VPN

8

 

Configuring a Site-to-Site VPN

 

 

 

 

 

Configuring Transform Sets

A transform set specifies the algorithms of integrity and encryption that the peer will use to protect data communications. Two peers must use the same algorithm to communicate.

NOTE Up to 16 transform sets can be configured on the security appliance.

STEP 1 Click VPN > Site-to-Site > Transform Policies.

The Transform Sets window opens. The default and custom transform sets are listed in the table.

STEP 2 To add a new transform set, click Add.

Other options: To edit an entry, click the Edit (pencil) icon. To delete an entry, click the Delete (x) icon. To delete multiple entries, check them and click Delete. The default transform set (DefaultTrans) cannot be edited or deleted.

The Transform Set - Add/Edit window opens.

STEP 3 Enter the following information:

Name: Enter the name for the transform set.

Integrity: Choose the HASH algorithm used to ensure the data integrity. It ensures that a packet comes from where it says it comes from, and that it has not been modified in transit.

-ESP_SHA1_HMAC: Authentication with SHA1 (160-bit).

-ESP_MD5_HMAC: Authentication with MD5 (128-bit). MD5 has a smaller digest and is considered to be slightly faster than SHA1. A successful (but extremely difficult) attack against MD5 has occurred; however, the HMAC variant that IKE uses prevents this attack.

Encryption: Choose the symmetric encryption algorithm that protects data transmission between two IPsec peers. The default is ESP_3DES. The Advanced Encryption Standard supports key lengths of 128, 192, 256 bits.

-ESP_3DES: Encryption with 3DES (168-bit).

-ESP_AES_128: Encryption with AES (128-bit).

-ESP_AES_192: Encryption with AES (192-bit).

-ESP_AES_256: Encryption with AES (256-bit).

STEP 4 Click OK to save your settings.

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Casio ISA550WBUN3K9 manual Configuring Transform Sets, Click VPN Site-to-Site Transform Policies