Token-based correlation of control sessions for policy and charging control of a data session through a NAT

摘要

A method of handling packets sent across a packet switched network comprising a policy server acting as a policy and charging rules function. The method comprises providing a first set of policy rules at said policy server, and installing these from the policy server into an access gateway over a first service control session. These policy rules cause packets belonging to a given IP session to be diverted by the access gateway to a network address translator. At the network address translator, an IP source address of said packets is translated into a translated IP source address identifying a deep packet inspection node. The network address translator forwards the packets to the deep packet inspection node configured to perform deep packet inspection of IP packets.

主权项

1. A method of handling packets sent across a packet switched network comprising a policy server acting as a policy and charging rules function, the method comprising:
providing a first set of policy rules at said policy server, and installing the policy rules from the policy server into an access gateway over a first service control session, the policy rules causing packets belonging to a given IP session to be diverted by the access gateway to a network address translator; at the network address translator, translating an IP source address of said packets into a translated IP source address identifying a deep packet inspection node, and forwarding the packets to the deep packet inspection node configured to perform deep packet inspection of IP packets; providing a second set of policy rules at said policy server, and installing the second set of policy rules from the policy server into said deep packet inspection node over a second service control session, the second set of policy rules being applied by the deep packet inspection node to said packets upon receipt, allocating a token to said IP session that uniquely identifies the session, and providing the token to the policy server and the access gateway; sending said token from the access gateway to the deep packet inspection node via said network address translator; sending said token from the deep packet inspection node to the policy server; and at the policy server, using said token to associate said first and second service control sessions.