ZyXEL Communications P-791R V2 Manual

P-791R v2 Support Notes
P-791R v2
G.SHDSL.bis Router
Support Notes
Version 3.40
04/2007
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All contents copyright © 2007 ZyXEL Communications Corporation.

P-791R v2 Support Notes
FAQ.................................................................................................................5
ZyNOS FAQ.................................................................................................5
1. What is ZyNOS?..........................................................................5
2. How do I access the P-791R v2 SMT menu?.............................5
3. How do I upload the ZyNOS firmware code via console? .......5
4. How do I upgrade/backup the ZyNOS firmware by using TFTP
client program via LAN?............................................................5
5. How do I upload ROMFILE via console port?...........................6
6. How do I restore P-791R v2 configurations by using TFTP
client program via LAN?............................................................6
7. What should I do if I forget the system password? .................6
8. How to use the Reset button?....................................................6
9. What is SUA? When should I use SUA? ...................................7
10. What is the difference between SUA and Full Feature NAT?..7
11. Is it possible to access a server running behind SUA from the
outside Internet? If possible, how?..........................................8
12. When do I need to select Full Feature NAT? ............................8
13. What IP/Port mapping does Multi-NAT support?.....................9
14. How many network users can the SUA/NAT support?..........10
15. What are Device filters and Protocol filters?..........................10
16. How can I protect against IP spoofing attacks?.....................10
Product FAQ.............................................................................................12
1. What is SHDSL, SHDSL.bis?....................................................12
2. How can I manage P-791R v2?.................................................12
3. What is the default password for Web Configurator? ...........12
4. What’s the difference between ‘Common User Account’ and
‘Administrator Account’?........................................................12
5. How do I know the P-791R v2's WAN IP address assigned by
the ISP?.....................................................................................13
6. What do I need before using the SHDSL?...............................13
7. What should I do when the power LED is off? .......................13
8. How to debug while DSL LED is off? ......................................14
9. How do I verify my PC's IP address assigned by the P-791R
v2？ ......................................................................................14
10. What is Traffic Shaping?..........................................................14
11. What do the parameters (PCR, SCR, MBS) mean? ................14
12. What do ATM QoS Types (CBR, UBR, VBR-nRT, VBR-RT)
mean? ........................................................................................15
13. Why do we perform traffic shaping in the P-791R v2? ..........15
14. The P-791R v2 supports Bridge and Router mode, what's the
difference between them?.......................................................15
15. How do I know I am using PPPoE? .........................................16
16. Why does my provider use PPPoE?........................................16
17. What is DDNS?..........................................................................16
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P-791R v2 Support Notes
18. When do I need DDNS service?...............................................16
19. What is DDNS wildcard? Does the P-791R v2 support DDNS
wildcard? ..................................................................................17
20. Can the P-791R v2's SUA handle IPSec packets sent by the
IPSec gateway? ........................................................................17
21. How do I setup my P-791R v2 for routing IPSec packets over
SUA? .........................................................................................17
22. What is Traffic Redirect?..........................................................18
23. What is Dial Backup?................................................................18
DSL FAQ ...................................................................................................19
1. How does DSL compare to Cable modems?..........................19
2. How do I know the DSL line is up?..........................................19
3. How does the P-791R v2 work on a noisy DSL? ....................19
4. Does the VC-based multiplexing perform better than the
LLC-based multiplexing? ........................................................19
5. How do I know the details of my DSL line statistics?............19
6. What are the signaling pins of the DSL connector? ..............20
Application Notes ........................................................................................21
General Application Notes ......................................................................21
1. Internet Access Using P-791R v2 under Bridge mode...........21
2. Internet Access Using P-791R v2 under Routing mode ........23
3. Internet Access scenarios........................................................26
4. Point-to-point scenarios...........................................................27
5. What is the checklist for making a point-to-point connection
over P-791R v2? .......................................................................27
6. Setup the P-791R v2 as a DHCP Relay....................................28
7. SUA Notes..................................................................................29
8. Using Full Feature NAT ............................................................38
9. Using the Dynamic DNS (DDNS)..............................................46
10. Network Management Using SNMP.........................................48
11. Using syslog..............................................................................51
12. Using IP Alias............................................................................51
13. Using IP Policy Routing............................................................54
14. Using Call Scheduling ..............................................................56
15. Using IP Multicast.....................................................................58
16. How to configure packet filter on P-791R v2?........................59
17. How to setup traffic redirect in P-791R v2?............................59
18. How to deal with Triangle toute and Traffic redirect?............62
19. How to setup Dial Backup?......................................................63
Support Tool.................................................................................................65
1. LAN/WAN Packet Trace............................................................65
2. Firmware/Configurations Uploading and Downloading using
TFTP..........................................................................................70
3. Firmware/Configurations Uploading and Downloading using
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All contents copyright © 2007 ZyXEL Communications Corporation.

P-791R v2 Support Notes
FTP ............................................................................................73
CI Command Reference ..............................................................................76
Reference .....................................................................................................77
1. PPP Numbers ............................................................................77
2. Port Numbers ............................................................................90
3. Protocol Numbers.....................................................................95
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All contents copyright © 2007 ZyXEL Communications Corporation.

P-791R v2 Support Notes
FAQ
ZyNOS FAQ
1. What is ZyNOS?
ZyNOS is ZyXEL's proprietary Network Operating System. It is the platform on
all P-791R v2 routers that delivers network services and applications. It is
designed in a modular fashion so it is easy for developers to add new features.
New ZyNOS software upgrades can be easily downloaded from our FTP sites
as they become available.
2. How do I access the P-791R v2 SMT menu?
The SMT interface is a menu driven interface, which can be accessed via a
console or a Telnet connection. To access the P-791R v2 via SMT console
port, a computer equipped with communication software such as
HyperTerminal must be configured to the following parameters.
zVT100 terminal emulation
z9600bps baud rate
zN81 data format (No Parity, 8 data bits, 1 stop bit)
The default console port baud rate is 9600bps, you can change it to
115200bps in Menu 24.2.2 to speed up access of the SMT.
3. How do I upload the ZyNOS firmware code via console?
The procedure for uploading via console is as follows.
(1) Enter debug mode when powering on the P-791R v2 using a terminal
emulator
(2) Enter 'ATUR' to start the uploading
(3) Use X-modem protocol to transfer the ZyNOS code
(4) Enter 'ATGO' to restart the P-791R v2
4. How do I upgrade/backup the ZyNOS firmware by using TFTP client
program via LAN?
The P-791R v2 allows you to transfer the firmware from/to P-791R v2 by using
TFTP program via LAN. The procedure for uploading via TFTP is as follows.
(1) Use the TELNET client program in your PC to login to your P-791R v2,
and use Menu 24.8 to enter CI command 'sys stdio 0' to disable
console idle timeout
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P-791R v2 Support Notes
(2) To upgrade firmware, use TFTP client program to put firmware in file
'ras' in the P-791R v2. After data transfer is finished, the P-791R v2 will
program the upgraded firmware into FLASH ROM and reboot itself.
(3) To backup your firmware, use the TFTP client program to get file 'ras'
from the P-791R v2.
5. How do I upload ROMFILE via console port?
In some situations, you may need to upload the ROMFILE, such as losing the
system password, or the need of resetting SMT to factory default.
The procedure for uploading via the console port is as follows.
Enter debug mode when powering on the P-791R v2 using a terminal emulator
Enter 'ATLC' to start the uploading
Use X-modem protocol to transfer ROMFILE
Enter 'ATGO' to restart the P-791R v2
6. How do I restore P-791R v2 configurations by using TFTP client
program via LAN?
(1) Use the TELNET client program in your PC to login to your P-791R v2.
(2) Enter CI command 'sys stdio 0' disable Stdio idle timeout
(3) To backup the P-791R v2 configurations, use TFTP client program to
get file 'rom-0' from the P-791R v2.
(4) To restore the P-791R v2 configurations, use the TFTP client program
to put your configuration in file rom-0 in the P-791R v2.
7. 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:
Use the RESET button on the rear panel of P-791R v2 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 'user', the dministrator password will
be reset to ‘1234’.
8. How to use the Reset button?
(1) Turn your P-791R v2 on. Make sure the POWER LED is on (not
blinking)
(2) Press the RESET button for six seconds and release it. If the POWER
LED begins to blink, the default configuration has been restored and
the P-791R v2 restarts.
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All contents copyright © 2007 ZyXEL Communications Corporation.

P-791R v2 Support Notes
9. What is SUA? When should I use SUA?
SUA (Single User Account) is a unique feature supported by P-791R v2 router
which allows multiple people to access Internet concurrently for the cost of a
single user account.
When P-791R v2 acts 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 recomputes the appropriate
header checksums and forwards the packet to the Internet as if it is originated
from P-791R v2 using the IP address assigned by ISP. When reply packets
from the external Internet are received by P-791R v2, 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.
10. What is the difference between SUA and Full Feature NAT?
When you edit NAT in Web Configurator, Advanced Setup, Network -> NAT
-> General, there will be three options for you:
zInactive NAT
zSUA Only
zFull Feature
SUA (Single User Account) in previous ZyNOS versions is a NAT set with 2
rules: Many-to-One and Server. With SUA, 'visible' servers had to be mapped
to different ports, since the servers share only one global IP.
The P-791R v2 now has Full Feature NAT which supports five types of IP/Port
mapping: One to One, Many to One, Many to Many Overload, Many to Many
No Overload and Server. You can make special application when you select
Full Feature NAT. For example: With multiple global IP addresses, multiple
severs using the same port (e.g., FTP servers using port 21/20) are allowed on
the LAN for outside access.
You can edit Full Feature NAT in Network->NAT->Address Mapping
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P-791R v2 Support Notes
The P-791R v2 supports NAT sets on a remote node basis. They are reusable,
but only one set is allowed for each remote node. The P-791R v2 supports 8
sets since there are 8 remote nodes.
By fatory default, the NAT is select as SUA in Web Configurator, Advanced
Setup, Network -> NAT -> General -> NAT Setup.
11. Is it possible to access a server running behind SUA from the outside
Internet? If possible, how?
Yes, it is possible because P-791R v2 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 -> NAT -> Port Forwarding.
12. When do I need to select Full Feature NAT?
•Make multiple local servers on the LAN accessible from outside with
multiple global IP addresses
With SUA, 'visible' servers had to be mapped to different ports, since the
servers share only one global IP. But when you select Full Feature, you can
make multiple local servers (mapping the same port or not) on the LAN
accessible from outside with multiple global IP addresses.
•Support Non-NAT Friendly Applications
Some servers providing Internet applications such as some MIRC servers do
not allow users to login using the same IP address. Thus, users on the same
network can not login to the same server simultaneously. In this case it is
better to use Many-to-Many No Overload or One-to-One NAT mapping types,
thus each user login to the server using a unique global IP address.
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P-791R v2 Support Notes
13. 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 P-791R v2 maps one ILA to one
IGA.
•Many to One: In Many-to-One mode, the P-791R v2 maps multiple ILA
to one IGA. This is equivalent to SUA (i.e., PAT, port address
translation), ZyXEL's Single User Account feature that previous ZyNOS
routers supported (the SUA is optional in today's P-791R v2 routers).
•Many to Many Overload: In Many-to-Many Overload mode, the
P-791R v2 maps multiple ILA to shared IGA.
•Many One-to-One: In Many One-to-One mode, the P-791R v2 maps
each ILA to unique IGA.
•Server: In Server mode, the P-791R v2 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.
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
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P-791R v2 Support Notes
Server 2 IP<--->IGA1
14. How many network users can the SUA/NAT support?
The P-791R v2 does not limit the number of the users but the number of the
NAT sessions. The P-791R v2 supports 2048 sessions that you can use the 'ip
nat session' command in CLI to see. You can also use ‘ip nat hashTable
wanif0’ to view the current active NAT sessions.Or you can check it in below
WEB Configurator.
15. What are Device filters and Protocol filters?
In ZyNOS, 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
'protocol filter group'. You can configure the filter rule in SMT.
Note: In ZyNOS, you can not mix different filter groups in the same filter
set.
16. How can I protect against IP spoofing attacks?
The P-791R v2'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
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All contents copyright © 2007 ZyXEL Communications Corporation.