Subject: RE: [PWE3] MPLS PID

From: Shahram Davari <[email-masked]>
Date: Wed, 26 Mar 2003 12:34:28 -0800

>>
>>1) ECMP could use only label hashing and not hash IP header.
>
>         This is unrealistic. Lots of vendors hash on both,
>one or the other.  Lets not go down the road of trying
>to mandate how ECMP works again. We went down that
>road in MPLS and the response was clear.

Hashing on IP header is not part of any IETF standard, and I am not sure all future IETF
standards should be based on supporting non-standard proprietary implementations. if one likes
to still hash IP header, then he could define a proper protocol mux header and use it all the time.

>
>>2) OAM flows could use IPv4/V6 null or MPLS Alert label
>
>         Encased in the PW or just as a label stack?

Tunnel Label - PW label - IPV4/6 explicit null. And hash only up to 2nd label.

>
>>3) Netmanagment could identify the flow at the ingress.
>
>         What about the egress?

Also egress could identify the flow from bottom label.

-Shahram

>         --Tom
>>-Shahram

---

From: George Swallow <[email-masked]>
Date: Wed, 26 Mar 2003 17:05:00 -0500

Shahram -

> Hashing on IP header is not part of any IETF standard, and I am not
> sure all future IETF standards should be based on supporting
> non-standard proprietary implementations. if one likes to still hash
> IP header, then he could define a proper protocol mux header and use
> it all the time.

There is a long history of standards bodies respecting equipment that
has already been fielded.  In this case we are talking about 100s of
thousands of units.   It was the IETF that chose to define the MPLS
encapsulation without a PID.  That's water under the bridge.  Now we
have to deal with it.

...George

==================================================================
George Swallow       Cisco Systems                  (978) 497-8143
                     250 Apollo Drive
                     Chelmsford, Ma 01824

---

From: Curtis Villamizar <[email-masked]>
Date: Wed, 26 Mar 2003 17:04:37 -0500

In message <[email-masked].
ca>, Shahram Davari writes:
> sure all fu ture IETF standards should be based on supporting
> non-standard proprietary implementation s. if one likes to still hash

You keep repeating this "non-standard proprietary" diatribe despite
being corrected.

src/dst based hash has been used for almost 15 years now.  In 1988 you
might have been more justified in calling it "non-standard
proprietary" but not in 2003.

It is documented in RFC 2991.

  2991 Multipath Issues in Unicast and Multicast Next-Hop Selection. D.
       Thaler, C. Hopps. November 2000. (Format: TXT=17796 bytes) (Status:
       INFORMATIONAL)

This makes it far from proprietary and the fact that the document as
informational does not make it non-standard.  It is not mandated by
any specific protocol but it is widely implemented and deployed.

src/dst hash based load split is widely deployed in numerous protocol
and considered important by many ISPs.

So please stop making the "non-standard proprietary" accusation unless
you want to be known as someone who persistantly ignores the facts.

Curtis