Subject: RE: [midcom] R75

From: "Reinaldo Penno" <[email-masked]>
Date: Wed, 17 Oct 2001 14:10:43 -0700

I would like more clarification on that before deleting.

Are we saying that in the case of, for instance BGP, where ingress and
egress traffic can take different paths and pass through different MBs,
MIDCOM will not work OR that it will work on any topology but IF routing
changes then it might fails?

If we are somewhat restricting MIDCOM usage to certain topologies or routing
configurations I disagree.

thanks,

> -----Original Message-----
> From: Melinda Shore [mailto:[email-masked]]
> Sent: Wednesday, October 17, 2001 11:30 AM
> To: [email-masked]
> Subject: [midcom] R75
> 
> 
> The text of R75 is this:
>  R75: The Midcom Protocol must produce robust operation even when
>         routing changes such that traffic from a particular end system
>         passes through a different middlebox.  (Huitema)
> 
> 	   Eliot Lear says "this takes too much state".
> 
> I'm with Eliot on this, but even if I weren't this really is
> too closely related to the topology issue to be able to resolve
> now.  I'm proposing deleting R75.
> 
> Melinda
> 
> 
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> http://www1.ietf.org/mailman/listinfo/midcom
>

---

From: "Eliot Lear" <[email-masked]>
Date: Wed, 17 Oct 2001 14:29:33 -0700

If one takes R75 at face value it REQUIRES state to be shared amongst
middle boxes.  And if we thought we had a tough job before, this would
really put the nail in the coffin.  NATs aren't required to share state.
Firewalls aren't required to share state.  Let's not do things that make
it impossible for middle boxes to share state, but then let's not
require it either.

---

From: Keith Moore <[email-masked]>
Date: Wed, 17 Oct 2001 18:20:26 -0400

> Are we saying that in the case of, for instance BGP, where ingress and egress
> traffic can take different paths and pass through different MBs, MIDCOM will
> not work OR that it will work on any topology but IF routing changes then it
> might fails?

of course!

it's clearly unreasonable to expect midcom to fix this.  midcom exists
for the very purpose of allowing (and manipulating) state in NATs and
firewalls.  loss of robustness is an inherent consequence of a decision 
to put devices with unrecoverable state in the network.  

Keith