Chapter 20 IPSec VPN

Note: The ZyWALL and the remote IPSec router must use the same pre-shared key.

Router identity consists of ID type and content. The ID type can be domain name, IP address, or e- mail address, and the content is a (properly-formatted) domain name, IP address, or e-mail address. The content is only used for identification. Any domain name or e-mail address that you enter does not have to actually exist. Similarly, any domain name or IP address that you enter does not have to correspond to the ZyWALL’s or remote IPSec router’s properties.

The ZyWALL and the remote IPSec router have their own identities, so both of them must store two sets of information, one for themselves and one for the other router. Local ID type and content refers to the ID type and content that applies to the router itself, and peer ID type and content refers to the ID type and content that applies to the other router.

Note: The ZyWALL’s local and peer ID type and content must match the remote IPSec router’s peer and local ID type and content, respectively.

For example, in Table 114 on page 308, the ZyWALL and the remote IPSec router authenticate each other successfully. In contrast, in Table 115 on page 308, the ZyWALL and the remote IPSec router cannot authenticate each other and, therefore, cannot establish an IKE SA.

Table 114 VPN Example: Matching ID Type and Content

ZYWALL

REMOTE IPSEC ROUTER

 

Local ID type: E-mail

Local ID type: IP

 

 

 

 

Local ID content: tom@yourcompany.com

Local ID content: 1.1.1.2

 

 

 

 

Peer ID type: IP

Peer ID type: E-mail

 

 

 

 

Peer ID content: 1.1.1.2

Peer ID content: tom@yourcompany.com

 

 

 

 

Table 115 VPN Example: Mismatching ID Type and Content

 

ZYWALL

REMOTE IPSEC ROUTER

 

Local ID type: E-mail

Local ID type: IP

 

 

 

 

Local ID content: tom@yourcompany.com

Local ID content: 1.1.1.2

 

 

 

 

Peer ID type: IP

Peer ID type: E-mail

 

 

 

 

Peer ID content: 1.1.1.20

Peer ID content: tom@yourcompany.com

 

 

 

 

It is also possible to configure the ZyWALL to ignore the identity of the remote IPSec router. In this case, you usually set the peer ID type to Any. This is less secure, so you should only use this if your ZyWALL provides another way to check the identity of the remote IPSec router (for example, extended authentication) or if you are troubleshooting a VPN tunnel.

Additional Topics for IKE SA

This section provides more information about IKE SA.

Negotiation Mode

There are two negotiation modes--main mode and aggressive mode. Main mode provides better security, while aggressive mode is faster.

Main mode takes six steps to establish an IKE SA.

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ZyWALL 110/310/1100 Series User’s Guide