Nortel Networks 608(WL) Manuale Utente

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Chapter 2
SpeedTouch™ IPSec terminology
E-DOC-CTC-20051017-0169 v1.0
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2.1 Policy
What is ...
Security is all about traffic policies and these can be configured using the IPSec 
policy commands. By default, policy rules are automatically generated when the 
IPSec connection is created and the user does not need to execute extra commands.
A set of rules defines whether a packet has to pass through a secure tunnel or not. 
These rules are expressed in terms of IP addresses, protocols and/or ports that have 
access to the secure connections. The user specifies and configures a general policy 
in function of his overall security policy and the VPN network topology.
Static policy
In a static network environment with fixed IP addresses, the policy can be 
completely defined, and specific rules can be expressed in the configuration.
Dynamic policy
In a more dynamic network environment, where IP addresses are dynamically 
assigned, or where terminals may connect from various unknown locations, it may 
be impossible to express a specific policy in the router configuration. In order to 
cope with this situation, the SpeedTouch™ allows expressing a general policy in the 
configuration. This general policy may include some placeholders for information 
that becomes available only during the Security Association negotiations. The 
specific policy rules are automatically derived from the general policy and the 
outcome of the negotiations.