Solution Model of Source Address Tracing for Carrier Grade NAT (CGN)
Huawei Symantec
Since NAT function on CGN box will make the IPv4 address re-used by more than one user, the packets sent outside CGN are not able to be identifid where they are from or which user they belong to according to the source address within the packets. However, under some certain circumstances, knowing the original source IP address and the identity of the user who sends the packet out is necessary. This document states the requirement of source address tracing briefly, and discusses the possible solution models for this issue.