Subject: Re: Please consider last call on draft-ietf-forces-framework-02.t xt

From: "Syed, Jeelani" <[email-masked]>
Date: Fri, 11 Oct 2002 11:25:12 -0400

I agree, ForCES can define a standard for FE to announce its
capabilities to CE.

Regards,

-jeelani.sm

-----Original Message-----
From: Robert Haas [mailto:[email-masked]]
Sent: Friday, October 11, 2002 7:38 AM
To: [email-masked]
Subject: Re: Please consider last call on
draft-ietf-forces-framework-02.t xt

Lily, Jeelani,

"Syed, Jeelani" wrote [excerpt]:

> I see a drawback with first approach(CE offload is beyond ForCES), a
> vendor making a forwarding plane have to take care of all
> control plane vendors that are compatible with it for offloading.

"Yang, Lily L" wrote [excerpt]:

> Or, alternatively, we can take the physical boundary view and say "CE
> offload" is part of FE. Then ForCES is still exclusively used for CE-FE.
And
> as requirement draft already points out, FE model need to be able to
express
> such capability. Does it mean "OSPF Hello offload" is a functional block
> just like a "classifier" or "IPv4 Forwarder"?

Short answer: you are right.

Long answer:

The debate boils down to: what are today functions that we envision as "FE
functions" ? Is generating an ICMP error message something that an FE could
do ?
Obviously yes. Then the FE has to model this for the CE to be able to drive
this
function. In this case, the CE would simply tell the FE: "please take care
of
ICMP processing locally ( and don't bother me with this noise )".

The same argument holds for TCP termination or OSPF-Hellos state machine: to
ensure interoperability between FE vendors that incorporate such functions
and
CE vendors, we must make sure ForCES defines the appropriate semantics for
the
CE to drive these functions in the FEs.

So it's up to us to decide what we think are useful functions that FEs could
perform, and then ensure that ForCES has the semantics to allow the CE to
drive/control such functions. That was the reason why I suggested the
addition
of the "Off-loaded Functions" section into the requirements draft, and this
should be reflected into the framework draft somehow.

Regards,
--
Robert Haas
IBM Zurich Research Laboratory
Säumerstrasse 4
CH-8803 Rüschlikon/Switzerland
phone +41-1-724-8698  fax +41-1-724-8578  http://www.zurich.ibm.com/~rha