ZyXEL Communications P-793H V2 - Manual

P-793H v2
G.SHDSL.bis Bonded Broadband Gateway
Support Notes
Version 3.70
02/2010

P-793H v2 Support Notes
FAQ............................................................................................................................... 4
ZyNOS FAQ ...................................................... 4
1. What isZyNOS?...................................................................................4
2. How do I accessthe P-793H v2 SMT menu?....................................4
3. How do I uploadthe ZyNOS firmware code via console?............... 4
4. How do I upgrade/backup the ZyNOS firmware by using TFTP
client programvia LAN?..........................................................................4
6. How do I restore P-793Hv2 configurationsby using TFTP client
program via LAN?.................................................................................. 5
7. What should I doif I forget the system password?......................... 5
8. How to use the Reset button?.......................................................... 5
9. What isSUA? Whenshould I use SUA?........................................... 6
10. What isthe difference between SUAand FullFeature NAT?........ 6
11. Is it possible to accessa server runningbehind SUA from the
outside Internet?Ifpossible,how?....................................................... 7
12. When do I needto select Full Feature NAT?.................................. 7
13. What IP/Port mapping doesMulti-NAT support?........................... 7
14. How many network userscanthe SUA/NAT support?.................. 8
15. What are Device filtersand Protocol filters?.................................. 9
16. How can I protect against IP spoofing attacks? ............................ 9
Product FAQ .................................................... 11
1. What isSHDSL, SHDSL.bis? ........................................................... 11
2. How can I manage P-793H v2?........................................................ 11
3. What isthe default password for Web Configurator?................... 11
4. What‟s the difference between „Common User Account‟ and
„Administrator Account‟?..................................................................... 11
5. How do I know the P-793H v2's WANIP address assigned by the ISP?
................................................................................................................ 11
6. What do I need before using the SHDSL?....................................... 12
7. What should I dowhen the power(PWR) LED isoff?.................... 12
8. How to debugwhile DSL LED isoff?............................................... 12
9. How do I verify my PC'sIP addressassigned by the P-793H v2?.. 12
10. What isTraffic Shaping?................................................................. 12
11. What do the parameters(PCR, SCR, MBS) mean?....................... 12
12. What do ATM QoSTypes(CBR, UBR, VBR-nRT, VBR-RT) mean?
................................................................................................................ 13
13. Why do we performtraffic shapingin the P-793H v2?................. 13
14. The P-793H v2 supportsBridge and Router mode, what'sthe
difference betweenthem?.................................................................... 14
15. How do I know I am using PPPoE?............................................... 14
16. Why doesmy provider use PPPoE?............................................. 14
17. What isDDNS?................................................................................. 14
18. When do I needDDNS service?....................................................... 15
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P-793H v2 Support Notes
19. What is DDNS wildcard? Does the P-793H v2support DDNS wildcard?
................................................................................................................ 15
20. Can the P-793H v2'sSUA handleIPSec packetssent by the IPSec
gateway?............................................................................................... 15
21. How do I setup my P-793H v2 for routing IPSec packetsover SUA?
................................................................................................................ 15
22. What isVLAN?................................................................................ 16
23. 802.1Q/1P.......................................................................................... 16
24. What isTraffic Redirect ?................................................................ 17
25. What isDial Backup?...................................................................... 17
DSL FAQ ........................................................ 17
1. How doesDSL compare to Cable modems?................................... 17
2. How do I know the DSL line isup? .................................................. 18
3. How doesthe P-793H v2 work on a noisy DSL?............................ 18
4. Doesthe VC-based multiplexing performbetter than the LLC-based
multiplexing?.......................................................................................... 18
5. How do I know the detailsof my DSL line statistics? .................... 18
6. What are the signalingpinsof the DSLconnector?....................... 19
7. What istriple play?........................................................................... 19
Firewall FAQ .................................................... 20
General................................................................................................... 20
Configuration........................................................................................ 23
Log and Alert......................................................................................... 26
IPSec FAQ ...................................................... 28
VPN Overview ....................................................................................... 28
P-793H v2 VPN...................................................................................... 32
Application Notes.................................................................................................... 38
General Application Notes ....................................... 38
1. Internet AccessUsing P-793H v2 under Bridge mode................... 38
2. Internet AccessUsing P-793H v2 under Routingmode................. 40
3. Internet Accessscenarios................................................................ 42
4. Back to back scenarios..................................................................... 43
5. What isthe checklist for making a 1-1 Back-to-Back connection
over P-793H v2?...................................................................................... 44
6. What isthe checklist for making a 1-2 Back-to-Back connection
over P-793H v2?...................................................................................... 45
7. Setup the P-793H v2 asa DHCP Relay............................................... 45
8. SUA Notes.......................................................................................... 46
9. Using Full Feature NAT....................................................................... 55
10. Using the Dynamic DNS (DDNS) ..................................................... 63
11. Network Management Using SNMP ................................................ 65
12. Using syslog .................................................................................... 68
13. Using IP Alias.................................................................................... 68
14. Using IP Policy Routing................................................................... 71
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P-793H v2 Support Notes
15. Using Call Scheduling.................................................................... 73
16. Using IP Multicast............................................................................. 75
17. Using Bandwidth Management....................................................... 76
18. How to configure packet filteron P-793H v2?.............................. 79
19. How could I configure triple play on P-793H v2?......................... 79
20. How to setup traffic redirect in P-793H v2?.................................. 80
21. How to deal with Triangle Route and Traffic redirect?.................. 82
22. How to setup Dial Backup?............................................................ 85
IPSEC VPNApplicationNotes .................................... 86
1. How to use P-793H v2 to build VPN Tunnel withanother VPN
Gateway/ Software?.............................................................................. 86
2. How to build a VPN between Secure Gateway with Dynamic WAN
IP Address?........................................................................................... 92
3. Configure NAT for internal servers................................................. 94
4. VPNRouting between BranchOffice through Headquarter.......... 95
Support Tool .................................................... 99
1. LAN/WAN Packet Trace.................................................................... 99
2. Firmware/ConfigurationsUploadingand Downloading using TFTP
.............................................................................................................. 103
3. Using FTP to Upload the Firmware and ConfigurationFiles...... 106
CI Command Reference ......................................... 109
Reference ...................................................... 1 10
1. PPP Numbers.................................................................................. 110
2. Port Numbers.................................................................................. 122
3. Protocol Numbers........................................................................... 126
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P-793H v2 Support Notes
FAQ
ZyNOS FAQ
1. What isZyNOS?
ZyNOS is ZyXEL's proprietary Network Operating System. It is the platform on
all P-793Hv2 routers that delivers network services and applications. It is
designed ina modular fashion soit iseasy fordevelopers toadd new features.
NewZyNOS software upgrades can be easily downloaded from our FTP sites
as they become available.
2. How do I accessthe P-793Hv2 SMT menu?
The SMTinterface is a menudriveninterface, which can beaccessedvia a
RS232 console or a Telnet connection. To access the P-793Hv2 via SMT
console port, a computerequipped with communication software such as
HyperTerminal must be configuredto the following parameters.
 VT100 terminal emulation
 9600bps baud rate
 N81data format (No Parity, 8 data bits, 1stopbit)
The default consoleport baudrate is 9600bps, you canchangeit to 115200bps
inMenu 24.2.2 tospeedupaccessoftheSMT.
3. How do I uploadthe ZyNOS firmware code via console?
The procedure for uploading via console is as follows.
(1) Enterdebug mode when poweringonthe P-793H v2 using a
terminal emulator
(2) Enter'ATUR' tostart the uploading
(3) Use X-modem protocol to transfer the ZyNOS code
(4) Enter'ATGO'to restart the P-793H v2
4. How do I upgrade/backup the ZyNOS firmware by using TFTPclient
program via LAN?
The P-793H v2 allows you totransfer the firmware from/toP-793Hv2 by using
TFTP program via LAN. The procedureforuploadingvia TFTP is as follows.
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P-793H v2 Support Notes
(1) Use the TELNETclient program in your PC tologin to yourP-793Hv2,
and use Menu 24.8 toenterCI command 'sys stdio 0'to disable
console idletimeout
(2) To upgradefirmware, useTFTP client program toput firmware infile
'ras' in the P-793Hv2. Afterdata transfer is finished, the P-793H v2
will program the upgraded firmware into FLASH ROM and reboot
itself.
(3) To backupyourfirmware, use theTFTP client program to get file 'ras'
from the P-793H v2.
5. How do I uploadROMFILE via console port?
In some situations,you mayneed toupload the ROMFILE, such as losing the
system password, orthe need ofresettingSMTto factorydefault.
The procedurefor uploading via the consoleport is as follows.
(1) Enterdebug mode when poweringonthe P-793H v2 using a
terminal emulator
(2) Enter'ATLC' tostart the uploading
(3) Use X-modem protocol totransfer ROMFILE
(4) Enter'ATGO'to restart the P-793H v2
6. How do I restore P-793H v2 configurationsby using TFTP client
program via LAN?
(1) Use the TELNETclient program in your PCtologin toyourP-793Hv2.
(2) Enter CI command 'sys stdio 0' disable Stdioidle timeout
(3) To backupthe P-793Hv2 configurations, use TFTP client program to
get file 'rom-0' from the P-793Hv2.
(4) To restore theP-793Hv2 configurations, use theTFTP client program to
put your configuration infile rom-0 inthe P-793H v2.
7. What should I doif I forget the system password?
In case you forget the systempassword, you can erase the current
configuration and restore factory defaults thisway:
Use the RESET button on the rear panel of P-793Hv2 toreset the router.
After the routeris reset, the LAN IP address willbereset to'192.168.1.1', the
common user password will be resetto'user', theAdministratorpasswordwill
be reset to „1234‟.
8. How to use the Reset button?
(1) Turn your P-793Hv2 on. Make surethe POWER led is on (not blinking)
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P-793H v2 Support Notes
(2) Press the RESET buttonfor longerthan one secondandshorterthan
five seconds andrelease it.Ifthe POWER LED beginstoblink, the P-
793H v2‟s wireless auto security function-OTIST has been enabled.
(3) Press the RESET buttonfor six secondsandrelease it. Ifthe POWER
LEDbegins toblink, the default configuration has been restored and the
P-793Hv2 restarts.
9. What isSUA? Whenshould I use SUA?
SUA (Single User Account) is a unique feature supported by P-793H v2
router which allows multiple people to access Internet concurrently for the
cost ofa single useraccount.
When P-793Hv2 acts as SUAreceives a packetfrom alocal client destined
for theoutsideInternet, it replacesthesource address inthe IP packetheader
with its ownaddress and thesource port inthe TCP or UDP header with
another value chosenout ofa local pool. It then recomputes the appropriate
header checksums and forwards thepacket to the Internet as if it is originated
from P-793H v2 using the IP address assigned by ISP. When reply packets
from the external Internet are received by P-793H 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 atable of the IP addresses and port numbers of
the local systems currently using it.
10. What isthe difference betweenSUA and Full Feature NAT?
When you edit a remote node inWeb Configurator, AdvancedSetup, Network ->
Remote Node -> Edit, there will bethreeoptionsforyou:
 None
 SUA Only
 Full Feature
SUA (Single UserAccount) in previous ZyNOS versions is a NATset with 2
rules: Many-to-One and Server.With SUA, 'visible' servers had to be mapped
to different ports, since theservers share only one global IP.
The P-793H 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 thesame port (e.g., FTP servers using port
21/20) are allowed on the LAN for outside access.
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P-793H v2 Support Notes
The P-793Hv2 supports NATsetson a remote node basis. They are reusable,
but only one set is allowed for each remote node. The P-793H v2 supports 8
sets since thereare 8 remotenodes.
By factory default, theNATis select asSUA in Web Configurator, Advanced
Setup, Network -> NAT -> General -> NAT Setup.
11. Isitpossible to accessa server runningbehind SUA from the outside
Internet?Ifpossible,how?
Yes, it is possible because P-793Hv2 delivers the packet tothe local server by
looking up toa SUA server table. Therefore, to make alocal serveraccessible
tothe outside users, the port number and the inside IP address ofthe server
must beconfigured. (Youcan configureit in Web Configurator, Advanced
Setup, Network -> NAT -> Port Forwarding).
12. When do I needto selectFull FeatureNAT
?
 Make multiple localservers on theLAN accessible from outsidewith
multiple global IP addresses
With SUA, 'visible'servers had tobe mapped todifferent ports, sincethe
servers share only one global IP. But when youselect Full Feature, you can
make multiple localservers (mapping the same port or not) ontheLAN
accessible from outside with multiple global IP addresses.
 Support Non-NATFriendly Applications
Someservers providing Internet applications suchas some MIRCservers do
not allow users tologin using the same IP address. Thus, users on the same
network can not login to the same server simultaneously. In this case it is
betterto use Many-to-Many No Overload or One-to-One NATmapping types,
thus each user login tothe server using a unique global IP address.
13. What IP/Port mapping doesMulti-NAT support?
Multi-NATsupports fivetypes ofIP/port mapping:One toOne, ManytoOne,
Many toMany Overload, Many toManyNo Overload andServer. The details
of themapping betweenILA 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-793Hv2 maps one ILA to one
IGA.
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P-793H v2 Support Notes
 Many to One: InMany-to-One mode, the P-793Hv2 maps multiple ILA
toone IGA. This is equivalent toSUA (i.e., PAT, port address
translation), ZyXEL's Single UserAccount feature thatprevious ZyNOS
routers supported(the SUA is optional in today's P-793Hv2 routers).
 Many to Many Overload: In Many-to-Many Overload mode, the
P-793Hv2 maps multiple ILA toshared IGA.
 Many One-to-One: InMany One-to-Onemode, the P-793H v2 maps
each ILA tounique IGA.
 Server: In Server mode, the P-793H v2 maps multiple inside servers
to one global IP address. This allows us to specify multiple servers of
different types behind the NATfor outside access. Note,ifyou want to
map each server to one unique IGA please use the One-to-Onemode.
The following table summarizesthe 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 manynetwork userscan the SUA/NAT support?
The P-793Hv2 does not limit the number ofthe users but thenumber ofthe
NATsessions. The P-793H v2 supports 2048 sessions thatyou can use the 'ip
nat session' command inCLItosee. You can also use „ip nat hashTable
wanif0‟toview the current active NATsessions.Oryoucan checkit in below
WEB Configurator.
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P-793H v2 Support Notes
15. What are Device filtersand Protocol filters?
In ZyNOS, the filters have been separated into two groups.One group is called
'device filter group', and theotheris called'protocol filtergroup'. Generic
filters belong to the 'device filter group', TCP/IP and IPXfilters belong tothe
'protocol filter group'. Youcan configure the filter rule inSMT.
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-793Hv2's filter sets provide a means toprotect againstIP spoofing
attacks.The basic scheme is as follows:
Forthe input data filter:
 Deny packets from theoutsidethat claim to befrom theinside
 Alloweverything that is not spoofing us
Filter rule setup:
 Filtertype =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 isan IP address on yourlocalnetwork and w.x.y.z isyour
netmask:
Forthe output data filters:
 Deny bounce back packet
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P-793H v2 Support Notes
 Allowpackets that originate from us
Filter rule setup:
 FilterType =TCP/IP FilterRule
 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 isan IP address on yourlocalnetwork and w.x.y.z isyour
netmask.
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P-793H v2 Support Notes
ProductFAQ
1. What isSHDSL, SHDSL.bis?
SHDSL stands forSymmetric High-data-rate Digital Subscriber Line. SHDSL
bases on TC-PAM (Trellis Coded Pulse Amplitude Modulation) which offers
symmetrical transmission speed up to2.30 Mbps(2-wire mode).
SHDSL.bis boots SHDSL performance to approximately 5.70 Mbps(2-wire
mode)or 11.4 Mbps (4-wire mode).
2. How can I manage P-793H v2?
 Multilingual EmbeddedWeb GUIfor Local and Remote management
 SMTvia console.
 Telnet support (AdministratorPasswordProtected ) forremote
configuration change and statusmonitoring
 FTP/ TFTP sever, firmware upgradeand configurationbackupand
restore are supported (Administrator Password Protected)
3. What is the defaultpasswordfor Web Configurator?
There are twodifferent accounts for P-793Hv2 Web Configurator: Common
User Accountand Administrator Account.
By factory default thepasswordforthetwo accounts are:
 Common User Account: user
 Administrator Account: 1234.
You can change the password after you logging in the Web Configurator.
Note: By default, the password is “user”.
4. What‟s the difference between „Common User Account‟ and
„Administrator Account‟?
ForCommon UserAccount, it can only access the status monitor ofP-793Hv2
andcheck thecurrent systemstatus.
ForAdministrator Account,besides accessing thestatusmonitor of P-793Hv2,
it canalso access Wizardsetup/ AdvancedsetupofP-793Hv2.
Moreover, only withAdministratorPassword,youcould managethe P-793Hv2
via FTP/TFTP or Telnet.
5. How do I know the P-793H v2'sWAN IP addressassigned by the ISP?
Youcanview "IP Address: x.x.x.x" shown inWeb Configurator „Status-
>Device Information ->WAN Information‟.
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P-793H v2 Support Notes
6. What do I need before usingthe SHDSL?
1. You must order the SHDSL service from your telephone companyand
choosetheservicecategory.
2. Your telephone company musthave tested the phone line for the
SHDSL transfer rate.
3. You must have subscribed toan ISP ( Internet Service Provider)
already and have thefollowinginformation:
 The username and passwordforthe connection
 VPI/VCInumber (Virtual Path Indentifier/VirtualCircuitIdentifier)
assigned by the Tele company.
 The encapsulation protocol the service provider supports. It can be
PPP, RFC1483, orENETENCAP.
 The DNS and gateway, and ENETENCAP Gatewayifthe
encapsulation is ENETENCAP.
7. What should I do when the power(PWR) LED isoff?
Make sure the P-793H v2 is connected to the power adapter,the power adapter
is plugged into a power outlet and the powerswitch is at the ONposition.
8. How to debug while DSL LED isoff?
Check the connection between the P-793Hv2's DSLport and the wall socket or
remote devices. If you use the back toback application, check the service type
andtheStandardMode inboth P-793Hv2s.
9. How do I verify my PC'sIP addressassigned by the P-793H v2?
Make sureyouhave the P-793Hv2 powered on and then turn on yourPC.
AfterthePC starts, select " Run..." from thewindows"Start"menu.Enter"cmd"
andclick OK. YoumaycheckIP ofyourPC with “ipconfig”. Verify your cabling
if the IP address box shows "0.0.0.0".
10. What isTraffic Shaping?
Traffic Shaping is a feature in the P-793Hv2. It allocates thebandwidth to WAN
dynamicallyand aims at boosting the efficiency ofthe bandwidth.If there are
several VCs in the P-793Hv2 but only oneVC activated at one time, the P-793H
v2 allocates all the Bandwidth tothe VCand the VC getsfull bandwidth. If
another VCs areactivatedlater, thebandwidth isyield to otherVCs afterward.
11. What do the parameters(PCR, SCR, MBS) mean?
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P-793H v2 Support Notes
Traffic shaping parameters (PCR, SCR, MBS)can be setin Menu4 andMenu
11.6andis valid for both incomingand outgoingdirectionsince G.shdslis
symmetric.
Peak CellRate(PCR): The maximum bandwidth allocated tothis connection.
The VCconnectionthroughputis limitedbyPCR.
Sustainable Cell Rate(SCR): The least guaranteed bandwidth ofa VC.
When there aremulti-VCs on the same line,the VCthroughputis guaranteed
by SCR.
Maximum Burst Size(MBS): The amount ofcells transmittedthrough this VC
at the Peak Cell Rate before yielding to other VCs.Total bandwidth oftheline
is dedicated tosingle VCifthereis onlyone VCon the line. However, as the
other VC asking the bandwidth, the MBSdefines the maximumnumberofcells
transmitted via this VCwith Peak Cell rate before yielding tootherVCs.
The P-793H v2 holds the parameters for shaping the traffic among its virtual
channels. If you do not need traffic shaping, pleasesetSCR= 0, MBS= 0and
PCRas the maximum value according to the line rate (for example, 2.3 Mbps
line rate will result PCRas 5424 cell/sec.)
12. What do ATM QoS Types(CBR, UBR, VBR-nRT, VBR-RT) mean?
Constant bit rate(CBR): AnATM bandwidth-allocation service that requires
the user todetermine a fixed bandwidthrequirement at the time the connection
is set upsothat the data canbesentina steadystream.CBRservice is often
used when transmitting fixed-rate uncompressed video.
Unspecified bit rate(UBR): AnATM bandwidth-allocation service thatdoes
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 thatallows
users to specify a throughputcapacity(i.e., apeak rate)anda sustained rate
but data is not sent evenly. You can selectVBRforbusty traffic and bandwidth
sharing with otherapplications. It containstwo subclasses: Variablebit rate non
real time (VBR-nRT) and Variable bit rate real time (VBR-RT).
13. Why do we perform traffic shapingin the P-793H v2?
The P-793H v2 must manage traffic fairly and provide bandwidth allocation for
different sorts ofapplications, 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-793Hv2 is able tosupport variable traffic among
different virtual connections. Certaintraffic maybe discardedifthevirtual
connection experiences congestion. Traffic shaping defines a set ofactions
taken by the
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P-793H v2 Support Notes
P-793Hv2 toavoid congestion; traffic shaping takesmeasures toadapt to
unpredictable fluctuations intraffic flows and other problems among virtual
connections.
14. The P-793H v2 supportsBridge andRouter mode,what'sthe
difference betweenthem?
Whenthe ISP limitssome specificcomputers toaccessInternet, that means
only thetraffic to/from these computerswill be forwarded and the other will be
filtered. In this case, we use bridge mode whichworks as a DSL modem to
connect to theISP. The ISP will generallygive one Internet account and limit
only one computer toaccessthe Internet.
Formost Internet users having multiple computers want toshare an Internet
account for Internet access,they have toadd another Internet sharing device,
likea router. In this case, we use theroutermodewhich worksas a general
Router plus a DSL Modem.
15. How do I know I am using PPPoE?
PPPoE requires a user account to logintothe provider's server. If youneedto
configure a user name andpassword on yourcomputer 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. Pleasechoose PPPoE as
the encapsulation type inthe P-793H v2 ifthe ISP uses PPPoE.
16. Why doesmy provider use PPPoE?
PPPoE emulatesa familiarDial-Upconnection.It allows yourISP to provide
services using their existing network configuration over the broadband
connections.Besides, PPPoEsupports a broad range ofexisting applications
and service including authentication, accounting,secure accessand
configuration management.
17. What isDDNS?
The Dynamic DNS service allows you toalias a dynamic IP address toa static
hostname, allowing yourcomputertobemoreeasilyaccessedfrom various
locations on theInternet. Tousethe service, you mustfirst applyanaccount
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-793H
v2to reach our internal server. It is inconvenient for the users if this IP is
dynamic. With DDNS supported by the P-793H v2, you apply a DNS name
(e.g.,
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P-793H v2 Support Notes
www.zyxel.com.tw) foryourserver (e.g., Webserver)from a DDNS server.
The outside users can always access the webserver using the
www.zyxel.com.twregardlessoftheWAN IP ofthe P-793Hv2.
When the ISP assignsthe P-793Hv2 a new IP, the P-793H v2 updates this IP
toDDNS server sothat the server can update its IP-to-DNS entry.Once the
IP-to-DNS table in the DDNS serveris updated, theDNS name foryourweb
server (i.e., www.zyxel.com.tw)is still usable.
18. When do I needDDNS service?
Whenyou wantyour internalserver to be accessed by using DNS name rather
than using the dynamic IP address we can use theDDNS 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-793H v2 sends this IP to the DDNS
server for its updates.
19. What isDDNS wildcard? Doesthe P-793H v2support DDNS wildcard?
Some DDNS servers support the wildcard feature which allowsthe hostname,
*.yourhost.dyndns.org, tobe aliased tothe same IP address as
yourhost.dyndns.org. This featureis useful whenthere are multiple servers
insideand youwant users to beable to usethingssuch as
www.yourhost.dyndns.org and still reachyourhostname.
Yes, the P-793H v2 supports DDNS wildcard thathttp://www.dyndns.org/
supports. Whenusingwildcard, you simplyenteryourhost.dyndns.org in the
Host field inMenu 1.1 Configure Dynamic DNS.
20. Can the P-793H v2'sSUA handleIPSec packetssent by the
IPSec gateway?
Yes, the P-793H v2's SUA can handle IPSec ESPTunneling mode. We know
when packets go through SUA,SUA will change the source IP address and
source port forthehost. To pass IPSec packets, SUA mustunderstandthe
ESP packetwith protocol number 50, replace thesourceIP addressofthe
IPSec gateway to therouter's WAN IP address.However, SUA shouldnot
change thesource port ofthe UDP packetswhich are usedforkey
managements. Because the remote gatewaychecks thissource port during
connections,the port thusis notallowed to bechanged.
21. How do I setup my P-793H v2 for routing IPSec packetsover SUA?
Foroutgoing IPSec tunnels,no extra setting is required.
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P-793H v2 Support Notes
Forforwarding the inbound IPSec ESP tunnel,A 'Default'serverset is required.
You could configure it inWeb Configurator, Advanced Setup,Network -> NAT
-> Port Forwarding -> Default Server Setup:
It is because SUA makesyour LAN appear as a single machine tothe outside
world. LAN users are invisible tooutside users. So,to make aninternal server
for outsideaccess,wemustspecify theservice port and theLAN IP ofthis
server in Webconfigurator. Thus SUA is able toforward the incoming packets to
the requested service behind SUA and the outside users access the server
using the P-793H v2's WAN IP address. So, we haveto configuretheinternal
IPsec client as adefault server(unspecifiedservice port) whenit acts a server
gateway.
22. What isVLAN?
A VLAN (Virtual Local Area Network)allows aphysical network tobe partitioned
into multiple logical networks. Stationsona logical networkbelong to one group
calledVLANGroup. A stationcanbelong to more thanone group.
The stations on the same VLAN group can communicate with each other. With
VLAN, a station cannot directly talk toor hear from stations that are not inthe
same VLAN group(s); the traffic must firstgo through a router.
23. 802.1Q/1P
In order to resolve the limitation ofport basedVLAN,this framework of
802.1Q/1P feature is proposed. Thekey conceptsareas below:
One VLANgroup is treatedas “individual”device, just like therearemany
virtual devices ononephysical device.
Each LAN port, and PVC is similartoa VLANswitch port.Each canbe
grouped into any 802.1Q VLANgroup andindividually configuredas tagged
or untagged.
The PVIDof Each LANport, and PVCcanbeindividually configured.
In each VLAN group, it is allowedtohavemultiple bridge PVCs,route PVCs
or mixedPVCs.
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P-793H v2 Support Notes
24. What isTraffic Redirect ?
Traffic redirect forwards WANtraffic toa backup gatewaywhen the
Prestige cannot connect tothe Internet through it's normal gateway.
Thus make yourbackupgatewayas anauxiliary backupofyourWAN
connection. Once Prestige detects its WANconnectivity is broken,
Prestigewill try toforward outgoingtraffic to backupgatewaythatusers
specify in traffic redirect configuration menu.
25. What isDial Backup?
It is Auto Fail-over and Fall-back WAN Backup Solution.
The P-793Hv2 features a Fail-over and Fail-back WAN Backup Solution
for complete reliability. Whenthe DSL connection fails,traffic is forwarded
toeither a backup ISDNor analog modem to maintain data exchange.
When the DSL connectionis re-established,traffic will befully restored.
The WAN Backup Solution saves device maintenance cost and reduces
loss from daily operation.
In addition, P-793H v2 also performs backup functionsby redirecting traffic to
aspecific gateway toensure availabilityofthe Internet connection.
DSL FAQ
1. How doesDSL compare to Cable modems?
DSL provides a dedicated service over a single telephone line; cable modems
offer a dedicated service over a shared media. While cable modems have
greaterdownstream 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 ina neighborhood get online at the same time. Cable modem
upstream traffic will inmany casesbe slower than DSL, either because the
particular cable modem isinherentlyslower,or because ofrate reductions
caused by contention forupstream bandwidth slots. The big difference
between DSL and cable modems, however, is the number oflines available to
each. There are no more than 12 million homes passed todaythatcan support
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P-793H v2 Support Notes
two-way cable modem transmissions, and while the figure also grows steadily,it
will not catch upwith telephonelinesformany years. Additionally, many ofthe
oldercable networks arenot capable ofofferinga returnchannel; consequently,
such networks will need significant upgrading before they can offer high
bandwidth services.
2. How do I know the DSLline isup?
Youcansee the DSL LEDs on the P-793Hv2's front panel are on Green
when the DSL physical layer isup.
Note: There are two DSL LEDs: DSL1andDSL2.
WhenweuseonelineforInternet access or back toback application,DSL1
andDSL2will act thesameas one LED.
Whenweuse1-2back to back application by Y cable,they willshowthe
respective DSL line status.
3. How doesthe P-793H v2 work on a noisy DSL?
Depending on the line quality, the P-793Hv2 uses "Fall Back" and "Fall
Forward" toautomatically adjust the date rate.
4. Doesthe VC-based multiplexing perform better than the LLC-based
multiplexing?
Though the LLC-based multiplexing can carry multiple protocolsover a single
VC, it requires extra header information toidentify the protocol being carried
on the virtual circuit (VC). The VC-basedmultiplexingneedsa separate VCfor
carrying each protocol but it does not needtheextra headers. Therefore, the
VC-based multiplexing is more efficient.
5. How do I know the detailsof my DSL line statistics?
In WEB Configurator, Maintenance -> Diagnostic -> DSL Line -> DSL Line
Status:
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P-793H v2 Support Notes
6. What are the signalingpinsof the DSLconnector?
The signaling pins onthe P-793Hv2's DSL connectorRJ11cable are pin 3 and
4 for 2-wire mode, andpin 2, 3, 4 and 5 for 4-wiremode.
7. What istriple play?
More andmore Telco/ISPs areproviding three kinds of services (VoIP, Video
and Internet) over one existing DSL connection.
 The different services (such as video, VoIP and Internet access) require
different Quality ofService.
 The high priority is Voice (VoIP) data.
 The Medium priority is Video (IPTV) data.
 The low priority is internet access such as ftp etc …
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