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Enhanced Port Forwarding functions with CGNAT

Document Type Expired Internet-Draft (individual)
Expired & archived
Author Louis Chan
Last updated 2023-09-08 (Latest revision 2023-03-07)
RFC stream (None)
Intended RFC status (None)
Stream Stream state (No stream defined)
Consensus boilerplate Unknown
RFC Editor Note (None)
IESG IESG state Expired
Telechat date (None)
Responsible AD (None)
Send notices to (None)

This Internet-Draft is no longer active. A copy of the expired Internet-Draft is available in these formats:


There is a need for peer-to-peer (P2P) communication under the use of CGNAT in service providers. With the combination of home gateway, this becomes NAT444. In RFC5128, methods of using UDP hole punching solves the problem partially when EIM (Endpoint-Independent Mapping) is supported in NAT device in the path, and there exists a common rendezvous server. The success rate of UDP hole punching is high, but not TCP hole punching in practical world. Also, the P2P solution requires a common server in the public internet to exchange the IP and port information. In this draft, a method is described to achieve incoming TCP or UDP session without a common rendezvous server in NAT444 situation.


Louis Chan

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)