ZyXEL Communications Prestige 2602H-6xC Manual

Prestige 2602H-6xC
ADSL VoIP IAD
Support Notes
Version 3.40
March. 2005

Prestige 2602H-6xC Support Notes
All contents copyright (c) 2005 ZyXEL Communications Corporation. 2
INDEX
Application Notes.........................................................................................................8
General Application Notes.....................................................................................8
Internet Connection................................................................................................8
Setup the Prestige as a DHCP Relay............................................................11
Configure an Internal Server Behind SUA..................................................13
Configure a PPTP server Behind SUA ........................................................15
Using NAT / Multi-NAT..............................................................................19
About Filter & Filter Examples ...................................................................40
Using the Dynamic DNS (DDNS)...............................................................63
Network Management Using SNMP...........................................................65
Using syslog.................................................................................................71
Using IPAlias ..............................................................................................75
Using Call Scheduling .................................................................................77
Using IP Multicast .......................................................................................82
Using Prestige traffic redirect......................................................................84
Using Universal Plug n Play (UPnP)...........................................................87
VoIPApplication Notes........................................................................................92
Setup SIP Account.......................................................................................92
Phone port settings.......................................................................................96
Phone book Speed dial.................................................................................98
FAQ ...........................................................................................................................100
ZyNOS FAQ ......................................................................................................100
What is ZyNOS?........................................................................................100
How do I access the embedded web configurator?....................................100
What is the default LAN IP address and Password? Moreover, how do I
change it?...................................................................................................101
How do I upload the ZyNOS firmware code via embeded web
configurator?..............................................................................................101
How do I upgrade/backup the ZyNOS firmware by using FTP client
program via LAN?.....................................................................................101
How do I upload or backup ROMFILE via web configurator?.................102
How do I backup/restore configurations by using FTP client program via
LAN?..........................................................................................................102
Why can't I make Telnet to Prestige from WAN?.....................................102
What should I do if I forget the system password?....................................103

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What is SUA? When should I use SUA?...................................................103
What is the difference between NAT and SUA?.......................................103
How many network users can the SUA/NAT support?.............................104
What are Device filters and Protocol filters?.............................................104
Why can't I configure device filters or protocol filters?............................104
Product FAQ ......................................................................................................104
What is the Prestige Integrated Access Device?........................................104
Will the Prestige work with my Internet connection?................................105
What do I need to use the Prestige?...........................................................105
What is PPPoE? .........................................................................................105
Does the Prestige support PPPoE?.............................................................105
How do I know I am using PPPoE?...........................................................105
Why does my provider use PPPoE?...........................................................106
Which Internet Applications can I use with the Prestige? .........................106
How can I configure the Prestige?.............................................................106
What network interface does the Prestige support?...................................106
What can we do with Prestige?..................................................................106
Does Prestige support dynamic IP addressing? .........................................106
What is the difference between the internal IP and the real IP from my ISP?
....................................................................................................................106
How does e-mail work through the Prestige?............................................107
Is it possible to access a server running behind SUA from the outside
Internet? If possible, how?.........................................................................107
What DHCP capability does the Prestige support?....................................107
How do I used the reset button, more over what field of parameter will be
reset by reset button? .................................................................................107
What network interface does the new Prestige series support?.................108
How does the Prestige support TFTP?.......................................................108
Can the Prestige support TFTP over WAN? ..............................................108
How fast can the data go?..........................................................................108
What is Multi-NAT? ..................................................................................109
When do I need Multi-NAT? .....................................................................109
What IP/Port mapping does Multi-NAT support? .....................................110
What is the difference between SUA and Multi-NAT? .............................111
What is BOOTP/DHCP?............................................................................111
What is DDNS?..........................................................................................111
When do I need DDNS service?................................................................112

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What DDNS servers does the Prestige support?........................................112
What is DDNS wildcard?...........................................................................112
Does the Prestige support DDNS wildcard?..............................................112
Can the Prestige SUA handle IPsec packets sent by the VPN gateway
behind Prestige?.........................................................................................112
How do I setup my Prestige for routing IPsec packets over SUA?...........113
VoIP FAQ...........................................................................................................113
What is Voice over IP?..............................................................................113
How does Voice over IP work?.................................................................113
Why use VoIP?..........................................................................................113
What is the relationship between codec and VoIP?...................................114
What advantage does Voice over IP can provide?.....................................114
What is the difference between H.323 and SIP?........................................114
Can H.323 and SIP interoperate with one another?...................................114
What is voice quality?................................................................................114
How are voice quality normally rated?......................................................114
What is codec?...........................................................................................115
What is the relation of codec and VoIP? ...................................................115
What codec does Prestige support?............................................................115
Which codec should I choose?...................................................................115
What do I need in order to use SIP? ..........................................................115
Unable to register with the SIP server?......................................................116
I can register but can not establish a call?..................................................116
I can make a call but the voice only goes one way not bothway?.............116
I can receive a call but the voice only goes one way not bothway? ..........116
If all the about have been tried, but register still fail what should I do?....117
I suspect there is a hardware problem with my Prestige what should I do?117
Firewall FAQ .....................................................................................................117
What is a network firewall?.......................................................................117
What makes Prestige firewall secure? .......................................................117
What are the basic types of firewalls? .......................................................118
What kind of firewall is the Prestige?........................................................118
Why do you need a firewall when your router has packet filtering and
NAT built-in?.............................................................................................119
What is Denials of Service (DoS)attack?...................................................119
What is Ping of Death attack?....................................................................119
What is Teardrop attack?...........................................................................119

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What is SYN Flood attack?........................................................................119
What is LAND attack?...............................................................................120
What is Brute-force attack? .......................................................................120
What is IP Spoofing attack?.......................................................................120
What are the default ACL firewall rules in Prestige?................................120
How can I protect against IP spoofing attacks?.........................................121
Content Filter FAQ ............................................................................................122
IPSec FAQ .........................................................................................................122
What is VPN? ............................................................................................122
Why do I need VPN?.................................................................................123
What are most common VPN protocols?...................................................123
What is PPTP? ...........................................................................................123
What is L2TP? ...........................................................................................124
What is IPSec?...........................................................................................124
What secure protocols does IPSec support? ..............................................124
What are the differences between 'Transport mode' and 'Tunnel mode?...124
What is SA? ...............................................................................................125
What is IKE?..............................................................................................125
What is Pre-Shared Key?...........................................................................125
What are the differences between IKE and manual key VPN? .................125
What is Phase 1 ID for?.............................................................................125
What are Local ID and Peer ID?................................................................126
When should I use FQDN?........................................................................126
Is my Prestige ready for IPSec VPN?........................................................126
How do I configure Prestige VPN? ...........................................................127
How many VPN connections does Prestige support?................................127
What VPN protocols are supported by Prestige?.......................................127
What types of encryption does Prestige VPN support?.............................127
What types of authentication does Prestige VPN support? .......................127
I am planning my Prestige-to-Prestige VPN configuration. What do I need
to know?.....................................................................................................127
Does Prestige support dynamic secure gateway IP?..................................128
What VPN gateway that has been tested with Prestige successfully?.......128
What VPN software that has been tested with Prestige successfully?.......129
Will ZyXEL support Secure Remote Management?..................................129
Does Prestige VPN support NetBIOS broadcast? .....................................129
Is the host behind NAT allowed to use IPSec?..........................................129

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Why does VPN throughput decrease when staying in SMT menu 24.1?..129
Where can I configure Phase 1 ID in Prestige? .........................................130
If I have NAT router between two VPN gateways, and I would like to use
IP type as Phase 1 ID, what should I know?..............................................130
How can I keep a tunnel alive?..................................................................131
Single, Range, Subnet, which types of IP address do Prestige
10/10II/10W/50/100 support in VPN/IPSec? ............................................131
Can Prestige support IPSec passthrough?..................................................131
Can Prestige behave as a NAT router supporting IPSec passthrough and an
IPSec gateway simultaneously?.................................................................132
Wireless FAQ...................................................................錯誤! 尚未定義書籤。
What is a Wireless LAN ? ....................................... 錯誤! 尚未定義書籤。
What are the advantages of Wireless LANs ? ......... 錯誤! 尚未定義書籤。
What are the disadvantages of Wireless LANs ?..... 錯誤! 尚未定義書籤。
Where can you find wireless 802.11 networks ? ..... 錯誤! 尚未定義書籤。
What is an Access Point ?........................................ 錯誤! 尚未定義書籤。
What is IEEE 802.11 ?............................................. 錯誤! 尚未定義書籤。
What is 802.11b ? .................................................... 錯誤! 尚未定義書籤。
How fast is 802.11b ?............................................... 錯誤! 尚未定義書籤。
What is 802.11a ?..................................................... 錯誤! 尚未定義書籤。
What is 802.11g ? .................................................... 錯誤! 尚未定義書籤。
Is it possible to use products from a variety of vendors ?錯誤! 尚未定義書籤。
What is Wi-Fi ?........................................................ 錯誤! 尚未定義書籤。
What types of devices use the 2.4GHz Band ?........ 錯誤! 尚未定義書籤。
Does the 802.11 interfere with Bluetooth devices ? 錯誤! 尚未定義書籤。
Can radio signals pass through walls ?.................... 錯誤! 尚未定義書籤。
What are potential factors that may causes interference among WLAN
products ?................................................................. 錯誤! 尚未定義書籤。
What's the difference between a WLAN and a WWAN ?錯誤! 尚未定義書籤。
What is Ad Hoc mode ?........................................... 錯誤! 尚未定義書籤。
What is Infrastructure mode ?.................................. 錯誤! 尚未定義書籤。
How many Access Points are required in a given area ?錯誤! 尚未定義書籤。
What is Direct-Sequence Spread Spectrum Technology – (DSSS) ?錯誤! 尚未定義書籤。
What is Frequency-hopping Spread Spectrum Technology – (FHSS) ?錯誤! 尚未定義書籤。
Do I need the same kind of antenna on both sides of a link ?錯誤! 尚未定義書籤。
Why the 2.4 Ghz Frequency range ?........................ 錯誤! 尚未定義書籤。
What is Server Set ID (SSID) ? ............................... 錯誤! 尚未定義書籤。

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What is an ESSID ?.................................................. 錯誤! 尚未定義書籤。
How do I secure the data across an Access Point's radio link ?錯誤! 尚未定義書籤。
What is WEP ?......................................................... 錯誤! 尚未定義書籤。
What is the difference between 40-bit and 64-bit WEP ?錯誤! 尚未定義書籤。
What is a WEP key ? ............................................ 錯誤! 尚未定義書籤。
A WEP key is a user defined string of characters used to encrypt and
decrypt data ?........................................................... 錯誤! 尚未定義書籤。
Can the SSID be encrypted ?................................ 錯誤! 尚未定義書籤。
By turning off the broadcast of SSID, can someone still sniff the SSID ?錯誤! 尚未定義書籤
What are Insertion Attacks ?.................................... 錯誤! 尚未定義書籤。
What is Wireless Sniffer ? ....................................... 錯誤! 尚未定義書籤。
What is the difference between Open System and Shared Key of
Authentication Type ?.............................................. 錯誤! 尚未定義書籤。
What is 802.1x ? ...................................................... 錯誤! 尚未定義書籤。
What is the difference between No authentication required, No access
allowed and Authentication required ?.................... 錯誤! 尚未定義書籤。
What is AAA ?......................................................... 錯誤! 尚未定義書籤。
What is RADIUS ?................................................... 錯誤! 尚未定義書籤。
What is WPA ?......................................................... 錯誤! 尚未定義書籤。
What is WPA-PSK?................................................. 錯誤! 尚未定義書籤。
Trouble Shooting......................................................................................................132
Using Embedded Packet Trace ..........................................................................132
Debug PPPoE Connection .................................................................................147
CLI Command List..................................................................................................159

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Application Notes
General Application Notes
Internet Connection
A typical Internet access application of the Prestige is shown below. For a small office, there are some
components needs to be checked before accessing the Internet.
•Before you begin
•Setting up the Windows
•Setting up the Prestige router
•Troubleshooting
•Before you begin
The Prestige is shipped with the following factory default:
1. IP address = 192.168.1.1, subnet mask = 255.255.255.0 (24 bits)
2. DHCP server enabled with IP pool starting from 192.168.1.33
3. Default SMT menu password = 1234
•Setting up the PC (Windows OS)
1. Ethernet connection
All PCs must have an Ethernet adapter card installed.

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•If you only have one PC, connect the PC's Ethernet adapter to the Prestige's LAN port with a
crossover (red one) Ethernet cable.
•If you have more than one PC, both the PC's Ethernet adapters and the Prestige's LAN port must
be connected to an external hub with straight Ethernet cable.
2. TCP/IP Installation
You must first install TCP/IP software on each PC before you can use it for Internet access. If you have already
installed TCP/IP, go to the next section to configure it; otherwise, follow these steps to install:
•In the Control Panel/Network window, click Add button.
•In the Select Network Component Type windows, select Protocol and click Add.
•In the Select Network Protocol windows, select Microsoft from the manufacturers, then select
TCP/IP from the Network Protocols and click OK.
3. TCP/IP Configuration
Follow these steps to configure Windows TCP/IP:
•In the Control Panel/Network window, click the TCP/IP entry to select it and click Properties
button.
•In the TCP/IP Properties window, select obtain an IP address automatically.
Note: Do not assign arbitrary IP address and subnet mask to your PCs, otherwise, you will not be able to access
the Internet.
•Click the WINS configuration tab and select Disable WINS Resolution.
•Click the Gateway tab. Highlight any installed gateways and click the Remove button until there
are none listed.
•Click the DNS Configuration tab and select Disable DNS.
•Click OK to save and close the TCP/IP properties window
•Click OK to close the Network window. You will be prompted to insert your Windows CD or disk.
When the drivers are updated, you will be asked if you want to restart the PC. Make sure your
Prestige is powered on before answering Yes to the prompt. Repeat the above steps for each
Windows PC on your network.
•Setting up the Prestige router

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The following procedure is for the most typical usage of the Prestige where you have a single-user account
(SUA). The Prestige supports embedded web server that allows you to use Web browser to configure it. Before
configuring the router using Browser please be sure there is no Telnet or Console login.
1. Retrieve Prestige Web
Please enter the LAN IP address of the Prestige router in the URL location to retrieve the web screen from the
Prestige. The default LAN IP of the Prestige is 192.168.1.1. See the example below. Note that you can either
use http://192.168.1.1
2. Login first
The default password is the default SMT password, '1234'.
3. Configure Prestige for Internet access by using WIZARD SETUP
The Web screen shown below takes PPPoE as the example.

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Select “Dynamic＂ if the ISP provides the IP dynamically, otherwise select “Use Fixed IP address＂ and
enter the static IP given by ISP in the box following“MY WAN IP Address＂field.
Setup the Prestige as a DHCP Relay
•What is DHCP Relay?
DHCP stands for Dynamic Host Configuration Protocol. In addition to the DHCP server feature, the P2602
supports the DHCP relay function. When it is configured as DHCP server, it assigns the IP addresses to the
LAN clients. When it is configured as DHCP relay, it is reponsable for forwarding the requests and responses
negotiating between the DHCP clients and the server. See figure 1.

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•Setup the Prestige as a DHCP Client
1. Toggle the DHCP to Relay in menu 3.2 and enter the IP address of the DHCP server in the 'Relay Server
Address' field.
Menu 3.2 - TCP/IP and DHCP Setup
DHCP Setup
DHCP= Relay
Client IP Pool Starting Address= N/A
Size of Client IP Pool= N/A
Primary DNS Server= N/A
Secondary DNS Server= N/A
Remote DHCP Server= 192.168.1.2
TCP/IP Setup:
IP Address= 192.168.1.1
IP Subnet Mask= 255.255.255.0
RIP Direction= None
Version= N/A
Multicast= None
IP Policies=
Edit IP Alias= No

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Press ENTER to Confirm or ESC to Cancel:
Configure an Internal Server Behind SUA
•Introduction
If you wish, you can make internal servers (e.g., Web, ftp or mail server) accessible for outside users, even
though SUA makes your LAN appear as a single machine to the outside world. A service is identified by the
port number. Also, since you need to specify the IP address of a server in the Prestige, a server must have a
fixed IP address and not be a DHCP client whose IP address potentially changes each time it is powered on.
In addition to the servers for specific services, SUA supports a default server. A service request that does not
have a server explicitly designated for it is forwarded to the default server. If the default server is not defined,
the service request is simply discarded.
•Configuration
To make a server visible to the outside world, specify the port number of the service and the inside address of
the server in 'Menu 15.2.1', Multiple Server Configuration. The outside users can access the local server using
the Prestige's WAN IP address which can be obtained from menu 24.1.

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•For example (Configuring an internal Web server for outside access) :
Menu 15.2 - NAT Server Setup
Rule Start Port No. End Port No. IP Address
---------------------------------------------------
1. Default Default 0.0.0.0
2. 80 80 192.168.1.10
3. 0 0 0.0.0.0
4. 0 0 0.0.0.0
5. 0 0 0.0.0.0
6. 0 0 0.0.0.0
7. 0 0 0.0.0.0
8. 0 0 0.0.0.0
9. 0 0 0.0.0.0
10. 0 0 0.0.0.0
11. 0 0 0.0.0.0
12. 0 0 0.0.0.0
Press ENTER to Confirm or ESC to Cancel:
•Port numbers for some services
Service Port Number
FTP 21
Telnet 23
SMTP 25
DNS (Domain Name Server) 53
www-http (Web) 80

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Configure a PPTP server Behind SUA
•Introduction
PPTP is a tunneling protocol defined by the PPTP forum that allows PPP packets to be encapsulated within
Internet Protocol (IP) packets and forwarded over any IP network, including the Internet itself.
In order to run the Windows 9x PPTP client, you must be able to establish an IP connection with a tunnel server
such as the Windows NT Server 4.0 Remote Access Server.
Windows Dial-Up Networking uses the Internet standard Point-to-Point (PPP) to provide a secure,optimized
multiple-protocol network connection over dial-up telephone lines. All data sent over this connection can be
encrypted and compressed, and multiple network level protocols (TCP/IP, NetBEUI and IPX) can be run
correctly. Windows NT Domain Login level security is preserved even across the Internet.
Window98 PPTP Client / Internet / NT RAS Server Protocol Stack
PPTP appears as new modem type (Virtual Private Networking Adapter) that can be selected when setting up a
connection in the Dial-Up Networking folder. The VPN Adapter type does not appear elsewhere in the system.
Since PPTP encapsulates its data stream in the PPP protocol, the VPN requires a second dial-up adapter. This
second dial-up adapter for VPN is added during the installation phase of the Upgrade in addition to the first
dial-up adapter that provides PPP support for the analog or ISDN modem.

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The PPTP is supported in Windows NT and Windows 98 already. For Windows 95, it needs to be upgraded by
the Dial-Up Networking 1.2 upgrade.
•Configuration
This application note explains how to establish a PPTP connection with a remote private network in the Prestige
SUA case. In ZyNOS, all PPTP packets can be forwarded to the internal PPTP Server (WinNT server) behind
SUA. The port number of the PPTP has to be entered in the SMT Menu 15 for Prestige to forward to the
appropriate private IP address of Windows NT server.
•Example
The following example shows how to dial to an ISP via the Prestige and then establish a tunnel to a private
network. There will be three items that you need to set up for PPTP application, these are PPTP server (WinNT),
PPTP client (Win9x) and the Prestige.
oPPTP server setup (WinNT)
Add the VPN service from Control Panel>Network
Add an user account for PPTP logged on user
Enable RAS port
Select the network protocols from RAS such as IPX, TCP/IP NetBEUI
Set the Internet gateway to Prestige
oPPTP client setup (Win9x)
Add one VPN connection from Dial-Up Networking by entering the correct
username & password and the IP address of the Prestige's Internet IP address for
logging to NT RAS server.

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Set the Internet gateway to the router that is connecting to ISP
oPrestige router setup
•Before making a VPN connection from Win9x to WinNT server, you need to connect Prestige
router to your ISP first.
•Enter the IP address of the PPTP server (WinNT server) and the port number for PPTP as shown
below.
Menu 15.2 - NAT Server Setup (Used for SUA Only)
Rule Start Port No. End Port No. IP Address
---------------------------------------------------
1. Default Default 0.0.0.0
2. 1723 1723 192.168.1.10
3. 0 0 0.0.0.0
4. 0 0 0.0.0.0
5. 0 0 0.0.0.0
6. 0 0 0.0.0.0
7. 0 0 0.0.0.0
8. 0 0 0.0.0.0
9. 0 0 0.0.0.0
10. 0 0 0.0.0.0
11. 0 0 0.0.0.0
12. 0 0 0.0.0.0
Press ENTER to Confirm or ESC to Cancel:
When you have finished the above settings, you can ping to the remote Win9x client from
WinNT. This ping command is used to demonstrate that remote the Win9x can be reached across the
Internet. If the Internet connection between two LANs is achieve, you can place a VPN call from the
remote Win9x client.
For example:

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C:\ping 203.66.113.2
When a dial-up connection to ISP is established, a default gateway is assigned to the router traffic
through that connection. Therefore, the output below shows the default gateway of the Win9x client
after the dial-up connection has been established.
Before making a VPN connection from the Win9x client to the NT server, you need to know the exact
Internet IP address that the ISP assigns to Prestige router in SUA mode and enter this IP address in the
VPN dial-up dialog box. You can check this Internet IP address from PNC Monitor or SMT Menu
24.1. If the Internet IP address is a fixed IP address provided by ISP in SUA mode, then you can
always use this IP address for reaching the VPN server.
In the following example, the IP address '140.113.1.225' is dynamically assigned by ISP. You must
enter this IP address in the 'VPN Server' dialog box for reaching the PPTP server. After the VPN link is
established, you can start the network protocol application such as IP, IPX and NetBEUI.

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Using NAT / Multi-NAT
•What is Multi-NAT?
NAT (Network Address Translation-NAT RFC 1631) is the translation of an Internet Protocol address used
within one network to a different IP address known within another network. One network is designated the
inside network and the other is the outside . Typically, a company maps its local inside network addresses to one
or more global outside IP addresses and "unmaps" the global IP addresses on incoming packets back into local
IP addresses. The IP addresses for the NAT can be either fixed or dynamically assigned by the ISP. In addition,
you can designate servers, e.g., a web server and a telnet server, on your local network and make them
accessible to the outside world. If you do not define any servers, NAT offers the additional benefit of firewall
protection. In such case, all incoming connections to your network will be filtered out by the Prestige, thus
preventing intruders from probing your network.
The SUA feature that the Prestige supports previously operates by mapping the private IP addresses to a global
IP address. It is only one subset of the NAT. The Prestige with ZyNOS V3.40 supports the most of the features
of the NAT based on RFC 1631, and we call this feature as 'Multi-NAT'. For more information on IP address
translation, please refer to RFC 1631, The IP Network Address Translator (NAT) .
•How NAT works
If we define the local IP addresses as the Internal Local Addresses (ILA) and the global IP addresses as the
Inside Global Address (IGA), see the following figure. The term 'inside' refers to the set of networks that are
subject to translation. NAT operates by mapping the ILA to the IGA required for communication with hosts on
other networks. It replaces the original IP source address (and TCP or UDP source port numbers) and then
forwards each packet to the Internet ISP, thus making them appear as if they had come from the NAT system
itself (e.g., the Prestige router). The Prestige keeps track of the original addresses and port numbers so incoming
reply packets can have their original values restored.

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1. NAT Mapping Types
NAT supports five types of IP/port mapping. They are:
2. One to One
In One-to-One mode, the Prestige maps one ILA to one IGA.
3. Many to One
In Many-to-One mode, the Prestige 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
only option in today's routers).
4. Many to Many Overload
In Many-to-Many Overload mode, the Prestige maps the multiple ILA to shared IGA.
5. Many to Many No Overload
In Many-to-Many No Overload mode, the Prestige maps each ILA to unique IGA.
•Server
In Server mode, the Prestige 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.