ZyXEL Communications LTE6100 User Manual

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Chapter 13 VPN
LTE6100 User’s Guide
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13.3  Technical Reference
This section provides some technical background information about the topics covered in this 
section.
13.3.1  IPSec Architecture
The overall IPSec architecture is shown as follows.
Figure 51   
IPSec Architecture
IPSec Algorithms
The ESP (Encapsulating Security Payload) Protocol (RFC 2406) and AH (Authentication Header) 
protocol (RFC 2402) describe the packet formats and the default standards for packet structure 
(including implementation algorithms).
The Encryption Algorithm describes the use of encryption techniques such as DES (Data Encryption 
Standard) and Triple DES algorithms.
The Authentication Algorithms, HMAC-MD5 (RFC 2403) and HMAC-SHA-1 (RFC 2404, provide an 
authentication mechanism for the AH and ESP protocols. 
Key Management
Key management allows you to determine whether to use IKE (ISAKMP) or manual key 
configuration in order to set up a VPN.