IAB Considerations for UNilateral Self-Address Fixing Across Network Address Translation

Abstract

As a result of the nature of Network Address Translation (NAT) Middleboxes, communicating endpoints that are separated by one or more NATs do not know how to refer to themselves using addresses that are valid in the addressing realms of their (current and future) peers. Various proposals have been made for "UNilateral Self-Address Fixing (UNSAF)" processes. These are processes whereby some originating endpoint attempts to determine or fix the address (and port) by which it is known to another endpoint - e.g., to be able to use address data in the protocol exchange, or to advertise a public address from which it will receive connections. This document outlines the reasons for which these proposals can be considered at best as short term fixes to specific problems and the specific issues to be carefully evaluated before creating an UNSAF proposal. This memo provides information for the Internet community.

Abstract as published in the RFC, via rfc-editor.org.

What “Informational” means

Published for the general information of the community. It does not define an IETF standard and carries no standards-track status.