IPv6 routing issues
bound@zk3.dec.com
bound@zk3.dec.com
Wed, 09 Oct 96 18:09:50 -0400
% Well we have a pretty good OSPFv6 spec out there now and I am hoping Rob
% Coltun does an implementation. So I am not concerned if it later has to
% be updated to v3.
>I do not understand your comment.
>By the way, OSPF for IPv6 == OSPFv3.
Sorry. I thought OSPFv3 was more than the attached abstract?
If its OSPFv3 is in fact the work going for the attached abstract yours
is the first mail I have seen referncing it as OSPFv3. I reference it
as OSPFv6. ?????
---------------------------------------------------
"OSPF for IPv6", R. Coltun, D. Ferguson, J. Moy,, 06/10/1996,
<draft-ietf-ospf-ospfv6-02.txt>
This document describes the modifications to OSPF to support version 6
of the Internet Protocol (IPv6). The fundamental mechanisms of OSPF
(flooding, DR election, area support, SPF calculations, etc.) remain
unchanged. However, some changes have been necessary, either due to
changes in protocol semantics between IPv4 and IPv6, or simply to
handle the increased address size of IPv6.
Changes between OSPF for IPv4 and this document include the following.
Addressing semantics have been removed from OSPF packets and the basic
LSAs. New LSAs have been created to carry IPv6 addresses and prefixes.
OSPF now runs on a per-link basis, instead of on a per-IP-subnet basis.
Flooding scope for LSAs has been generalized. Authentication has been
removed from the OSPF protocol itself, instead relying on IPv6's
Authentication Header and Encapsulating Security Payload. Most
packets in OSPF for IPv6 are almost as compact as those in OSPF for
IPv4, even with the larger IPv6 addresses. Most field- and packet-size
limitations present in OSPF for IPv4 have been relaxed. In addition,
option handling has been made more flexible.
------------------------------------------------------
% As far as I-IS-IS that is a nice to have but IPv4 and IPv6 routing is a
% bit different than tunneling IP in CLNP or the other way around.
End of excerpt from bound@zk3.dec.com
>I did not mention I-ISIS in my note (I was discussing integrated routing for
>OSPFv3), though I do find your comments interesting in the context of the
>Digital entry on the IPng web site, thinking particularly where it says
>(quoted directly):
>
> "In addition, Digital intends to implement IPv6 in the
> Integrated IS-IS routing protocol to allow an integrated approach
> to routing of IPv4, IPv6, DECnet and OSI."
This is from your previous mail.
& Similarly, my (possibly outdated) understanding has been that the OSPFv3 spec
&was still evolving. For example, there were some unresolved discussions about
&whether the OSPFv3 spec could be changed to permit OSPFv3 to route both IPv4
&and IPv6 (analagous to how Integrated ISIS works). The feature of "integrated
&routing" is one that our customers are clearly asking for. Many customer
&sites view integrated routing as critical to their ability to transition from
&IPv4-only to IPv4+IPv6 routing.
I see the confusion...
I was referencing your analogy above of how I-IS-IS works and its not worth
doing on a router that only supports IPv4 or even a Host based Router.
As far as the WWW Page thats a true statement to support existing
customers to get to IPv6 from an environment where IPv4, DECnet, and CLNP
are routed on the backbone. Note the WWW page said Digital would implement
it not that we would go to standards bodies to propose the change. Though
that may happen. My comment was for the majority of nodes on the Internet
that are using only IPv4 developing a full blown I-IS-IS protocol for
IPv4/IPv6 seems like overkill to me.
Also I am mostly here as an individual (I cannot deny who pays for me to
spend my time on this) and if Digital wants to build I-IS-IS extensions
in the IETF I may disagree with my own fellow employees at Digital and
at the IETF. I don't see the need. Now as always I am always open to
listening and changing my mind.
thanks
/jim