Subject: RE: Higher level question about flow label

From: Thomas Eklund <[email-masked]>
Date: Sat, 18 Aug 2001 20:30:23 +0200

I vote for a semantics where you have MPLS or intserv style semantics and I
would also like a bit telling if the packet is encrypted or not.

[email-masked] 
-PS: Intserv is not 100% dead because there is an environment (wireless)
-where to get more bandwidth is really expensive (in Europe at least :-).
-PPS: there is another usage: flow-based switching for fast routing
-but I don't believe this really helps (petabit router vendors?)

--> No there is no need in term of a flow based switching fast routing since
the memory where you store the routing tables are so huge today. 512 K IPv4
prefixes could be stored in one CAM memory and usually you can use several
to obtain larger tables - all the CAM vendors support between 1 - 4 M IPv4
prefixes to be stored in their CAM and do one look up in a clock cycle. 

But many people are using flow to do traffic engneering and that's where I
belive the "mpls" op by hop semantic is needed. for the flow label. It would
also be easier to signal up to the routing protocls like IS-IS, OSPF. BGP
etc when a change occured.

-- thomas
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From: Brian E Carpenter <[email-masked]>
Date: Sun, 19 Aug 2001 14:30:03 -0500

Thomas,

How can you combine a routing handle usage with intserv usage?
These usages are totally disjoint. It's one or the other.

The historical fact (thanks to Frank Solensky for pointing this out in
private mail) is that we rejected the routing handle usage right at
the beginning of IPv6, even though some people disagreed and still regret
it. But we also moved the language about the flow label to an appendix
in RFC 2460, which means that many implementors seem to have ignored it.
I believe it is time to clean up that ambiguity.

BTW it's the presence of an ESP header that tells you if the packet is
encrypted. I don't see any need for a bit.

   Brian

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From: Jim Bound <[email-masked]>
Date: Sun, 19 Aug 2001 23:32:51 -0400 (EDT)

Brian,

Just to note.  You have 3 hard votes for b.

How long do we hold the voting booth open?  I suggest one month.

/jim