Subject: RE: AD review of draft-ietf-6man-subnet-model

From: "Hemant Singh (shemant)" <[email-masked]>
Date: Wed, 3 Mar 2010 10:12:58 -0600

Jari,

Could you please review the new text and see if the example is able to
explain what we meant by an "invented prefix" and let us know if new
text looks ok.  

OLD:

4.  Observed Incorrect Implementation Behavior

One incorrect implementation behavior illustrates the severe
consequences when the IPv6 subnet model is not understood by the
implementers of several popular host operating systems.  In an access
concentrator network ([RFC4388]), a host receives a Router Advertisement
Message with no on-link prefix advertised.  The host incorrectly assumes
an invented prefix is on-link and performs address resolution when the
host should send all non-link-local traffic to a default router.
Neither the router nor any other host will respond to the address
resolution, preventing this host from sending IPv6 traffic.

NEW:

4.  Observed Incorrect Implementation Behavior

 One incorrect implementation behavior illustrates the severe
consequences when the IPv6 subnet model is not understood by the
implementers of several popular host operating systems.  In an access
concentrator network ([RFC4388]), a host receives a Router

 Advertisement Message with no on-link prefix advertised. The host
incorrectly assumes an invented prefix is on-link.   This invented
prefix typically is a /64 that was written by the developer of the API
as a "default" prefix length when a length isn't specified.  This   may
cause the API to seem to work in the  case of a network interface
initiating SLAAC, however it can cause connectivity  problems in NBMA
networks.  Having incorrectly assumed an invented prefix,  the host
performs address resolution when the host should send all
non-link-local traffic to a default router.  Neither the router nor  any
other host will respond to the address resolution, preventing this  host
from sending IPv6 traffic.

Thanks,

Hemant & Wes

---

From: Jari Arkko <[email-masked]>
Date: Fri, 05 Mar 2010 15:19:18 -0800

This example is better -- the description is now complete.

Jari

Hemant Singh (shemant) kirjoitti:

Jari,

Could
you please review the new text and see if the example is
able to explain what we meant by an “invented prefix” and let us
know if new text looks ok.

OLD:

4.
Observed Incorrect Implementation Behavior

One
incorrect implementation behavior illustrates the severe consequences
when the IPv6 subnet model is not understood by the implementers of
several
popular host operating systems.  In an access  concentrator network
([RFC4388]), a host receives a Router Advertisement Message with no
on-link
prefix advertised.  The host incorrectly assumes an invented prefix is
on-link and performs address resolution when the host should send all
non-link-local traffic to a default router.  Neither the router nor any
other host will respond to the address resolution, preventing this host
from sending
IPv6 traffic.

NEW:

4.
Observed Incorrect Implementation Behavior

One
incorrect implementation behavior illustrates the
severe consequences when the IPv6 subnet model is not understood by the
implementers
of several popular host operating systems.  In an access concentrator
network ([RFC4388]), a host receives a Router

Advertisement
Message with no on-link prefix advertised. The
host incorrectly assumes an invented prefix is on-link.   This
invented prefix typically is a /64 that was written by the developer of
the API
as a "default" prefix length when a length isn't specified.
This   may cause the API to seem to work in the  case of a network
interface initiating SLAAC, however it can cause connectivity  problems
in
NBMA networks.  Having incorrectly assumed an invented prefix,  the
host performs address resolution when the host should send all
non-link-local
traffic to a default router.  Neither the router nor  any other host
will respond to the address resolution, preventing this  host from
sending
IPv6 traffic.

Thanks,

Hemant
& Wes