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A New Internet-Draft is available from the on-line Internet-Drafts directories.
Title : IPv4-Mapped Addresses on the Wire Considered Harmful
Author(s) : C. Metz, J. Hagino
Filename : draft-itojun-v6ops-v4mapped-harmful-01.txt
Pages : 5
Date : 2002-10-30
The IPv6 Addressing Architecture [Hinden, 1998] defines the 'IPv4-mapped
IPv6 address.' These addresses are used in the IPv6 basic API
[Gilligan, 1999] to denote IPv4 addresses using AF_INET6 sockets. These
addresses are used in protocol proposals such as SIIT [Nordmark, 2000]
to denote IPv6 communication using AF_INET6 sockets. Therefore,
IPv4-mapped addresses have two different meanings, and they are not
distinguishable from the user-land applications.
This draft discusses security threats due to this ambiguity of
IPv4-mapped address. It also discusses threats due to the additional
complexities introduced by IPv4-mapped addresses. Finally, it proposes
to resolve these problems by forbidding protocols from using IPv4-mapped
addresses for IPv6 communications.
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