Nortel Networks 620 User Manual

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Chapter 3
Configuration via Local Pages
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Page layout with
additional Networks
Clicking Specify Additional Networks allows you to designate up to four addresses/
subnets in case the Local Trusted Network can not be described by a single address/
subnet.
IKE Security Descriptor
The IKE Security Descriptor bundles the security parameters used for the IKE 
Security Association (Phase1).
A number of IKE Security Descriptors are pre-configured in the SpeedTouch™, and 
can be selected from a list. Select a Security Descriptor in function of your security 
requirements. The remote VPN clients must comply with the IKE security 
parameters configured in the VPN server.
For example, the pre-configured IKE Security Descriptor AES_MD5, used in various 
examples throughout this document, contains the following settings:  
The IKE Security Descriptor bundles the security parameters used for the IKE 
Security Association (Phase1).
Parameter
Value for 
AES_MD5
Cryptographic function
AES
Hash function
HMAC-MD5
Diffie-Hellman group
MODP768 (= group 1)
IKE SA lifetime in seconds.
3600 seconds (= 1 hour)
The contents of the IKE Security Descriptors can be verified via 
Advanced > Peers > Security Descriptors.
It is recommended to use AES as preferred encryption method. AES is more 
advanced, compared to DES or 3DES. It is faster for comparable key 
lengths, and provides better security.