Re: prefixlen of IPv6 over PPP

[Nagae Hidetake <nagae%eagan.jp@localhost>]

From: "Brian A. Seklecki" <seklecki%noc.cfi.pgh.pa.us@localhost>
Subject: Re: prefixlen of IPv6 over PPP
Date: Fri, 06 Nov 2009 11:43:41 -0500

> Very curious.  check some RFCs, or check an XP box.  What is RTADV
> giving them and what are they accepting?
> 
> Assigning a /128 to an v6 PPP interface is like assiging a /32 to an
> IPv4 (/31 is...maybe known to work in some exotic platforms, but..)

In Section 4.1 (Interface Identifier) of RFC 5072 (IP Version 6 over PPP):

  This Configuration Option provides a way to negotiate a unique, 64-
  bit interface identifier to be used for the address autoconfiguration
  [3] at the local end of the link (see Section 5).

In Section 5.3 (Creation of Link-Local Addresses) of RFC 4862 (IPv6
Stateless Address Autoconfiguration):

  If the sum of the link-local prefix length and N is larger than 128,
  autoconfiguration fails and manual configuration is required.


So I think prefixlen should be 64, but I'm not sure...


RA is proposing 64-bit prefix.
Vista box accepts it.

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Nagae Hidetake          nagae%eagan.jp@localhost
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