Filter
Top Products
ZyWALL 2 and ZyWALL 2WE
27-12 VPN/IPSec Setup
Table 27-7 Basic IKE VPN Rule Setup
LABEL DESCRIPTION
Encryption Algorithm
Select DES, 3DES or NULL from the drop-down list box.
When DES is used for data communications, both sender and receiver must know 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. Select NULL to set up a
tunnel without encryption. When you select NULL, you do not enter an encryption key.
Authentication
Algorithm
Select SHA1 or MD5 from the drop-down list box. MD5 (Message Digest 5) and SHA1
(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-1 for maximum security.
Advanced
Click Advanced to configure more detailed settings of your IKE key management.
Click Apply to save your changes back to the ZyWALL. Click Reset to begin configuring this screen afresh.
27.10 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.
Figure 27-5 Two Phases to Set Up the IPSec SA
In phase 1 you must: