TMS zl Management and Configuration Guide ST.1.2.100916

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Virtual Private Networks
Configure an IPsec Client-to-Site VPN
5. For Encapsulation Mode, typically select Tunnel Mode.
Tunnel mode allows remote endpoints to reach services behind the TMS
zl Module. In transport mode, the VPN only supports traffic originated by
the remote endpoint or by the TMS zl Module itself. Therefore, this mode
is typically used when you are creating a proposal for GRE over IPsec site-
to-site VPNs or L2TP over IPsec client-to-site VPNs.
6. For Security Protocol, select AH or ESP.
7. If you selected ESP in the previous step, select one of the following for
Encryption Algorithm:
•NULL
If you select this option, VPN traffic will not be encrypted.
•DES
•3DES
• AES-128 (16)
• AES-192 (24)
• AES-256 (32)
The number in parentheses after AES options indicates the key length for
the algorithm in bytes.
8. If you selected either ESP or AH, for Authentication Algorithm, select one of
the following:
• None
You must not select None if you selected AH for the Security Protocol
or if you selected NULL for the ESP Encryption Algorithm.
•MD5
• SHA-1
•AES-XCBC
9. Click OK.
The IPsec proposal is displayed in the VPN > IPsec > IPsec Proposals window.
Figure 7-43. VPN > IPsec > IPsec Proposals Window (Proposal Added)