Ike Phases; Figure 27-5 Two Phases To Set Up The Ipsec Sa - ZyXEL Communications ZyXEL ZyWALL 2WE User Manual

ZyWALL 2 and ZyWALL 2WE
LABEL
Encryption Algorithm
Authentication
Algorithm
Advanced
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.
In phase 1 you must:
27-12
Table 27-7 Basic IKE VPN Rule Setup
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.
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.
Click Advanced to configure more detailed settings of your IKE key management.

Figure 27-5 Two Phases to Set Up the IPSec SA

DESCRIPTION
VPN/IPSec Setup