Subject: Re: ForCES transport requirements WAS (Re: Support for multicast in the ForCES protocol

From: "Khosravi, Hormuzd M" <[email-masked]>
Date: Tue, 25 Nov 2003 13:04:51 -0800

Steve,

The reason why the requirements are broad is cause we hope the ForCES
applicability and deployment will be broad. There are systems that will
use ForCES for several dozens or hundreds of FEs, there are also other
systems
that will use ForCES for say less than 20 FEs. Majority of the systems 
are of the latter type in the current market, just as majority of the
systems are of local scope (rack).

On the issue of scalability, there are no. numbers if you notice, it
just
relates to size of fields in the protocol messages. If you have a 10 bit
FE identifier, it satisfies this requirement (1K FEs).

On the issue of reliability & timeliness, this was beaten to death by
the 
Requirements Team. (Unfortunately, none of the emails were made public
since
one of the members objected to repeating the same arguments, which
seemed
like a valid point at that time. In retrospect, I wish they were made
public !)

We had received strong feedback from the IESG that our initial
reliability 
requirement was too weak and we should make it stronger cause its very 
important for any implementation. That's why you see 6 points and
atleast
one of them clearly states the importance of congestion control in the
Multihop scenario. Although, CC was also considered important in the
local
scope by many members, including the ADs this was arguable and hence not
made an explicit req for the local case. As regards timeliness, based on
Patrick's email clarifying this to the Requirements team it merely means
that a CE should know when a route was successfully downloaded on a FE,
(protocol response) and no one argued against that. I don't want to
quote
Patrick or any of the other members since this was private conversation,
however I see that this is being interpreted differently by different
people and I know Jamal has very different thoughts on this. If you take
timeliness to be a measure of routes/sec, it is very difficult to come
up with a number which will satisfy all systems. Atleast for routing
protocols,
as Joel pointed out this is very relaxed and can easily be in the order
of multiple seconds without causing any problems. (This is not to say
that
it should be in that order or that you cannot obtain hundred thousand
routes/sec using unicast)

We also received strong feedback from the Security Directorate, but I
wont
get into that right now :)

Hope this helps clarify the requirements,

regards
Hormuzd
-----Original Message-----
From: Forwarding and Control Element Separation
[mailto:[email-masked]] On Behalf Of Steven Blake
Sent: Monday, November 24, 2003 6:20 PM
To: [email-masked]
Subject: Re: [FORCES] ForCES transport requirements WAS (Re: Support for
multicast in the ForCES protocol

On Mon, 2003-11-24 at 15:35, Khosravi, Hormuzd M wrote:

> Hi Tal
>
> There is already a ForCES Requirements draft which has been approved
for
> RFC.
> Pls see...
http://www.ietf.org/internet-drafts/draft-ietf-forces-requirements-10.tx
> t
> This has a section on protocol requirements.

The problem with this draft (IMHO) is that it specifies a very broad
range of requirements, and it is not clear that they can all be
satisfied simultaneously using the same protocol techniques (which is
not to say that they cannot be satisfied using the same protocol, it
will however have to be very flexible).

Another problem is that there is no prioritization applied to the
requirements.  Therefore, different individuals prioritize them
independently based on their own priorities and product requirements.

I personally prioritize scalability and timeliness, and really have no
use for the security requirement, because I don't envision having to
deploy CE-FE communications over an open network.  Other opinions may
differ.

Regards,

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Steven L. Blake               <[email-masked]>
Ericsson IP Infrastructure                +1 919-472-9913

---

From: Alex Audu <[email-masked]>
Date: Wed, 26 Nov 2003 15:33:04 -0600

Hey Hormuzd,

Would you happen a copy of teh FORCES Minutes from IETF58?
I am not sure I've seen it mailed out. Please send me a copy if you
have it.

Thanks,
Alex.