Office
• http://www.zyxel.com/vn/vi
Europe
Austria
•Zyxel Deutschland GmbH
• http://www.zyxel.de
Belarus
•Zyxel BY
• http://www.zyxel.by
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153
Belgium
• Zyxel Communications B.V.
• http://www.zyxel.com/be/nl/
• http://www.zyxel.com/be/fr/
Bulgaria
•Zyxel България
• http://www.zyxel.com/bg/bg/
Czech Republic
• Zyxel Communications Czech s.r.o
• http://www.zyxel.cz
Denmark
• Zyxel Communications A/S
• http://www.zyxel.dk
Estonia
• Zyxel Estonia
• http://www.zyxel.com/ee/et/
Finland
• Zyxel Communications
• http://www.zyxel.fi
France
•Zyxel France
• http://www.zyxel.fr
Germany
•Zyxel Deutschland GmbH
• http://www.zyxel.de
Hungary
• Zyxel Hungary & SEE
• http://www.zyxel.hu
Italy
• Zyxel Communications Italy
• http://www.zyxel.it/
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Latvia
•Zyxel Latvia
• http://www.zyxel.com/lv/lv/homepage.shtml
Lithuania
•Zyxel Lithuania
• http://www.zyxel.com/lt/lt/homepage.shtml
Netherlands
• Zyxel Benelux
• http://www.zyxel.nl
Norway
• Zyxel Communications
• http://www.zyxel.no
Poland
• Zyxel Communications Poland
• http://www.zyxel.pl
Romania
• Zyxel Romania
• http://www.zyxel.com/ro/ro
Russia
• Zyxel Russia
• http://www.zyxel.ru
Slovakia
• Zyxel Communications Czech s.r.o. organizacna zlozka
• http://www.zyxel.sk
Spain
• Zyxel Communications ES Ltd
• http://www.zyxel.es
Sweden
• Zyxel Communications
• http://www.zyxel.se
Switzerland
•Studerus AG
Appendix D Customer Support
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• http://www.zyxel.ch/
Turkey
• Zyxel Turkey A.S.
• http://www.zyxel.com.tr
UK
• Zyxel Communications UK Ltd.
• http://www.zyxel.co.uk
Ukraine
•Zyxel Ukraine
• http://www.ua.zyxel.com
Latin America
Argentina
• Zyxel Communication Corporation
• http://www.zyxel.com/ec/es/
Brazil
• Zyxel Communications Brasil Ltda.
• https://www.zyxel.com/br/pt/
Ecuador
• Zyxel Communication Corporation
• http://www.zyxel.com/ec/es/
Middle East
Israel
• Zyxel Communication Corporation
• http://il.zyxel.com/homepage.shtml
Middle East
• Zyxel Communication Corporation
• http://www.zyxel.com/me/en/
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North America
USA
• Zyxel Communications, Inc. - North America Headquarters
• http://www.zyxel.com/us/en/
Oceania
Australia
• Zyxel Communications Corporation
• http://www.zyxel.com/au/en/
Africa
South Africa
• Nology (Pty) Ltd.
• http://www.zyxel.co.za
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APPENDIX E
Legal Information
Copyright
Copyright © 2018 by Zyxel Communications Corporation.
The contents of this publication may not be reproduced in any part or as a whole, transcribed, stored in a retrieval system, translated into any
language, or transmitted in any form or by any means, electronic, mechanical, magnetic, optical, chemical, photocopying, manual, or
otherwise, without the prior written permission of Zyxel Communications Corporation.
Published by Zyxel Communications Corporation. All rights reserved.
Disclaimer
Zyxel does not assume any liability arising out of the application or use of any products, or software described herein. Neither does it convey any
license under its patent rights nor the patent rights of others. Zyxel further reserves the right to make changes in any products described herein
without notice. This publication is subject to change without notice.
Regulatory Notice and Statement
UNITED STATES of AMERICA
The following information applies if you use the product within USA area.
FCC EMC Statement
• The device complies with Part 15 of FCC rules. Operation is subject to the following two conditions:
(1) This device may not cause harmful interference, and
(2) This device must accept any interference received, including interference that may cause undesired operation.
• Changes or modifications not expressly approved by the party responsible for compliance could void the user’s authority to operate the
device.
• This product has been tested and complies with the specifications 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 device generates, uses, and
can radiate radio frequency energy and, if not installed and used according to 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 device does cause harmful interference to radio or television reception, which is found by turning the device 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 devices
• Connect the equipment to an outlet other than the receiver’s
• Consult a dealer or an experienced radio/TV technician for assistance
The following information applies if you use the product with RF function within USA area.
FCC Radiation Exposure Statement
• This device complies with FCC RF radiation exposure limits set forth for an uncontrolled environment.
• This transmitter must be at least 23 cm from the user and must not be co-located or operating in conjunction with any other antenna or
transmitter.
• Operation of this device is restricted to indoor use only, except for relevant user's manual mention that this device can be installed into the
external environment.
CANADA
The following information applies if you use the product within Canada area.
Industry Canada ICES Statement
CAN ICES-3 (B)/NMB-3(B)
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158
Industry Canada RSS-GEN & RSS-247 statement
• This device complies with Industry Canada license-exempt RSS standard(s). Operation is subject to the following two conditions: (1) this
device may not cause interference, and (2) this device must accept any interference, including interference that may cause undesired
operation of the device.
• This radio transmitter (2468C-EMG2881T20A) has been approved by Industry Canada to operate with the antenna types listed below with the
maximum permissible gain and required antenna impedance for each antenna type indicated. Antenna types not included in this list,
having a gain greater than the maximum gain indicated for that type, are strictly prohibited for use with this device.
Antenna Information
If the product with 5G wireless function operating in 5150-5250 MHz and 5725-5850 MHz, the following attention must be paid,
• The device for operation in the band 5150-5250 MHz is only for indoor use to reduce the potential for harmful interference to co-channel
mobile satellite systems.
• For devices with detachable antenna(s), the maximum antenna gain permitted for devices in the band 5725-5850 MHz shall be such that the
equipment still complies with the e.i.r.p. limits specified for point-to-point and non-point-to-point operation as appropriate; and
• The worst-case tilt angle(s) necessary to remain compliant with the e.i.r.p. elevation mask requirement set forth in Section 6.2.2(3) of RSS 247
shall be clearly indicated.
If the product with 5G wireless function operating in 5250-5350 MHz and 5470-5725 MHz , the following attention must be paid.
• For devices with detachable antenna(s), the maximum antenna gain permitted for devices in the bands 5250-5350 MHz and 5470-5725 MHz
shall be such that the equipment still complies with the e.i.r.p. limit.
• Le présent appareil est conforme aux CNR d’Industrie Canada applicables aux appareils radio exempts de licence. L’exploitation est
autorisée aux deux conditions suivantes : (1) l’appareil ne doit pas produire de brouillage, et (2) l’utilisateur de l’appareil doit accepter tout
brouillage radioélectrique subi, même si le brouillage est susceptible d’en compromettre le fonctionnement.
• Le présent émetteur radio (2468C-EMG2881T20A) de modèle s'il fait partie du matériel de catégorieI) a été approuvé par Industrie Canada
pour fonctionner avec les types d'antenne énumérés ci-dessous et ayant un gain admissible maximal et l'impédance requise pour chaque
type d'antenne. Les types d'antenne non inclus dans cette liste, ou dont le gain est supérieur au gain maximal indiqué, sont strictement
interdits pour l'exploitation de l'émetteur.
Informations Antenne
Lorsque la fonction sans fil 5G fonctionnant en 5150-5250 MHz and 5725-5850 MHz est activée pour ce produit , il est nécessaire de porter une
attention particulière aux choses suivantes
• Les dispositifs fonctionnant dans la bande 5150-5250 MHz sont réservés uniquement pour une utilisation à l’intérieur afin de réduire les risques
de brouillage préjudiciable aux systèmes de satellites mobiles utilisant les mêmes canaux;
• Pour les dispositifs munis d’antennes amovibles, le gain maximal d'antenne permis (pour les dispositifs utilisant la bande de 5 725 à 5 850 MHz)
doit être conforme à la limite de la p.i.r.e. spécifiée pour l'exploitation point à point et l’exploitation non point à point, selon le cas;
• Les pires angles d’inclinaison nécessaires pour rester conforme à l’exigence de la p.i.r.e. applicable au masque d’élévation, et énoncée à la
section 6.2.2 3) du CNR-247, doivent être clairement indiqués.
Lorsque la fonction sans fil 5G fonctionnant en 5250-5350 MHz et 5470-5725 MHz est activée pour ce produit , il est nécessaire de porter une
attention particulière aux choses suivantes.
• Pour les dispositifs munis d’antennes amovibles, le gain maximal d'antenne permis pour les dispositifs utilisant les bandes de 5 250 à 5 350 MHz
et de 5 470 à 5 725 MHz doit être conforme à la limite de la p.i.r.e.
Industry Canada radiation exposure statement
This device complies with IC radiation exposure limits set forth for an uncontrolled environment. This device should be installed and operated
with a minimum distance of 25 cm between the radiator and your body.
Déclaration d’exposition aux radiations:
Cet équipement est conforme aux limites d’exposition aux rayonnements IC établies pour un environnement non contrôlé. Cet équipement doit
être installé et utilisé avec un minimum de 25 cm de distance entre la source de rayonnement et votre corps.
TYPE MANUFACTURER GAIN CONNECTOR
PCB CINGXIN 2.97 dBi (2.4~2.4835GHz)
2.99 dBi (5.15~5.85GHz)
i-pex(MHF)
PCB CINGXIN 2.75 dBi (2.4~2.4835GHz)
2.97 dBi (5.15~5.85GHz)
i-pex(MHF)
TYPE FABRICANT GAIN CONNECTEUR
PCB CINGXIN 2.97 dBi (2.4~2.4835GHz)
2.99 dBi (5.15~5.85GHz)
i-pex(MHF)
PCB CINGXIN 2.75 dBi (2.4~2.4835GHz)
2.97 dBi (5.15~5.85GHz)
i-pex(MHF)
Appendix E Legal Information
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159
EUROPEAN UNION
The following information applies if you use the product within the European Union.
Declaration of Conformity with Regard to EU Directive 2014/53/EU (Radio Equipment Directive, RED)
• Compliance information for 2.4GHz and/or 5GHz wireless products relevant to the EU and other Countries following the EU Directive 2014/53/
EU (RED). And this product may be used in all EU countries (and other countries following the EU Directive 2014/53/EU) without any limitation
except for the countries mentioned below table:
• In the majority of the EU and other European countries, the 5GHz bands have been made available for the use of wireless local area
networks (LANs). Later in this document you will find an overview of countries in which additional restrictions or requirements or both are
applicable. The requirements for any country may evolve. Zyxel recommends that you check with the local authorities for the latest status of
their national regulations for the 5GHz wireless LANs.
• If this device for operation in the band 5150-5350 MHz, it is for indoor use only.
• This equipment should be installed and operated with a minimum distance of 20cm between the radio equipment and your body.
Български
(Bulgarian)
С настоящото Zyxel декларира, че това оборудване е в съответствие със съществените изисквания и другите
приложими разпоредбите на Директива 2014/53/ЕC.
National Restrictions
• The Belgian Institute for Postal Services and Telecommunications (BIPT) must be notified of any outdoor wireless link
having a range exceeding 300 meters. Please check http://www.bipt.be for more details.
• Draadloze verbindingen voor buitengebruik en met een reikwijdte van meer dan 300 meter dienen aangemeld te
worden bij het Belgisch Instituut voor postdiensten en telecommunicatie (BIPT). Zie http://www.bipt.be voor meer
gegevens.
• Les liaisons sans fil pour une utilisation en extérieur d’une distance supérieure à 300 mètres doivent être notifiées à
l’Institut Belge des services Postaux et des Télécommunications (IBPT). Visitez http://www.ibpt.be pour de plus amples
détails.
Español
(Spanish)
Por medio de la presente Zyxel declara que el equipo cumple con los requisitos esenciales y cualesquiera otras
disposiciones aplicables o exigibles de la Directiva 2014/53/UE..
Čeština
(Czech)
Zyxel tímto prohlašuje, že tento zařízení je ve shodě se základními požadavky a dalšími příslušnými ustanoveními směrnice
2014/53/EU.
Dansk (Danish) Undertegnede Zyxel erklærer herved, at følgende udstyr udstyr overholder de væsentlige krav og øvrige relevante krav i
direktiv 2014/53/EU.
National Restrictions
• In Denmark, the band 5150 - 5350 MHz is also allowed for outdoor usage.
• I Danmark må frekvensbåndet 5150 - 5350 også anvendes udendørs.
Deutsch
(German)
Hiermit erklärt Zyxel, dass sich das Gerät Ausstattung in Übereinstimmung mit den grundlegenden Anforderungen und den
übrigen einschlägigen Bestimmungen der Richtlinie 2014/53/EU befindet.
Eesti keel
(Estonian)
Käesolevaga kinnitab Zyxel seadme seadmed vastavust direktiivi 2014/53/EL põhinõuetele ja nimetatud direktiivist
tulenevatele teistele asjakohastele sätetele.
Ελληνικά
(Greek)
ΜΕ ΤΗΝ ΠΑΡΟΥΣΑ Zyxel ∆ΗΛΩΝΕΙ ΟΤΙ εξοπλισμός ΣΥΜΜΟΡΦΩΝΕΤΑΙ ΠΡΟΣ ΤΙΣ ΟΥΣΙΩ∆ΕΙΣ ΑΠΑΙΤΗΣΕΙΣ ΚΑΙ ΤΙΣ ΛΟΙΠΕΣ ΣΧΕΤΙΚΕΣ
∆ΙΑΤΑΞΕΙΣ ΤΗΣ Ο∆ΗΓΙΑΣ 2014/53/EE.
English Hereby, Zyxel declares that this device is in compliance with the essential requirements and other relevant provisions of
Directive 2014/53/EU.
Français
(French)
Par la présente Zyxel déclare que l'appareil équipements est conforme aux exigences essentielles et aux autres dispositions
pertinentes de la directive 2014/53/UE.
Hrvatski
(Croatian)
Zyxel ovime izjavljuje da je radijska oprema tipa u skladu s Direktivom 2014/53/UE.
Íslenska
(Icelandic)
Hér með lýsir, Zyxel því yfir að þessi búnaður er í samræmi við grunnkröfur og önnur viðeigandi ákvæði tilskipunar 2014/53/
UE.
Italiano (Italian) Con la presente Zyxel dichiara che questo attrezzatura è conforme ai requisiti essenziali ed alle altre disposizioni pertinenti
stabilite dalla direttiva 2014/53/UE.
National Restrictions
• This product meets the National Radio Interface and the requirements specified in the National Frequency Allocation
Table for Italy. Unless this wireless LAN product is operating within the boundaries of the owner's property, its use requires
a “general authorization.” Please check http://www.sviluppoeconomico.gov.it/ for more details.
• Questo prodotto è conforme alla specifiche di Interfaccia Radio Nazionali e rispetta il Piano Nazionale di ripartizione
delle frequenze in Italia. Se non viene installato all 'interno del proprio fondo, l'utilizzo di prodotti Wireless LAN richiede
una “Autorizzazione Generale”. Consultare http://www.sviluppoeconomico.gov.it/ per maggiori dettagli.
Appendix E Legal Information
EMG2881-T20A User’s Guide
160
Notes:
• Although Norway, Switzerland and Liechtenstein are not EU member states, the EU Directive 2014/53/EU has also been implemented in those
countries.
• The regulatory limits for maximum output power are specified in EIRP. The EIRP level (in dBm) of a device can be calculated by adding the
gain of the antenna used (specified in dBi) to the output power available at the connector (specified in dBm).
Latviešu valoda
(Latvian)
Ar šo Zyxel deklarē, ka iekārtas atbilst Direktīvas 2014/53/ES būtiskajām prasībām un citiem ar to saistītajiem noteikumiem.
National Restrictions
• The outdoor usage of the 2.4 GHz band requires an authorization from the Electronic Communications Office. Please
check http://www.esd.lv for more details.
• 2.4 GHz frekvenèu joslas izmantoðanai ârpus telpâm nepiecieðama atïauja no Elektronisko sakaru direkcijas. Vairâk
informâcijas: http://www.esd.lv.
Lietuvių kalba
(Lithuanian)
Šiuo Zyxel deklaruoja, kad šis įranga atitinka esminius reikalavimus ir kitas 2014/53/ES Direktyvos nuostatas.
Magyar
(Hungarian)
Alulírott, Zyxel nyilatkozom, hogy a berendezés megfelel a vonatkozó alapvetõ követelményeknek és az 2014/53/EU
irányelv egyéb elõírásainak.
Malti (Maltese) Hawnhekk, Zyxel, jiddikjara li dan tagħmir jikkonforma mal-ħtiġijiet essenzjali u ma provvedimenti oħrajn relevanti li hemm
fid-Dirrettiva 2014/53/UE.
Nederlands
(Dutch)
Hierbij verklaart Zyxel dat het toestel uitrusting in overeenstemming is met de essentiële eisen en de andere relevante
bepalingen van richtlijn 2014/53/EU.
Polski (Polish) Niniejszym Zyxel oświadcza, że sprzęt jest zgodny z zasadniczymi wymogami oraz pozostałymi stosownymi postanowieniami
Dyrektywy 2014/53/UE.
Português
(Portuguese)
Zyxel declara que este equipamento está conforme com os requisitos essenciais e outras disposições da Directiva 2014/53/
UE.
Română
(Romanian)
Prin prezenta, Zyxel declară că acest echipament este în conformitate cu cerinţele esenţiale şi alte prevederi relevante ale
Directivei 2014/53/UE.
Slovenčina
(Slovak)
Zyxel týmto vyhlasuje, že zariadenia spĺňa základné požiadavky a všetky príslušné ustanovenia Smernice 2014/53/EÚ.
Slovenščina
(Slovene)
Zyxel izjavlja, da je ta oprema v skladu z bistvenimi zahtevami in ostalimi relevantnimi določili direktive 2014/53/EU.
Suomi (Finnish) Zyxel vakuuttaa täten että laitteet tyyppinen laite on direktiivin 2014/53/EU oleellisten vaatimusten ja sitä koskevien
direktiivin muiden ehtojen mukainen.
Svenska
(Swedish)
Härmed intygar Zyxel att denna utrustning står I överensstämmelse med de väsentliga egenskapskrav och övriga relevanta
bestämmelser som framgår av direktiv 2014/53/EU.
Norsk
(Norwegian)
Erklærer herved Zyxel at dette utstyret er I samsvar med de grunnleggende kravene og andre relevante bestemmelser I
direktiv 2014/53/EU.
Appendix E Legal Information
EMG2881-T20A User’s Guide
161
List of national codes
Safety Warnings
• Do not use this product near water, for example, in a wet basement or near a swimming pool.
• Do not expose your device to dampness, dust or corrosive liquids.
• Do not store things on the device.
• Do not obstruct the device ventilation slots as insufficient airflow may harm your device. For example, do not place the device in an
enclosed space such as a box or on a very soft surface such as a bed or sofa.
• Do not install, use, or service this device during a thunderstorm. There is a remote risk of electric shock from lightning.
• Connect ONLY suitable accessories to the device.
• Do not open the device or unit. Opening or removing covers can expose you to dangerous high voltage points or other risks.
• Only qualified service personnel should service or disassemble this device. Please contact your vendor for further information.
• Make sure to connect the cables to the correct ports.
• Place connecting cables carefully so that no one will step on them or stumble over them.
• Always disconnect all cables from this device before servicing or disassembling.
• Do not remove the plug and connect it to a power outlet by itself; always attach the plug to the power adaptor first before connecting it to
a power outlet.
• Do not allow anything to rest on the power adaptor or cord and do NOT place the product where anyone can walk on the power adaptor
or cord.
• Please use the provided or designated connection cables/power cables/ adaptors. Connect it to the right supply voltage (for example,
110V AC in North America or 230V AC in Europe). If the power adaptor or cord is damaged, it might cause electrocution. Remove it from the
device and the power source, repairing the power adapter or cord is prohibited. Contact your local vendor to order a new one.
• Do not use the device outside, and make sure all the connections are indoors. There is a remote risk of electric shock from lightning.
• CAUTION: Risk of explosion if battery is replaced by an incorrect type, dispose of used batteries according to the instruction. Dispose them at
the applicable collection point for the recycling of electrical and electronic devices. For detailed information about recycling of this
product, please contact your local city office, your household waste disposal service or the store where you purchased the product.
• The following warning statements apply, where the disconnect device is not incorporated in the device or where the plug on the power
supply cord is intended to serve as the disconnect device,
- For permanently connected devices, a readily accessible disconnect device shall be incorporated external to the device;
- For pluggable devices, the socket-outlet shall be installed near the device and shall be easily accessible.
Environment Statement
ErP (Energy-related Products)
Zyxel products put on the EU market in compliance with the requirement of the European Parliament and the Council published Directive 2009/
125/EC establishing a framework for the setting of ecodesign requirements for energy-related products (recast), so called as "ErP Directive
(Energy-related Products directive) as well as ecodesign requirement laid down in applicable implementing measures, power consumption has
satisfied regulation requirements which are:
• Network standby power consumption < 8W, and/or
• Off mode power consumption < 0.5W, and/or
• Standby mode power consumption < 0.5W.
(Wireless setting, please refer to "Wireless" chapter for more detail.)
European Union - Disposal and Recycling Information
The symbol below means that according to local regulations your product and/or its battery shall be disposed of separately from domestic
waste. If this product is end of life, take it to a recycling station designated by local authorities. At the time of disposal, the separate collection of
your product and/or its battery will help save natural resources and ensure that the environment is sustainable development.
COUNTRY ISO 3166 2 LETTER CODE COUNTRY ISO 3166 2 LETTER CODE
Austria AT Liechtenstein LI
Belgium BE Lithuania LT
Bulgaria BG Luxembourg LU
Croatia HR Malta MT
Cyprus CY Netherlands NL
Czech Republic CZ Norway NO
Denmark DK Poland PL
Estonia EE Portugal PT
Finland FI Romania RO
France FR Serbia RS
Germany DE Slovakia SK
Greece GR Slovenia SI
Hungary HU Spain ES
Iceland IS Switzerland CH
Ireland IE Sweden SE
Italy IT Turkey TR
Latvia LV United Kingdom GB
Appendix E Legal Information
EMG2881-T20A User’s Guide
162
Die folgende Symbol bedeutet, dass Ihr Produkt und/oder seine Batterie gemäß den örtlichen Bestimmungen getrennt vom Hausmüll entsorgt
werden muss. Wenden Sie sich an eine Recyclingstation, wenn dieses Produkt das Ende seiner Lebensdauer erreicht hat. Zum Zeitpunkt der
Entsorgung wird die getrennte Sammlung von Produkt und/oder seiner Batterie dazu beitragen, natürliche Ressourcen zu sparen und die Umwelt
und die menschliche Gesundheit zu schützen.
El símbolo de abajo indica que según las regulaciones locales, su producto y/o su batería deberán depositarse como basura separada de la
doméstica. Cuando este producto alcance el final de su vida útil, llévelo a un punto limpio. Cuando llegue el momento de desechar el
producto, la recogida por separado éste y/o su batería ayudará a salvar los recursos naturales y a proteger la salud humana y
medioambiental.
Le symbole ci-dessous signifie que selon les réglementations locales votre produit et/ou sa batterie doivent être éliminés séparément des ordures
ménagères. Lorsque ce produit atteint sa fin de vie, amenez-le à un centre de recyclage. Au moment de la mise au rebut, la collecte séparée
de votre produit et/ou de sa batterie aidera à économiser les ressources naturelles et protéger l'environnement et la santé humaine.
Il simbolo sotto significa che secondo i regolamenti locali il vostro prodotto e/o batteria deve essere smaltito separatamente dai rifiuti domestici.
Quando questo prodotto raggiunge la fine della vita di servizio portarlo a una stazione di riciclaggio. Al momento dello smaltimento, la raccolta
separata del vostro prodotto e/o della sua batteria aiuta a risparmiare risorse naturali e a proteggere l'ambiente e la salute umana.
Symbolen innebär att enligt lokal lagstiftning ska produkten och/eller dess batteri kastas separat från hushållsavfallet. När den här produkten når
slutet av sin livslängd ska du ta den till en återvinningsstation. Vid tiden för kasseringen bidrar du till en bättre miljö och mänsklig hälsa genom att
göra dig av med den på ett återvinningsställe.
台灣
以下訊息僅適用於產品具有無線功能且銷售至台灣地區
• 第十二條 經型式認證合格之低功率射頻電機，非經許可，公司，商號或使用者均不得擅自變更頻率、加大功率或變更原設計之特性及功能。
• 第十四條 低功率射頻電機之使用不得影響飛航安全及干擾合法通信；經發現有干擾現象時，應立即停用，並改善至無干擾時方得繼續使用。
前項合法通信，指依電信法規定作業之無線電通信。 低功率射頻電機須忍受合法通信或工業、科學及醫療用電波輻射性電機設備之干擾。
• 無線資訊傳輸設備忍受合法通信之干擾且不得干擾合法通信；如造成干擾，應立即停用， 俟無干擾之虞，始得繼續使用。
• 無線資訊傳設備的製造廠商應確保頻率穩定性，如依製造廠商使用手冊上所述正常操作， 發射的信號應維持於操作頻帶中
• 使用無線產品時，應避免影響附近雷達系統之操作。
• 若使用高增益指向性天線，該產品僅應用於固定式點對點系統。
以下訊息僅適用於產品屬於專業安裝並銷售至台灣地區
• 本器材須經專業工程人員安裝及設定，始得設置使用，且不得直接販售給一般消費者。
安全警告 - 為了您的安全，請先閱讀以下警告及指示 :
• 請勿將此產品接近水、火焰或放置在高溫的環境。
• 避免設備接觸 :
- 任何液體 - 切勿讓設備接觸水、雨水、高濕度、污水腐蝕性的液體或其他水份。
- 灰塵及污物 - 切勿接觸灰塵、污物、沙土、食物或其他不合適的材料。
• 雷雨天氣時，不要安裝，使用或維修此設備。有遭受電擊的風險。
• 切勿重摔或撞擊設備，並勿使用不正確的電源變壓器。
• 若接上不正確的電源變壓器會有爆炸的風險。
• 請勿隨意更換產品內的電池。
• 如果更換不正確之電池型式，會有爆炸的風險，請依製造商說明書處理使用過之電池。
• 請將廢電池丟棄在適當的電器或電子設備回收處。
• 請勿將設備解體。
• 請勿阻礙設備的散熱孔，空氣對流不足將會造成設備損害。
• 請插在正確的電壓供給插座 ( 如 : 北美 / 台灣電壓 110V AC，歐洲是 230V AC)。
Appendix E Legal Information
EMG2881-T20A User’s Guide
163
• 假若電源變壓器或電源變壓器的纜線損壞，請從插座拔除，若您還繼續插電使用，會有觸電死亡的風險。
• 請勿試圖修理電源變壓器或電源變壓器的纜線，若有毀損，請直接聯絡您購買的店家，購買一個新的電源變壓器。
• 請勿將此設備安裝於室外，此設備僅適合放置於室內。
• 請勿隨一般垃圾丟棄。
• 請參閱產品背貼上的設備額定功率。
• 請參考產品型錄或是彩盒上的作業溫度。
• 產品沒有斷電裝置或者採用電源線的插頭視為斷電裝置的一部分，以下警語將適用 :
- 對永久連接之設備， 在設備外部須安裝可觸及之斷電裝置；
- 對插接式之設備， 插座必須接近安裝之地點而且是易於觸及的。
About the Symbols
Various symbols are used in this product to ensure correct usage, to prevent danger to the user and others, and to prevent property damage.
The meaning of these symbols are described below. It is important that you read these descriptions thoroughly and fully understand the
contents.
Explanation of the Symbols
Viewing Certifications
Go to http://www.zyxel.com to view this product’s documentation and certifications.
Zyxel Limited Warranty
Zyxel warrants to the original end user (purchaser) that this product is free from any defects in material or workmanship for a specific period (the
Warranty Period) from the date of purchase. The Warranty Period varies by region. Check with your vendor and/or the authorized Zyxel local
distributor for details about the Warranty Period of this product. During the warranty period, and upon proof of purchase, should the product
have indications of failure due to faulty workmanship and/or materials, Zyxel will, at its discretion, repair or replace the defective products or
components without charge for either parts or labor, and to whatever extent it shall deem necessary to restore the product or components to
proper operating condition. Any replacement will consist of a new or re-manufactured functionally equivalent product of equal or higher value,
and will be solely at the discretion of Zyxel. This warranty shall not apply if the product has been modified, misused, tampered with, damaged by
an act of God, or subjected to abnormal working conditions.
Note
Repair or replacement, as provided under this warranty, is the exclusive remedy of the purchaser. This warranty is in lieu of all other warranties,
express or implied, including any implied warranty of merchantability or fitness for a particular use or purpose. Zyxel shall in no event be held
liable for indirect or consequential damages of any kind to the purchaser.
To obtain the services of this warranty, contact your vendor. You may also refer to the warranty policy for the region in which you bought the
device at http://www.zyxel.com/web/support_warranty_info.php.
Registration
Register your product online to receive e-mail notices of firmware upgrades and information at www.zyxel.com for global products, or at
www.us.zyxel.com for North American products.
Open Source Licenses
This product contains in part some free software distributed under GPL license terms and/or GPL like licenses. Open source licenses are provided
with the firmware package. You can download the latest firmware at www.zyxel.com. To obtain the source code covered under those Licenses,
please contact support@zyxel.com.tw to get it.
SYMBOL EXPLANATION
Alternating current (AC):
AC is an electric current in which the flow of electric charge periodically reverses direction.
Direct current (DC):
DC if the unidirectional flow or movement of electric charge carriers.
Earth; ground:
A wiring terminal intended for connection of a Protective Earthing Conductor.
Class II equipment:
The method of protection against electric shock in the case of class II equipment is either double insulation or
reinforced insulation.
Index
EMG2881-T20A User’s Guide
164
Index
A
Address Assignment 38
AP 10
AP Mode
menu 23
AP+Bridge 10
B
Bridge/Repeater 10
C
certifications 161
viewing 163
Channel 20
channel 54
Configuration
restore 103
contact information 151
copyright 157
CoS 84
CoS technologies 76
CPU usage 20
customer support 151
D
DDNS
service providers 95
DHCP 35
DHCP server
see also Dynamic Host Configuration Protocol
DHCP server 71
Differentiated Services, see DiffServ 84
DiffServ 84
marking rule 84
disclaimer 157
DNS Server 38
Domain Name System. See DNS.
DS field 84
DS, dee differentiated services
DSCP 84
DynDNS 95
DynDNS see also DDNS 95
E
encryption 55
and local (user) database 56
key 56
WPA compatible 56
ESSID 110
F
Firewall
guidelines 93
ICMP packets 95
firewall
stateful inspection 92
Firmware upload 101
file extension
using HTTP
firmware version 19
G
General wireless LAN screen 57
Guest WLAN 56
Guest WLAN Bandwidth 56
Index
EMG2881-T20A User’s Guide
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I
IGMP 39
see also Internet Group Multicast Protocol
version
IGMP version 39
Internet Group Multicast Protocol 39
IP Address 71
L
LAN 70
LAN overview 70
LAN setup 70
Language 104
Link type 20
local (user) database 55
and encryption 56
Local Area Network 70
M
MAC 64
MAC address 38, 54
cloning 38
MAC address filter 54
MAC address filtering 64
MAC filter 64
managing the device
good habits 11
using the web configurator. See web configurator.
using the WPS. See WPS.
MBSSID 10
Media access control 64
Memory usage 20
mode 10
Multicast 39
IGMP 39
N
NAT Traversal 77
Navigation Panel 21
navigation panel 21
O
operating mode 10
P
Per-Hop Behavior, see PHB 84
PHB 84
Point-to-Point Protocol over Ethernet 40
port speed 21
PPPoE 40
dial-up connection
push button 14
Q
QoS 75, 84
marking 76
setup 75
tagging 76
versus CoS 76
Quality of Service, see QoS
R
RADIUS server 55
Reset button 14
Reset the device 14
Restore configuration 103
Roaming 65
Router Mode
status screen 18
RTS/CTS Threshold 54, 65
Index
EMG2881-T20A User’s Guide
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S
Scheduling 68
Service Set 58, 63
Service Set IDentification 58, 63
Service Set IDentity. See SSID.
Single Rate Three Color Marker, see srTCM
srTCM 86
SSID 20, 54, 58, 63
stateful inspection firewall 92
Status 18
Subnet Mask 71
Summary
DHCP table 35
System General Setup 98
System restart 104
T
Time setting 100
trTCM 86
Two Rate Three Color Marker, see trTCM
U
Universal Plug and Play
Application 77
Security issues 77
user authentication 55
local (user) database 55
RADIUS server 55
V
VPN Passthrough 49
W
WAN (Wide Area Network) 37
WAN MAC address 38
warranty 163
note 163
Web Configurator
how to access 16
Overview 16
web configurator 11
WEP Encryption 61
wireless channel 110
wireless LAN 110
WPS
push button 14
wireless LAN scheduling 68
Wireless network
basic guidelines 54
channel 54
encryption 55
example 53
MAC address filter 54
overview 53
security 54
SSID 54
Wireless security 54
overview 54
type 54
wireless security 110
Wireless tutorial 24
WPA compatible 56
WPS 11
push button 14