ZyXEL Communications AMG1202-T10B Manual

AMG1202-T10B/AMG1302-T10B
Support Notes
1
All contents copyright © 2013 ZyXEL Communications Corporation.
AMG1202-T10B/AMG1302-T10B
Wireless N-Lite ADSL2+ 4-port Gateway
Support Notes
Version 1.00
Jan. 2013

AMG1202-T10B/AMG1302-T10B
Support Notes
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All contents copyright © 2013 ZyXEL Communications Corporation.
Foreward.........................................................................................................6
FAQ .................................................................................................................6
System FAQ................................................................................................6
1. How do I access the AMG1202-T10B/AMG1302-T10B Command
Line Interface (CLI)?...............................................................................6
2. How do I update the firmware and configuration file? ....................6
3. What should I do if I forget the system password?.........................6
4. How to use the Reset button?...........................................................7
5. What is SUA? When should I use SUA?...........................................7
6. Is it possible to access a server running behind SUA from the
outside Internet? How can I do it? ........................................................7
7. What IP/Port mapping does Multi-NAT support?.............................8
8. How many network users can the SUA/NAT support?....................8
9. What are Device filters and Protocol filters?....................................8
10. How can I protect against IP spoofing attacks? ............................9
Product FAQ.............................................................................................10
1. How can I manage AMG1202-T10B/AMG1302-T10B?....................10
2. What is the default password for Web Configurator?...................10
3. What’s the difference between ‘Common User Account’ and
‘Administrator Account’?.....................................................................10
4. How do I know the AMG1202-T10B/AMG1302-T10B’s WAN IP
address assigned by the ISP?.............................................................10
5. What is the micro filter or splitter used for? ..................................11
6. The AMG1202-T10B/AMG1302-T10B supports Bridge and Router
mode, what's the difference between them?......................................11
7. How do I know I am using PPPoE?.................................................11
8. Why does my provider use PPPoE? ...............................................11
9. What is DDNS?..................................................................................11
10. When do I need DDNS service?.....................................................12
11. What is DDNS wildcard? Does the
AMG1202-T10B/AMG1302-T10B support DDNS wildcard?...............12
12. What is Traffic Shaping?................................................................12
13. Why do we perform traffic shaping in the AMG1202-T10B
/AMG1302-T10B?..................................................................................13
14. What do the parameters (PCR, SCR, MBS) mean?......................13
15. What do the ATM QoS Types (CBR, UBR, VBR-nRT, VBR-RT)
mean?....................................................................................................13
16. What is content filter?....................................................................14
ADSL FAQ.................................................................................................15
1. How does ADSL compare to Cable modems? ...............................15
2. What is the expected throughput?..................................................15
3. What is the microfilter used for?.....................................................15
4. How do I know the ADSL line is up?...............................................15

AMG1202-T10B/AMG1302-T10B
Support Notes
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5. How does the AMG1302-T10B /AMG1202-T10B work on a noisy
ADSL?....................................................................................................16
6. Does the VC-based multiplexing perform better than the
LLC-based multiplexing?.....................................................................16
7. How do I know the details of my ADSL line statistics?.................16
8. What are the signaling pins of the ADSL connector? ...................16
9. What is triple play?...........................................................................16
Firewall FAQ .............................................................................................18
General ..................................................................................................18
1. What is a network firewall?...................................................18
2. What makes AMG1302-T10B /AMG1202-T10B secure?.....18
3. What are the basic types of firewalls?..................................18
4. What kind of firewall in the AMG1302-T10B/AMG1202-T10B?
.................................................................................................19
5. Why do you need a firewall when your router has packet
filtering and NAT built-in?.........................................................19
6. What is Denials of Service (DoS) attack?.............................20
7. What is Ping of Death attack? ..............................................20
8. What is Teardrop attack? .....................................................20
9. What is SYN Flood attack?...................................................20
10. What is LAND attack? ........................................................21
11 What is Brute-force attack?.................................................21
12. What is IP Spoofing attack? ...............................................21
13. What are the default ACL firewall rules in AMG1302-T10B
/AMG1202-T10B?.....................................................................21
Configuration........................................................................................22
1. How do I configure the firewall? ...........................................22
2. How do I prevent others from configuring my firewall?.........22
3. Why can't I configure my AMG1302-T10B/AMG1202-T10B
using Web Configurator/Telnet over WAN?..............................22
4. Why can't I upload the firmware and configuration file using
FTP over WAN? .......................................................................24
Log and Alert.........................................................................................24
1. When does the AMG1302-T10B/AMG1202-T10B generate the
firewall log? ..............................................................................24
2. What does the log show to us? ............................................24
3. How do I view the firewall log? .............................................25
4. When does the AMG1302-T10B/AMG1202-T10B generate the
firewall alert? ............................................................................25
5. What is the difference between the log and alert?................26
Wireless FAQ............................................................................................26
General FAQ..........................................................................................26
1. What is a Wireless LAN?......................................................26
2. What are the advantages of Wireless LAN?.........................26

AMG1202-T10B/AMG1302-T10B
Support Notes
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3. What is the disadvantage of Wireless LAN?.........................27
4. Where can you find 802.11 wireless networks? ...................27
5. What is an Access Point?.....................................................27
6. Is it possible to use wireless products from a variety of vendors?
.................................................................................................27
7. What is Wi-Fi?......................................................................28
8. What types of devices use the 2.4GHz Band? .....................28
9. Does the 802.11 interfere with Bluetooth device? ................28
10. Can radio signals pass through wall?.................................28
11. What are potential factors that may causes interference
among WLAN products? ..........................................................29
12. What's the difference between a WLAN and a WWAN?.....29
13. Can I manually swap the wireless module without damage
any hardware?..........................................................................29
14. What wireless security mode does AMG1302-T10B
/AMG1202-T10B support?........................................................30
15. What Wireless standard does AMG1302-T10B
/AMG1202-T10B support?........................................................30
16. Does AMG1302-T10B/AMG1202-T10B support MAC filtering?
.................................................................................................30
17. Does AMG1302-T10B/AMG1202-T10B support auto rate
adaption?..................................................................................30
Advanced FAQ..........................................................................................31
1. What is Ad Hoc mode?.........................................................31
2. What is Infrastructure mode? ...............................................31
3. How many Access Points are required in a given area? ......31
4. What is Direct-Sequence Spread Spectrum Technology –
(DSSS)?...................................................................................31
5. What is Frequency-hopping Spread Spectrum Technology –
(FHSS)? ...................................................................................32
6. Do I need the same kind of antenna on both sides of a link?32
7. Why the 2.4 GHZ Frequency range?....................................32
8. What is Server Set ID (SSID)? .............................................32
9. What is an ESSID?...............................................................33
Security FAQ.............................................................................................34
1. How do I secure the data across the AMG1302-T10B
/AMG1202-T10B Access Point's radio link?.............................34
2. What is WEP? ......................................................................34
3. What is WPA-PSK?..............................................................34
4. What is the difference between 40-bit and 64-bit WEP? ......34
5. What is a WEP key?.............................................................35
6. Will 128-bit WEP communicate with 64-bit WEP?................35
7. Can the SSID be encrypted?................................................35

AMG1202-T10B/AMG1302-T10B
Support Notes
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8. by turning off the broadcast of SSID, can someone still sniff
the SSID?.................................................................................35
9. What are Insertion Attacks? .................................................36
10. What is Wireless Sniffer? ...................................................36
Application Notes ........................................................................................37
General Application Notes.......................................................................37
1. Internet Access Using AMG1302-T10B/AMG1202-T10B under
Bridge mode.............................................................................37
2. Internet Access Using AMG1302-T10B/AMG1202-T10B under
Routing mode...........................................................................40
3. Setup the AMG1302-T10B/AMG1202-T10B as a DHCP Relay
.................................................................................................43
4. SUA Notes............................................................................43
5. Using the Dynamic DNS (DDNS) .........................................53
6. QoS (802.1Q).......................................................................54
7. Network Management Using SNMP.....................................55
8. Using syslog.........................................................................58
9. Using IP Alias.......................................................................58
10. Using Call Scheduling ........................................................60
11. Using IP Multicast...............................................................61
Wireless Application Notes.....................................................................63
1. Configure a Wireless Client to Ad hoc mode........................63
2. MAC Filter ............................................................................69
3. Site Survey...........................................................................71
4. Configure 802.1x and WPA..................................................74
5. WPS/WLAN Button...............................................................78
Support Tool.................................................................................................79
1. Capture the detailed logs by Hyper Terminal ....................................79
CI Command Reference ..............................................................................82
Command Syntax and General User Interface.......................................82

AMG1202-T10B/AMG1302-T10B
Support Notes
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All contents copyright © 2013 ZyXEL Communications Corporation.
Foreward
This support note content covers the AMG1202-T10B/AMG1302-T10B In the
following example, the print screen of diagrams are AMG1202-T10B
FAQ
System FAQ
1. How do I access the AMG1202-T10B/AMG1302-T10B Command Line
Interface (CLI)?
The Command Line Interface is for the Administrator use only, and it could be
accessed via telnet session.
Note: It is protected by super password, ‘1234’ by factory default.
2. How do I update the firmware and configuration file?
You can do this via accessing web GUI of AMG1202-T10B/AMG1302-T10B as
Administrator. Firmware update function is under Maintanance -> Firmware
Upgrade. Configuration update function is under Maintanance ->
Backup/Restore.
3. What should I do if I forget the system password?
In case you forget the system password, you can erase the current
configuration and restore factory defaults this way:

AMG1202-T10B/AMG1302-T10B
Support Notes
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Use the RESET button on the rear panel of AMG1202-T10B/AMG1302-T10B
to reset the router. After the router is reset, the LAN IP address will be reset to
'192.168.1.1', the common user password will be reset to '1234', and the
Administrator password will be reset to ‘1234’.
4. How to use the Reset button?
a. Turn your AMG1202-T10B/AMG1302-T10Bon. Make sure the POWER
led is on (not blinking)
b. Press the RESET button for longer than one second and shorter than
five seconds and release it.
c. Press the RESET button for six seconds and then release it. If the
POWER LED begins to blink, the default configuration has been
restored and the AMG1202-T10B/AMG1302-T10B restarts.
5. What is SUA? When should I use SUA?
SUA (Single User Account) is a unique feature supported by Prestige router
which allows multiple people to access Internet concurrently for the cost of a
single user account.
When Prestige acting as SUA receives a packet from a local client destined for
the outside Internet, it replaces the source address in the IP packet header
with its own address and the source port in the TCP or UDP header with
another value chosen out of a local pool. It then recomputed the appropriate
header checksums and forwards the packet to the Internet as if it is originated
from Prestige using the IP address assigned by ISP. When reply packets from
the external Internet are received by Prestige, the original IP source address
and TCP/UDP source port numbers are written into the destination fields of the
packet (since it is now moving in the opposite direction), the checksums are
recomputed, and the packet is delivered to its true destination. This is because
SUA keeps a table of the IP addresses and port numbers of the local systems
currently using it.
6. Is it possible to access a server running behind SUA from the outside
Internet? How can I do it?
Yes, it is possible because AMG1202-T10B/AMG1302-T10B delivers the
packet to the local server by looking up to a SUA server table. Therefore, to
make a local server accessible to the outside users, the port number and the
inside IP address of the server must be configured. (You can configure it in
Web Configurator, Advanced Setup, Network Setting-> NAT -> Port
Forwarding).

AMG1202-T10B/AMG1302-T10B
Support Notes
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7. What IP/Port mapping does Multi-NAT support?
Multi-NAT supports five types of IP/port mapping: One to One, Many to One,
Many to Many Overload, Many to Many No Overload and Server. The details
of the mapping between ILA and IGA are described as below. Here we define
the local IP addresses as the Internal Local Addresses (ILA) and the global IP
addresses as the Inside Global Address (IGA),
One to One: In One-to-One mode, the
AMG1202-T10B/AMG1302-T10B maps one ILA to one IGA.
Many to One: In Many-to-One mode, the
AMG1202-T10B/AMG1302-T10B maps multiple ILA to one IGA. This is
equivalent to SUA (i.e., PAT, port address translation), ZyXEL's Single
User Account feature (the SUA is optional in today's Prestige routers).
Many to Many Overload: In Many-to-Many Overload mode, the
AMG1202-T10B/AMG1302-T10B maps the multiple ILA to shared IGA.
Many One-to-One: In Many One-to-One mode, the
AMG1202-T10B/AMG1302-T10B maps each ILA to unique IGA.
Server: In Server mode, the AMG1202-T10B/AMG1302-T10B maps
multiple inside servers to one global IP address. This allows us to
specify multiple servers of different types behind the NAT for outside
access. Note; if you want to map each server to one unique IGA please
use the One-to-One mode.
The following table summarizes the five types.
8. How many network users can
the SUA/NAT support?
The Prestige does not limit the number
of the users but the number of the
sessions. The
AMG1202-T10B/AMG1302-T10B
supports 8192 sessions.
9. What are Device filters and
Protocol filters?
The filters have been separated into
two groups. One group is called
'device filter group', and the other is
called 'protocol filter group'. Generic
filters belong to the 'device filter group',
TCP/IP and IPX filters belong to the
NAT Type
IP Mapping
One-to-One
ILA1<--->IGA1
Many-to-One
(SUA/PAT)
ILA1<--->IGA1
ILA2<--->IGA1
...
Many-to-Many
Overload
ILA1<--->IGA1
ILA2<--->IGA2
ILA3<--->IGA1
ILA4<--->IGA2
...
Many
One-to-One
ILA1<--->IGA1
ILA2<--->IGA2
ILA3<--->IGA3
ILA4<--->IGA4
...
Server
Server 1 IP<--->IGA1
Server 2 IP<--->IGA1

AMG1202-T10B/AMG1302-T10B
Support Notes
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'protocol filter group'. You can configure the filter rule in CLI.
10. How can I protect against IP spoofing attacks?
The AMG1202-T10B/AMG1302-T10B’s filter sets provide a means to protect
against IP spoofing attacks. The basic scheme is as follows:
For the input data filter:
Deny packets from the outside that claim to be from the inside
Allow everything that is not spoofing us
Filter rule setup:
Filter type =TCP/IP Filter Rule
Active =Yes
Source IP Addr =a.b.c.d
Source IP Mask =w.x.y.z
Action Matched =Drop
Action Not Matched =Forward
Where a.b.c.d is an IP address on your local network and w.x.y.z is your
netmask:
For the output data filters:
Deny bounce back packet
Allow packets that originate from us
Filter rule setup:
Filter Type =TCP/IP Filter Rule
Active =Yes
Destination IP Addr =a.b.c.d
Destination IP Mask =w.x.y.z
Action Matched =Drop
Action Not Matched =Forward
Where a.b.c.d is an IP address on your local network and w.x.y.z is your
netmask.

AMG1202-T10B/AMG1302-T10B
Support Notes
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Product FAQ
1. How can I manage AMG1202-T10B/AMG1302-T10B?
Multilingual Embedded Web GUI for Local and Remote management
CLI (Command-line interface)
Telnet support (Administrator Password Protected ) for remote
configuration change and status monitoring
2. What is the default password for Web Configurator?
There are two different accounts for AMG1202-T10B/AMG1302-T10B Web
Configurator: Common User Account and Administrator Account.
By factory default the password for the two accounts are:
Common User Account: 1234
Administrator Account: 1234.
You can change the password after you logging in the Web Configurator.
Please record your new password whenever you change it. The system
will lock you out if you have forgotten your password.
3. What’s the difference between ‘Common User Account’and
‘Administrator Account’?
For Common User Account, it can only access the status monitor of
AMG1202-T10B/AMG1302-T10B and check the current system status.
For Administrator Account, besides accessing the status monitor of
AMG1202-T10B/AMG1302-T10B, it can also access Wizard setup/ Advanced
setup of AMG1202-T10B/AMG1302-T10B:
Moreover, only with Administrator Password, you could manage the
AMG1202-T10B/AMG1302-T10B via FTP/TFTP or Telnet.
4. How do I know the AMG1202-T10B/AMG1302-T10B’s WAN IP
address assigned by the ISP?
You can view "My WAN IP <from ISP> : x.x.x.x" shown in Web Configurator
‘Status->Device Information ->WAN Information’ to check this IP address.

AMG1202-T10B/AMG1302-T10B
Support Notes
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5. What is the micro filter or splitter used for?
Generally, the voice band uses the lower frequency ranging from 0 to 4 KHz,
while ADSL data transmission uses the higher frequency. The micro filter acts
as a low-pass filter for your telephone set to ensure that ADSL transmissions
do not interfere with your voice transmissions. For the details about how to
connect the micro filter please refer to the user's manual.
6. The AMG1202-T10B/AMG1302-T10B supports Bridge and Router
mode, what's the difference between them?
When the ISP limits some specific computers to access Internet, that means
only the traffic to/from these computers will be forwarded and the other will be
filtered. In this case, we use bridge mode which works as an ADSL modem to
connect to the ISP. The ISP will generally give one Internet account and limit
only one computer to access the Internet.
For most Internet users having multiple computers want to share an Internet
account for Internet access, they have to add another Internet sharing device,
like a router. In this case, we use the router mode which works as a general
Router plus an ADSL Modem.
7. How do I know I am using PPPoE?
PPPoE requires a user account to login to the provider's server. If you need to
configure a user name and password on your computer to connect to the ISP
you are probably using PPPoE. If you are simply connected to the Internet
when you turn on your computer, you probably are not. You can also check
your ISP or the information sheet given by the ISP. Please choose PPPoE as
the encapsulation type in the AMG1202-T10B/AMG1302-T10B if the ISP uses
PPPoE.
8. Why does my provider use PPPoE?
PPPoE emulates a familiar Dial-Up connection. It allows your ISP to provide
services using their existing network configuration over the broadband
connections. Besides, PPPoE supports a broad range of existing applications
and service including authentication, accounting, secure access and
configuration management.
9. What is DDNS?
The Dynamic DNS service allows you to alias a dynamic IP address to a static
hostname, allowing your computer to be more easily accessed from various

AMG1202-T10B/AMG1302-T10B
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locations on the Internet. To use the service, you must first apply an account
from several free Web servers such as http://www.dyndns.org/.
Without DDNS, we always tell the users to use the WAN IP of the
AMG1202-T10B/AMG1302-T10B to reach our internal server. It is
inconvenient for the users if this IP is dynamic. With DDNS supported by the
AMG1202-T10B/AMG1302-T10B, you apply a DNS name (e.g.,
www.zyxel.com.tw) for your server (e.g., Web server) from a DDNS server.
The outside users can always access the web server using the
www.zyxel.com.tw regardless of the WAN IP of the
AMG1202-T10B/AMG1302-T10B.
When the ISP assigns the AMG1202-T10B/AMG1302-T10B a new IP, the
AMG1202-T10B/AMG1302-T10B updates this IP to DDNS server so that the
server can update its IP-to-DNS entry. Once the IP-to-DNS table in the DDNS
server is updated, the DNS name for your web server (i.e., www.zyxel.com.tw)
is still usable.
10. When do I need DDNS service?
When you want your internal server to be accessed by using DNS name rather
than using the dynamic IP address, we can use the DDNS service. The DDNS
server allows to alias a dynamic IP address to a static hostname. Whenever
the ISP assigns you a new IP, the AMG1202-T10B/AMG1302-T10B sends this
IP to the DDNS server for its updates.
11. What is DDNS wildcard? Does the
AMG1202-T10B/AMG1302-T10B support DDNS wildcard?
Some DDNS servers support the wildcard feature which allows the hostname,
*.yourhost.dyndns.org, to be aliased to the same IP address as
yourhost.dyndns.org. This feature is useful when there are multiple servers
inside and you want users to be able to use things such as
www.yourhost.dyndns.org and still reach your hostname.
Yes, the AMG1202-T10B/AMG1302-T10B supports DDNS wildcard that
http://www.dyndns.org/ supports. When using wildcard, you simply enter
yourhost.dyndns.org in the Host field in Menu 1.1 Configure Dynamic DNS.
12. What is Traffic Shaping?
Traffic Shaping allocates the bandwidth to WAN dynamically and aims at
boosting the efficiency of the bandwidth. If there are several VCs in the
AMG1202-T10B/AMG1302-T10B but only one VC activated at one time, the
AMG1202-T10B/AMG1302-T10B allocates all the Bandwidth to the VC and

AMG1202-T10B/AMG1302-T10B
Support Notes
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the VC gets full bandwidth. If another VCs are activated later, the bandwidth is
yield to other VCs afterward.
13. Why do we perform traffic shaping in the AMG1202-T10B
/AMG1302-T10B?
The AMG1202-T10B/AMG1302-T10B must manage traffic fairly and provide
bandwidth allocation for different sorts of applications, such as voice, video,
and data. All applications have their own natural bit rate. Large data
transactions have a fluctuating natural bit rate. The AMG1302-T10B
/AMG1202-T10B is able to support variable traffic among different virtual
connections. Certain traffic may be discarded if the virtual connection
experiences congestion. Traffic shaping defines a set of actions taken by the
AMG1302-T10B/AMG1202-T10B to avoid congestion; traffic shaping takes
measures to adapt to unpredictable fluctuations in traffic flows and other
problems among virtual connections.
14. What do the parameters (PCR, SCR, MBS) mean?
Traffic shaping parameters (PCR, SCR, MBS) can be set in Web Configurator.
Peak Cell Rate (PCR): The maximum bandwidth allocated to this connection.
The VC connection throughput is limited by PCR.
Sustainable Cell Rate (SCR): The least guaranteed bandwidth of a VC.
When there are multi-VCs on the same line, the VC throughput is guaranteed
by SCR.
Maximum Burst Size (MBS): The amount of cells transmitted through this
VC at the Peak Cell Rate before yielding to other VCs. Total bandwidth of the
line is dedicated to single VC if there is only one VC on the line. However, as
the other VC asking the bandwidth, the MBS defines the maximum number of
cells transmitted via this VC with Peak Cell rate before yielding to other VCs.
The AMG1302-T10B /AMG1202-T10B holds the parameters for shaping the
traffic among its virtual channels. If you do not need traffic shaping, please set
SCR = 0, MBS = 0 and PCR as the maximum value according to the line rate
(for example, 2.3 Mbps line rate will result PCR as 5424 cell/sec.)
15. What do the ATM QoS Types (CBR, UBR, VBR-nRT, VBR-RT)
mean?
Constant bit rate (CBR): An ATM bandwidth-allocation service that requires
the user to determine a fixed bandwidth requirement at the time the connection
is set up so that the data can be sent in a steady stream. CBR service is often
used when transmitting fixed-rate uncompressed video.

AMG1202-T10B/AMG1302-T10B
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Unspecified bit rate (UBR): An ATM bandwidth-allocation service that does
not guarantee any throughput levels and uses only available bandwidth. UBR
is often used when transmitting data that can tolerate delays, such as e-mail.
Variable bit rate (VBR): An ATM bandwidth-allocation service that allows
users to specify a throughput capacity (i.e., a peak rate) and a sustained rate
but data is not sent evenly. You can select VBR for burst traffic and bandwidth
sharing with other applications. It contains two subclasses:
Variable bit rate nonreal time (VBR-nRT):
Variable bit rate real time (VBR-RT):
16. What is content filter?
Internet Content filter allows you to create and enforce Internet access policies
tailored to your needs. Content filter gives you the ability to block web sites that
contain key words (that you specify) in the URL. You can set a schedule for
when the AMG1302-T10B /AMG1202-T10B performs content filtering. You
can also specify trusted IP Addresses on LAN for which the AMG1302-T10B
/AMG1202-T10B will not perform content filtering. You can configure the
details about it in Web Configurator, Advanced setup, Security -> Filter.

AMG1202-T10B/AMG1302-T10B
Support Notes
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ADSL FAQ
1. How does ADSL compare to Cable modems?
ADSL provides a dedicated service over a single telephone line; cable
modems offer a dedicated service over a shared media. While cable modems
have greater downstream bandwidth capabilities (up to 24 Mbps), that
bandwidth is shared among all users on a line, and will therefore vary, perhaps
dramatically, as more users in a neighborhood get online at the same time.
Cable modem upstream traffic will in many cases be slower than ADSL, either
because the particular cable modem is inherently slower, or because of rate
reductions caused by contention for upstream bandwidth slots. The big
difference between ADSL and cable modems, however, is the number of lines
available to each. There are no more than 12 million homes passed today that
can support two-way cable modem transmissions, and while the figure also
grows steadily, it will not catch up with telephone lines for many years.
Additionally, many of the older cable networks are not capable of offering a
return channel; consequently, such networks will need significant upgrading
before they can offer high bandwidth services.
2. What is the expected throughput?
In our test, we can get about 1.6Mbps data rate on 15Kft using the 26AWG
loop. The shorter the loop, the better the throughput is.
3. What is the microfilter used for?
Generally, the voice band uses the lower frequency ranging from 0 to 4 KHz,
while ADSL data transmission uses the higher frequency. The micro filter acts
as a low-pass filter for your telephone set to ensure that ADSL transmissions
do not interfere with your voice transmissions. For the details about how to
connect the micro filter please refer to the user's manual.
4. How do I know the ADSL line is up?
You can see the DSL LED Green on the AMG1302-T10B /AMG1202-T10B’s
front panel is on when the ADSL physical layer is up.

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5. How does the AMG1302-T10B /AMG1202-T10B work on a noisy
ADSL?
Depending on the line quality, the AMG1302-T10B /AMG1202-T10B uses "Fall
Back" and "Fall Forward" to automatically adjust the date rate.
6. Does the VC-based multiplexing perform better than the
LLC-based multiplexing?
Though the LLC-based multiplexing can carry multiple protocols over a single
VC, it requires extra header information to identify the protocol being carried
on the virtual circuit (VC). The VC-based multiplexing needs a separate VC for
carrying each protocol but it does not need the extra headers. Therefore, the
VC-based multiplexing is more efficient.
7. How do I know the details of my ADSL line statistics?
You can do it in Web Configurator, Advanced Setup,
Maintenance -> Diagnostic -> DSL Line -> DSL
Status:
8. What are the signaling pins of the ADSL connector?
The signaling pins on the AMG1302-T10B /AMG1202-T10B’s ADSL connector
are pin 3 and pin 4. The middle two pins for a RJ11 cable.
9. What is triple play?
More and more Telco/ISPs are providing three kinds of services (VoIP, Video
and Internet) over one existing ADSL connection.

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The different services (such as video, VoIP and Internet access) require
different Quality of Service.
The high priority is Voice (VoIP) data.
The Medium priority is Video (IPTV) data.
The low priority is internet access such as ftp etc …
Triple Play is a port-based policy to forward packets from different LAN port to
different PVCs, thus you can configure each PVC separately to assign different
QoS to different application.

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Firewall FAQ
General
1. What is a network firewall?
A firewall is a system or a group of systems that enforces an access-control
policy between two networks. It may also be defined as a mechanism used to
protect a trusted network from an untrusted network. The firewall can be
thought of two mechanisms: One to block the traffic, and the other to permit
traffic.
2. What makes AMG1302-T10B /AMG1202-T10B secure?
The AMG1302-T10B/AMG1202-T10B is pre-configured to automatically detect
and thwart Denial of Service (DoS) attacks such as Ping of Death, SYN Flood,
LAND attack, IP Spoofing, etc. It also uses stateful packet inspection to
determine if an inbound connection is allowed through the firewall to the
private LAN. The AMG1302-T10B /AMG1202-T10B supports Network Address
Translation (NAT), which translates the private local addresses to one or
multiple public addresses. This adds a level of security since the clients on the
private LAN are invisible to the Internet.
3. What are the basic types of firewalls?
Conceptually, there are three types of firewalls:
1. Packet Filtering Firewall
2. Application-level Firewall
3. Stateful Inspection Firewall
Packet Filtering Firewalls generally make their decisions based on the header
information in individual packets. These headers information include the
source, destination addresses and ports of the packets.
Application-level Firewalls generally are hosts running proxy servers, which
permit no traffic directly between networks, and which perform logging and
auditing of traffic passing through them. A proxy server is an application
gateway or circuit-level gateway that runs on top of general operating system
such as UNIX or Windows NT. It hides valuable data by requiring users to

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communicate with secure systems by mean of a proxy. A key drawback of this
device is performance.
Stateful Inspection Firewalls restrict access by screening data packets against
defined access rules. They make access control decisions based on IP
address and protocol. They also 'inspect' the session data to assure the
integrity of the connection and to adapt to dynamic protocols. The flexible
nature of Stateful Inspection firewalls generally provides the best speed and
transparency, however, they may lack the granular application level access
control or caching that some proxies support.
4. What kind of firewall in the AMG1302-T10B/AMG1202-T10B?
1. The AMG1302-T10B/AMG1202-T10B’s firewall inspects packets
contents and IP headers. It is applicable to all protocols that understand
data in the packet is intended for other layers, from network layer up to
the application layer.
2. The AMG1302-T10B/AMG1202-T10B’s firewall performs stateful
inspection. It takes into account the state of connections it handles so
that, for example, a legitimate incoming packet can be matched with the
outbound request for that packet and allowed in. Conversely, an
incoming packet masquerading as a response to a nonexistent
outbound request can be blocked.
3. The AMG1302-T10B/AMG1202-T10B’s firewall uses session filtering,
i.e., smart rules, that enhance the filtering process and control the
network session rather than control individual packets in a session.
4. The AMG1302-T10B/AMG1202-T10B’s firewall is fast. It uses a
hashing function to search the matched session cache instead of going
through every individual rule for a packet.
5. The AMG1302-T10B/AMG1202-T10B’s firewall provides email service
to notify you for routine reports and when alerts occur.
5. Why do you need a firewall when your router has packet
filtering and NAT built-in?
With the spectacular growth of the Internet and online access, companies that
do business on the Internet face greater security threats. Although packet filter
and NAT restrict access to particular computers and networks, however, for
the other companies this security may be insufficient, because packets filters
typically cannot maintain session state. Thus, for greater security, a firewall is
considered.

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6. What is Denials of Service (DoS) attack?
Denial of Service (DoS) attacks is aimed at devices and networks with a
connection to the Internet. Their goal is not to steal information, but to disable
a device or network so users no longer have access to network resources.
There are four types of DoS attacks:
1. Those that exploits bugs in a TCP/IP implementation such as Ping of
Death and Teardrop.
2. Those that exploits weaknesses in the TCP/IP specification such as
SYN Flood and LAND Attacks.
3. Brute-force attacks that flood a network with useless data such as
Smurf attack.
4. IP Spoofing
7. What is Ping of Death attack?
Ping of Death uses a 'PING' utility to create an IP packet that exceeds the
maximum 65535 bytes of data allowed by the IP specification. The oversize
packet is then sent to an unsuspecting system. Systems may crash, hang, or
reboot.
8. What is Teardrop attack?
Teardrop attack exploits weakness in the reassemble of the IP packet
fragments. As data is transmitted through a network, IP packets are often
broken up into smaller chunks. Each fragment looks like the original packet
except that it contains an offset field. The Teardrop program creates a series of
IP fragments with overlapping offset fields. When these fragments are
reassembled at the destination, some systems will crash, hang, or reboot.
9. What is SYN Flood attack?
SYN attack floods a targeted system with a series of SYN packets. Each
packet causes the targeted system to issue a SYN-ACK response, while the
targeted system waits for the ACK that follows the SYN-ACK; it queues up all
outstanding SYN-ACK responses on what is known as a backlog queue.
SYN-ACKs are moved off the queue only when an ACK comes back or when
an internal timer (which is set a relatively long intervals) terminates the TCP