Recommendations for Discovering IPv6 Prefix Used for IPv6 Address Synthesis
RFC 9872, “Recommendations for Discovering IPv6 Prefix Used for IPv6 Address Synthesis”, is an Informational document published in September 2025 by N. Buraglio, T. Jensen, J. Linkova. The canonical text is published by the RFC Editor.
Abstract
On networks providing IPv4-IPv6 translation (RFC 7915), hosts and other endpoints need to know the IPv6 prefix(es) used for translation (the NAT64 prefix (RFC 6052)). This document provides guidelines for NAT64 prefix discovery, specifically recommending obtaining the NAT64 prefix from the Router Advertisement option (RFC 8781) when available.
What “Informational” means
Published for the general information of the community. It does not define an IETF standard and carries no standards-track status.
The canonical text of RFC 9872 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.
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