Table 51 Vpn: Types Of Encryption And Authentication In Esp And Ah - ZyXEL Communications ZyWALL 2Plus User Manual

ZyWALL 2 Plus User's Guide
There is a relationship between the active protocol and the types of encryption and
authentication algorithms that are available. This relationship is illustrated in
188, where more information is also provided about each type of encryption and
authentication algorithm.

Table 51 VPN: Types of Encryption and Authentication in ESP and AH

Encryption
Authentication
188
ESP
DES
Data Encryption Standard (DES) is a
widely used method of data encryption
using a secret key. DES applies a 56-bit
key to each 64-bit block of data.
3DES
Triple DES (3DES) is a variant of DES,
which iterates three times with three
separate keys (3 x 56 = 168 bits),
effectively doubling the strength of DES.
AES
Advanced Encryption Standard is a
newer method of data encryption that
also uses a secret key. This
implementation of AES applies a 128-bit
key to 128-bit blocks of data. AES is
faster than 3DES.
Select NULL to set up an IPSec SA
without encryption.
MD5
MD5 (Message Digest 5) produces a
128-bit digest to authenticate packet
data.
SHA1
SHA1 (Secure Hash Algorithm) produces
a 160-bit digest to authenticate packet
data.
Select MD5 for minimal security and SHA1 for maximum security.
Table 51 on page
AH
MD5
MD5 (Message Digest 5) produces a
128-bit digest to authenticate packet
data.
SHA1
SHA1 (Secure Hash Algorithm) produces
a 160-bit digest to authenticate packet
data.
Chapter 11 IPSec VPN