ZyXEL Communications P-661HW-D Series Installation instructions

P-661HW-D Series
802.11g Wireless ADSL2+ 4-port Security Gateway
Support Notes
Version3.40
Mar. 2006

P-661HW-D Series Support Notes
FAQ.................................................................................................................7
ZyNOS FAQ.................................................................................................7
1. What is ZyNOS?...................................................................................7
2. What’s Multilingual Embedded Web Configurator?...............................7
3. How do I access the P-661HW-D Command Line Interface (CLI)?......7
4. How do I update the firmware and configuration file?...........................7
5. How do I upgrade/backup the ZyNOS firmware by using TFTP client
program via LAN?.....................................................................................7
6. How do I restore P-661HW-D configurations by using TFTP client
program via LAN?.....................................................................................8
7. What should I do if I forget the system password? ...............................8
8. How to use the Reset button?...............................................................8
9. What is SUA? When should I use SUA? ..............................................8
10. What is the difference between SUA and Full Feature NAT?.............9
11. Is it possible to access a server running behind SUA from the outside
Internet? How can I do it?.........................................................................9
12. When do I need select Full Feature NAT?........................................10
13. What IP/Port mapping does Multi-NAT support?..............................10
14. How many network users can the SUA/NAT support? .....................11
15. What are Device filters and Protocol filters?.....................................11
16. How can I protect against IP spoofing attacks?................................11
Product FAQ...............................................................................................13
1. How can I manage P-661HW-D?........................................................13
2. What is the default password for Web Configurator?..........................13
3. What’s the difference between ‘Common User Account’ and
‘Administrator Account’?.........................................................................13
4. How do I know the P-661HW-D's WAN IP address assigned by the
ISP?........................................................................................................13
5. What is the micro filter or splitter used for?.........................................13
6. The P-661HW-D supports Bridge and Router mode, what's the
difference between them? ......................................................................14
7. How do I know I am using PPPoE?....................................................14
8. Why does my provider use PPPoE?...................................................14
9. What is DDNS?...................................................................................14
10. When do I need DDNS service?.......................................................15
11. What is DDNS wildcard? Does the P-661HW-D support DDNS
wildcard? ................................................................................................15
12. Can the P-661HW-D's SUA handle IPSec packets sent by the IPSec
gateway? ................................................................................................15
13. How do I setup my P-661HW-D for routing IPSec packets over SUA?
................................................................................................................15
14. What is Traffic Shaping?...................................................................16
15. Why do we perform traffic shaping in the P-661HW-D? ...................16
16. What do the parameters (PCR, SCR, MBS) mean?.........................17
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P-661HW-D Series Support Notes
17. What do the ATM QoS Types (CBR, UBR, VBR-nRT, VBR-RT) mean?
................................................................................................................17
18. What is content filter?.......................................................................17
ADSL FAQ .................................................................................................19
1. How does ADSL compare to Cable modems?....................................19
2. What is the expected throughput?......................................................19
3. What is the microfilter used for? .........................................................19
4. How do I know the ADSL line is up?...................................................19
5. How does the P-661HW-D work on a noisy ADSL? ...........................19
6. Does the VC-based multiplexing perform better than the LLC-based
multiplexing?...........................................................................................20
7. How do I know the details of my ADSL line statistics?........................20
8. What are the signaling pins of the ADSL connector?..........................20
9. What is triple play? .............................................................................20
Firewall FAQ .............................................................................................22
General...................................................................................................22
1. What is a network firewall?...................................................22
2. What makes P-661HW-D secure?........................................22
3. What are the basic types of firewalls?..................................22
4. What kind of firewall is the P-661HW-D?..............................23
5. Why do you need a firewall when your router has packet
filtering and NAT built-in?.........................................................23
6. What is Denials of Service (DoS) attack?.............................23
7. What is Ping of Death attack?..............................................24
8. What is Teardrop attack? .....................................................24
9. What is SYN Flood attack?...................................................24
10. What is LAND attack? ........................................................24
11 What is Brute-force attack? .................................................25
12. What is IP Spoofing attack? ...............................................25
13. What are the default ACL firewall rules in P-661HW-D? ....25
Configuration ..........................................................................................25
1. How do I configure the firewall? ...........................................25
2. How do I prevent others from configuring my firewall?.........25
3. Why can't I configure my P-661HW-D using Web
Configurator/Telnet over WAN? ...............................................26
4. Why can't I upload the firmware and configuration file using
FTP over WAN? .......................................................................27
Log and Alert ..........................................................................................28
1. When does the P-661HW-D generate the firewall log?........28
2. What does the log show to us? ............................................28
3. How do I view the firewall log? .............................................28
4. When does the P-661HW-D generate the firewall alert?......29
5. What is the difference between the log and alert?................29
VPN FAQ ...................................................................................................30
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P-661HW-D Series Support Notes
General FAQ...........................................................................................30
1. What is VPN?.......................................................................30
2. Why do I need VPN?............................................................30
3. What are most common VPN protocols?..............................30
4. What is PPTP?.....................................................................30
5. What is L2TP?......................................................................31
6. What is IPSec?.....................................................................31
7. What secure protocols does IPSec support?........................31
8. What are the differences between 'Transport mode' and
'Tunnel mode’?.........................................................................31
9. What is SA?..........................................................................32
10. What is IKE?.......................................................................32
11. What is Pre-Shared Key?...................................................32
12. What are the differences between IKE and manual key VPN?
.................................................................................................32
13. What is Phase 1 ID for?......................................................32
14. What is FQDN? ..................................................................33
15. When should I use FQDN?.................................................33
Advanced FAQ .......................................................................................33
1. How do I configure VPN?.....................................................33
2. What kind of VPN protocols are supported on P-661HW-D?
.................................................................................................34
3. What types of encryption does P-661HW-D VPN support?..34
4. What types of authentication does P-661HW-D VPN support?
.................................................................................................34
5. I am planning my P-661HW-D VPN configuration. What do I
need to know?..........................................................................34
6. Does P-661HW-D support dynamic secure gateway IP?.....35
7. What VPN gateway has been tested with P-661HW-D
successfully?............................................................................35
8. What VPN software has been tested with P-661HW-D
successfully? ...........................................................................36
11. How do I configure P-661HW-D with NAT for internal
servers?....................................................................................37
12. I am planning my P-661HW-D behind a NAT router. What do
I need to know?........................................................................37
13. How can I keep a tunnel alive?...........................................37
14. Single, Range, Subnet, which types of IP address do
P-661HW-D support in VPN/IPSec?.........................................38
15. Can P-661HW-D support VPN passthrough?.....................38
16. Can P-661HW-D behave as a NAT router supporting IPSec
passthrough and an IPSec gateway simultaneously? ..............38
Wireless FAQ............................................................................................39
General FAQ...........................................................................................39
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P-661HW-D Series Support Notes
1. What is a Wireless LAN?......................................................39
2. What are the advantages of Wireless LAN?.........................39
3. What is the disadvantage of Wireless LAN?.........................39
4. Where can you find 802.11 wireless networks?....................40
5. What is an Access Point?.....................................................40
6. What’s the difference between IEEE802.11a/b/g? ...............40
7. Is it possible to use wireless products from a variety of vendors?
.................................................................................................40
8. What is Wi-Fi?......................................................................40
9. What types of devices use the 2.4GHz Band? .....................40
10. Does the 802.11 interfere with Bluetooth device? ..............41
11. Can radio signals pass through wall?.................................41
12. What are potential factors that may causes interference
among WLAN products? ..........................................................41
13. What's the difference between a WLAN and a WWAN? ....41
14. Can I manually swap the wireless module without damage
any hardware?..........................................................................42
15. What wireless security mode does P-661HW-D support?..42
16. What Wireless standard does P-661HW-D support?..........42
17. Does P-661HW-D support MAC filtering? ..........................42
18. Does P-661HW-D support auto rate adaption?..................42
Advanced FAQ .......................................................................................42
1. What is Ad Hoc mode?.........................................................42
2. What is Infrastructure mode? ...............................................42
3. How many Access Points are required in a given area? ....42
4. What is Direct-Sequence Spread Spectrum Technology –
(DSSS)?...................................................................................43
5. What is Frequency-hopping Spread Spectrum Technology –
(FHSS)? .................................................................................43
6. Do I need the same kind of antenna on both sides of a link?
.................................................................................................43
7. Why the 2.4 GHZ Frequency range? ...................................43
8. What is Server Set ID (SSID)? ............................................43
9. What is an ESSID? ..............................................................43
Security FAQ ..........................................................................................44
1. How do I secure the data across the P-661HW-D Access
Point's radio link? .....................................................................44
2. What is WEP? ......................................................................44
3. What is WPA? ......................................................................44
4. What is the difference between 40-bit and 64-bit WEP? . ....45
5. What is a WEP key?.............................................................45
6. Will 128-bit WEP communicate with 64-bit WEP? ...............45
7. Can the SSID be encrypted?................................................45
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P-661HW-D Series Support Notes
8. By turning off the broadcast of SSID, can someone still sniff
the SSID?.................................................................................45
9. What are Insertion Attacks? .................................................45
10. What is Wireless Sniffer? ...................................................45
11. What is OTIST? How do I use it? .......................................45
Application Notes.....................................................................................47
General Application Notes......................................................................47
1. Internet Access Using P-661HW-D under Bridge mode.......47
2. Internet Access Using P-661HW-D under Routing mode.....49
3. Setup the P-661HW-D as a DHCP Relay.............................51
4. SUA Notes............................................................................52
5. Using Full Feature NAT........................................................61
6. Using the Dynamic DNS (DDNS) .........................................73
7. Network Management Using SNMP.....................................75
8. Using syslog.........................................................................78
9. Using IP Alias.......................................................................78
10. Using IP Policy Routing......................................................80
11. Using Call Scheduling ........................................................84
12. Using IP Multicast...............................................................86
13. Using Bandwidth Management...........................................87
14. Using Zero-Configuration ...................................................90
15. How could I configure triple play on P-661HW-D?..............93
16. How to configure packet filter on P-661HW-D?..................93
IPSEC VPN Application Notes................................................................97
1. How to use P-661HW-D to build VPN Tunnel with another
VPN Gateway/ Software?.........................................................97
2. How to build a VPN between Secure Gateway with Dynamic
WAN IP Address?...................................................................103
3. Configure NAT for internal servers.....................................105
4. VPN Routing between Branch Office through Headquarter106
Wireless Application Notes...................................................................111
1. Configure a Wireless Client to Ad hoc mode......................111
2. Configuring Infrastructure mode.........................................115
3. MAC Filter ..........................................................................119
4. Setup WEP (Wired Equivalent Privacy)..............................121
5. Site Survey.........................................................................126
6. Configure 802.1x and WPA................................................129
Support Tool...........................................................................................134
1. LAN/WAN Packet Trace ...................................................................134
Online Trace .......................................................................134
Offline Trace .......................................................................136
Capture the detailed logs by Hyper Terminal ......................137
2. Firmware/Configurations Uploading and Downloading using TFTP..139
•Using TFTP client software...................................................139
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P-661HW-D Series Support Notes
•Using TFTP command on Windows NT................................141
•Using TFTP command on UNIX ...........................................141
3. Using FTP to Upload the Firmware and Configuration Files.............142
CI Command Reference.........................................................................145
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P-661HW-D Series Support Notes
FAQ
ZyNOS FAQ
1. What is ZyNOS?
ZyNOS is ZyXEL's proprietary Network Operating System. It is the platform on
all Prestige 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. What’s Multilingual Embedded Web Configurator?
Multilinggual Embedded Web Configurator means that it can display with 3
kinds of languanges: English, French, and German. By factory default it
displays with English, and you can change it in Web GUI.
3. How do I access the P-661HW-D 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.
4. How do I update the firmware and configuration file?
You can do this if you access the P-661HW-D as Administrator. You can
upload the firmware and configuration file to Prestige from Web Condigurator,
or using FTP or TFTP client software. You CAN NOT upload the firmware and
configuration file via Telnet because the Telnet connection will be dropped
during uploading the firmware. Please do not power off the router right after the
FTP or TFTP uploading is finished, the router will upload the firmware to its
flash at this moment.
Note: There may be firmware that could not be upgraded from Web
Configurator. In this case, ZyXEL will prepare special Upload Software
for you. Please read the firmware release note carefully when you want to
upload a new fireware.
5. How do I upgrade/backup the ZyNOS firmware by using TFTP client
program via LAN?
The P-661HW-D allows you to transfer the firmware to P-661HW-D using
TFTP program via LAN. The procedure for uploading ZyNOS via TFTP is as
follows.
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P-661HW-D Series Support Notes
a. Use the TELNET client program in your PC to login to your P-661HW-D.
b. Enter CI command 'sys stdio 0' to disable Stdio idle timeout
c. To upgrade firmware, use TFTP client program to put firmware in file
'ras' in the Prestige. After data transfer is finished, the P-661HW-D will
program the upgraded firmware into FLASH ROM and reboot itself.
d. To backup your firmware, use the TFTP client program to get file 'ras'
from the Prestige.
6. How do I restore P-661HW-D configurations by using TFTP client
program via LAN?
a. Use the TELNET client program in your PC to login to your P-661HW-D.
b. Enter CI command 'sys stdio 0' disable Stdio idle timeout
c. To backup the P-661HW-D configurations, use TFTP client program to
get file 'rom-0' from the P-661HW-D.
d. To restore the P-661HW-D configurations, use the TFTP client program
to put your configuration in file rom-0 in the P-661HW-D.
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-661HW-D 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 Administrator password will
be reset to ‘1234’.
8. How to use the Reset button?
a. Turn your P-661HW-D on. 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. If the POWER LED begins to blink, the
P-661HW-D’s wireless auto security function-OTIST has been enabled.
c. Press the RESET button for six seconds and release it. If the POWER
LED begins to blink, the default configuration have been restored and
the P-661HW-D restarts.
9. 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.
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P-661HW-D Series Support Notes
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 recomputes 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.
10. What is the difference between SUA and Full Feature NAT?
When you edit a remote node in Web Configurator, Advanced Setup, Network
-> Remote Node -> Edit, there will be three options for you:
•None
•SUA Only
•Full 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-661HW-D 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.
The P-661HW-D supports NAT sets on a remote node basis. They are
reusable, but only one set is allowed for each remote node. The P-661HW-D
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? How can I do it?
Yes, it is possible because P-661HW-D delivers the packet to the local server
by looking up to a SUA server table. Therefore, to make a local server
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P-661HW-D Series Support Notes
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 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.
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-661HW-D maps one ILA to
one IGA.
•Many to One: In Many-to-One mode, the P-661HW-D 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 Prestige routers).
•Many to Many Overload: In Many-to-Many Overload mode, the
P-661HW-D maps the multiple ILA to shared IGA.
•Many One-to-One: In Many One-to-One mode, the P-661HW-D maps
each ILA to unique IGA.
•Server: In Server mode, the P-661HW-D 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.
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P-661HW-D Series Support Notes
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
Server 2 IP<--->IGA1
14. 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 P-661HW-D supports 1024 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.
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 CLI.
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-661HW-D'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
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P-661HW-D Series Support Notes
•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 No Matched =Forward
Where a.b.c.d is an IP address on your local network and w.x.y.z is your
netmask.
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P-661HW-D Series Support Notes
Product FAQ
1. How can I manage P-661HW-D?
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
FTP/ TFTP sever, firmware upgrade and configuration backup and
restore are supported(Administrator Password Protected)
2. What is the default password for Web Configurator?
There are two different accounts for P-661HW-D Web Configurator: Common
User Account and Administrator Account.
By factory default the password for the two accounts are:
•Common User Account: user
•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
P-661HW-D and check the current system status.
For Administrator Account, besides accessing the status monitor of
P-661HW-D, it can also access Winzard setup/ Advanced setup of
P-661HW-D:
Moreover, only with Administrator Password, you could manage the
P-661HW-D via FTP/TFTP or Telnet.
4. How do I know the P-661HW-D'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.
5. What is the micro filter or splitter used for?
Generally, the voice band uses the lower frequency ranging from 0 to 4KHz,
while ADSL data transmission uses the higher frequency. The micro filter acts
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P-661HW-D Series Support Notes
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 P-661HW-D 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 P-661HW-D 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
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 P-661HW-D
to reach our internal server. It is inconvenient for the users if this IP is dynamic.
With DDNS supported by the P-661HW-D, you apply a DNS name (e.g.,
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P-661HW-D Series Support Notes
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 P-661HW-D.
When the ISP assigns the P-661HW-D a new IP, the P-661HW-D 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 P-661HW-D sends this IP to the DDNS
server for its updates.
11. What is DDNS wildcard? Does the P-661HW-D 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 P-661HW-D 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. Can the P-661HW-D's SUA handle IPSec packets sent by the IPSec
gateway?
Yes, the P-661HW-D's SUA can handle IPSec ESP Tunneling mode. We know
when packets go through SUA, SUA will change the source IP address and
source port for the host. To pass IPSec packets, SUA must understand the
ESP packet with protocol number 50, replace the source IP address of the
IPSec gateway to the router's WAN IP address. However, SUA should not
change the source port of the UDP packets which are used for key
managements. Because the remote gateway checks this source port during
connections, the port thus is not allowed to be changed.
13. How do I setup my P-661HW-D for routing IPSec packets over SUA?
For outgoing IPSec tunnels, no extra setting is required.
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For forwarding the inbound IPSec ESP tunnel, A 'Default' server set is required.
You could configure it in Web Configurator, Advanced Setup, Network -> NAT
-> Port Forwarding -> Default Server Setup:
It is because SUA makes your LAN appear as a single machine to the outside
world. LAN users are invisible to outside users. So, to make an internal server
for outside access, we must specify the service port and the LAN IP of this
server in Web configurator. Thus SUA is able to forward the incoming packets
to the requested service behind SUA and the outside users access the server
using the P-661HW-D's WAN IP address. So, we have to configure the internal
IPsec client as a default server (unspecified service port) when it acts a server
gateway.
14. What is Traffic Shaping?
Traffic Shaping allocates the bandwidth to WAN dynamically and aims at
boosting the efficiency of the bandwidth. If there are serveral VCs in the
P-661HW-D but only one VC activated at one time, the P-661HW-D allocates
all the Bandwidth to the VC and the VC gets full bandwidth. If another VCs are
activated later, the bandwidth is yield to other VCs after ward.
15. Why do we perform traffic shaping in the P-661HW-D?
The P-661HW-D 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 P-661HW-D 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 P-661HW-D to avoid congestion; traffic shaping takes
measures to adapt to unpredictable fluctuations in traffic flows and other
problems among virtual connections.
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P-661HW-D Series Support Notes
16. What do the parameters (PCR, SCR, MBS) mean?
Traffic shaping parameters (PCR, SCR, MBS) can be set in Web Configurator,
Advanced Setup, Network -> Remote Node -> Edit -> ATM Setup:
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 P-661HW-D 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.)
17. 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.
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 bursty 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):
18. 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
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P-661HW-D Series Support Notes
when the P-661HW-D performs content filtering. You can also specify trusted
IP Addresses on LAN for which the P-661HW-D will not perform content
filtering. You can configure the details about it in Web Configurator, Advanced
setup, Security -> Content Filter.
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P-661HW-D Series Support Notes
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 30 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 4KHz,
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 P-661HW-D's front panel is on when
the ADSL physical layer is up.
5. How does the P-661HW-D work on a noisy ADSL?
Depending on the line quality, the P-661HW-D uses "Fall Back" and "Fall
Forward" to automatically adjust the date rate.
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