ZyWALL 2 Series User’s Guide

 

Table 14-7 Basic IKE VPN Rule Edit

 

 

LABEL

DESCRIPTION

 

 

Encryption

Select DES, 3DES, AES or NULL from the drop-down list box.

Algorithm

When you use one of these encryption algorithms for data communications, both the

 

 

sending device and the receiving device must use the same secret key, which can be

 

used to encrypt and decrypt the message or to generate and verify a message

 

authentication code. The DES encryption algorithm uses a 56-bit key. Triple DES (3DES)

 

is a variation on DES that uses a 168-bit key. As a result, 3DES is more secure than DES.

 

It also requires more processing power, resulting in increased latency and decreased

 

throughput. This implementation of AES uses a 128-bit key. AES is faster than 3DES.

 

Select NULL to set up a tunnel without encryption. When you select NULL, you do not

 

enter an encryption key.

 

 

Authentication

Select SHA1 or MD5 from the drop-down list box. MD5 (Message Digest 5) and SHA1

Algorithm

(Secure Hash Algorithm) are hash algorithms used to authenticate packet data. The SHA1

 

algorithm is generally considered stronger than MD5, but is slower. Select MD5 for

 

minimal security and SHA-1for maximum security.

 

 

AH

Select AH if you want to use AH (Authentication Header Protocol). The AH protocol (RFC

 

2402) was designed for integrity, authentication, sequence integrity (replay resistance),

 

and non-repudiation but not for confidentiality, for which the ESP was designed. If you

 

select AH here, you must select options from the Authentication Algorithm field

 

(described below).

 

 

Authentication

Select SHA1 or MD5 from the drop-down list box. MD5 (Message Digest 5) and SHA1

Algorithm

(Secure Hash Algorithm) are hash algorithms used to authenticate packet data. The SHA1

 

algorithm is generally considered stronger than MD5, but is slower. Select MD5 for

 

minimal security and SHA-1for maximum security.

 

 

Advanced

Click Advanced to configure more detailed settings of your IKE key management.

 

 

Apply

Click Apply to save your customized settings and exit this screen.

 

 

Reset

Click Reset to begin configuring this screen afresh.

 

 

14.12 IKE Phases

There are two phases to every IKE (Internet Key Exchange) negotiation – phase 1 (Authentication) and phase 2 (Key Exchange). A phase 1 exchange establishes an IKE SA and the second one uses that SA to negotiate SAs for IPSec.

VPN Screens

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