ZyXEL ISG50-PSTN User Guide - Page 391

Extended Authentication, Certificates, IPSec SA Overview, Local Network and Remote Network

Page 391 highlights

Chapter 24 IPSec VPN • Configure the NAT router to forward packets with the extra header unchanged. (See the field description for detailed information about the extra header.) The extra header may be UDP port 500 or UDP port 4500, depending on the standard(s) the ISG50 and remote IPSec router support. Extended Authentication Extended authentication is often used when multiple IPSec routers use the same VPN tunnel to connect to a single IPSec router. For example, this might be used with telecommuters. In extended authentication, one of the routers (the ISG50 or the remote IPSec router) provides a user name and password to the other router, which uses a local user database and/or an external server to verify the user name and password. If the user name or password is wrong, the routers do not establish an IKE SA. You can set up the ISG50 to provide a user name and password to the remote IPSec router, or you can set up the ISG50 to check a user name and password that is provided by the remote IPSec router. If you use extended authentication, it takes four more steps to establish an IKE SA. These steps occur at the end, regardless of the negotiation mode (steps 7-10 in main mode, steps 4-7 in aggressive mode). Certificates It is possible for the ISG50 and remote IPSec router to authenticate each other with certificates. In this case, you do not have to set up the pre-shared key, local identity, or remote identity because the certificates provide this information instead. • Instead of using the pre-shared key, the ISG50 and remote IPSec router check the signatures on each other's certificates. Unlike pre-shared keys, the signatures do not have to match. • The local and peer ID type and content come from the certificates. Note: You must set up the certificates for the ISG50 and remote IPSec router first. IPSec SA Overview Once the ISG50 and remote IPSec router have established the IKE SA, they can securely negotiate an IPSec SA through which to send data between computers on the networks. Note: The IPSec SA stays connected even if the underlying IKE SA is not available anymore. This section introduces the key components of an IPSec SA. Local Network and Remote Network In an IPSec SA, the local network, the one(s) connected to the ISG50, may be called the local policy. Similarly, the remote network, the one(s) connected to the remote IPSec router, may be called the remote policy. ISG50 User's Guide 391

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Chapter 24 IPSec VPN
ISG50 User’s Guide
391
Configure the NAT router to forward packets with the extra header unchanged. (See the field
description for detailed information about the extra header.)
The extra header may be UDP port 500 or UDP port 4500, depending on the standard(s) the ISG50
and remote IPSec router support.
Extended Authentication
Extended authentication is often used when multiple IPSec routers use the same VPN tunnel to
connect to a single IPSec router. For example, this might be used with telecommuters.
In extended authentication, one of the routers (the ISG50 or the remote IPSec router) provides a
user name and password to the other router, which uses a local user database and/or an external
server to verify the user name and password. If the user name or password is wrong, the routers
do not establish an IKE SA.
You can set up the ISG50 to provide a user name and password to the remote IPSec router, or you
can set up the ISG50 to check a user name and password that is provided by the remote IPSec
router.
If you use extended authentication, it takes four more steps to establish an IKE SA. These steps
occur at the end, regardless of the negotiation mode (steps 7-10 in main mode, steps 4-7 in
aggressive mode).
Certificates
It is possible for the ISG50 and remote IPSec router to authenticate each other with certificates. In
this case, you do not have to set up the pre-shared key, local identity, or remote identity because
the certificates provide this information instead.
Instead of using the pre-shared key, the ISG50 and remote IPSec router check the signatures on
each other’s certificates. Unlike pre-shared keys, the signatures do not have to match.
The local and peer ID type and content come from the certificates.
Note: You must set up the certificates for the ISG50 and remote IPSec router first.
IPSec SA Overview
Once the ISG50 and remote IPSec router have established the IKE SA, they can securely negotiate
an IPSec SA through which to send data between computers on the networks.
Note: The IPSec SA stays connected even if the underlying IKE SA is not available
anymore.
This section introduces the key components of an IPSec SA.
Local Network and Remote Network
In an IPSec SA, the local network, the one(s) connected to the ISG50, may be called the local
policy. Similarly, the remote network, the one(s) connected to the remote IPSec router, may be
called the remote policy.