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IPv4-Mapped Address API Considered Harmful

Document Type Expired Internet-Draft (individual)
Expired & archived
Authors Christopher Y. Metz , Jun-ichiro Itoh
Last updated 2003-10-23
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This Internet-Draft is no longer active.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:


The IPv6 Addressing Architecture [Hinden, 1998] defines the 'IPv4-mapped IPv6 address.' This representation is used in the IPv6 basic API [Gilligan, 1999] to denote IPv4 addresses using AF_INET6 sockets. The use of IPv4-mapped addresses on AF_INET6 sockets degrades portability, complicates IPv6 systems, and is likely to create security problems. This document discusses each issue in turn. Finally, it proposes to resolve these problems by recommending deprecation of this mechanism.


Christopher Y. Metz
Jun-ichiro Itoh

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