Basavaraj Patil wrote:
On 3/14/07 12:04 PM, "ext James Carlson" <[EMAIL PROTECTED]> wrote:
Basavaraj Patil writes:
On 3/14/07 11:14 AM, "ext James Carlson" <[EMAIL PROTECTED]> wrote:
That issue is the exclusive use of IPv4 or IPv6 on Packet CS. Why
must it be exclusive? The first four bits of the datagram tell you
conclusively whether you're looking at IPv4 or IPv6, so why is strict
segregation needed?
Not sure I understand what you mean by segregation... The same packet CS is
used for IPv4 as well as IPv6. There are no separate CS' per se.
The classification rules segregate an IPv4 packet from an IPv6 packet and
map it to the appropriate transport connection (CID) over the air interface.
That's not what I meant.
A single CID using just Packet CS could handle both IPv4 and IPv6
traffic on the same interface.
You'd do this (on the receiver side) by looking at the first four bits
of the inbound IP datagram. They're '4', then it's IPv4. If they're
'6', then it's IPv6. If it's anything else, discard.
Okay.. I see what you mean. I don't really have a comment about it.
Sorry for interfering here, sorry if I misunderstand anything. Just one
thought: terminology.
I think this boils down again to that terminology issue, that longer
IEEE definition of what IETF calls "IPv6 CS". By IEEE, it's actually
"the IPv6 classifiers of the IP specific part of Packet CS". So this
document could be named "Prefix Assignment, Router Discovery, MTU and
IPv6 Addressing for the IPv6 classifiers of the IP specific part of the
Packet CS". Which doesn't make much sense, because one wouldn't run
Router Discovery over some classifiers.
We need that "IPv6 _over_ foo" tint. And these IPv6 classifiers aren't
_a_ foo.
Throughout the IEEE spec these IPv6 specific classifiers are mainly used
for PHS (packet header suppression) and recomposing. This is the most
use of these IPv6 classifiers.
In this context I'd comment on why IEEE is using this PHS, and not ROHC,
an IETF standardized protocol, for various link-layers. Or maybe any
other IETF-specified header compression (for ppp and for others).
I mean what if a Station uses ROHC and the link-layer does PHS - will
this result in inefficiency.
Just a thought on terminology...
Alex
______________________________________________________________________
This email has been scanned by the MessageLabs Email Security System.
For more information please visit http://www.messagelabs.com/email
______________________________________________________________________
--------------------------------------------------------------------
IETF IPv6 working group mailing list
ipv6@ietf.org
Administrative Requests: https://www1.ietf.org/mailman/listinfo/ipv6
--------------------------------------------------------------------
