RFC 4861, "Neighbor Discovery for IP version 6 (IPv6)", September 2007

Errata ID: 1595
Status: Verified
Type: Technical
Publication Format(s) : TEXT
Reported By: Teco Boot
Date Reported: 2008-11-11
Verifier Name: Brian Haberman
Date Verified: 2012-06-01

Section 2.2 says:

   asymmetric reachability
                  - a link where non-reflexive and/or non-transitive
                    reachability is part of normal operation.  (Non-
                    reflexive reachability means packets from A reach B,
                    but packets from B don't reach A.  Non-transitive
                    reachability means packets from A reach B, and
                    packets from B reach C, but packets from A don't
                    reach C.)  Many radio links exhibit these
                    properties.

It should say:

   asymmetric reachability
                  - a link where uni-directional and/or non-transitive
                    reachability is part of normal operation.  (Uni-
                    directional reachability means packets from A reach B,
                    but packets from B don't reach A.  Non-transitive
                    reachability means packets from A reach B, and
                    packets from B reach C, but packets from A don't
                    reach C.)  Many radio links exhibit these
                    properties.

Notes:

Discussed on Autoconf ML:
http://www.ietf.org/mail-archive/web/autoconf/current/msg01119.html
Term non-reflexive link is "link to itself". To be replaced with either asymmetric, non-symmetric or uni-directional. Asymmetric and Non-symmetric are confusing as those are often used for asymmetric link metrics (e.g. ADSL, UMTS/HSPDA).

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