I do not like the fact that suddenly the order of the elements in the OR
statement is important. Yes, compilers can optimize based onjthe order, but
the final result is indepdendent of the ordering. We need to think about
something different.
We still need a way for the peer to say that it does not understand a
capability and/or does not agree with any value proposed (and actually
conveys which value it would have agreed). It can be on the naswr message,
but we need a special notation for that.
regards,
Reinaldo
----- Original Message -----
From: "The Purple Streak, Hilarie Orman" <ho(_at_)alum(_dot_)mit(_dot_)edu>
To: "Penno, Reinaldo [BL60:0430:EXCH]"
<rpenno(_at_)americasm06(_dot_)nt(_dot_)com>
Cc: <ietf-openproxy(_at_)imc(_dot_)org>
Sent: Friday, April 18, 2003 2:17 PM
Subject: RE: Capability Negotiation for OCP
One of the PPP authors told me several years ago that PPP only used two
messages; perhaps it has changed. IKE does use just the two messages.
Preference of A1 over A2 is expressed as (A1 or A2); preference of A2
over
A1 is expressed as (A2 or A1), just like compilers do it.
OPES will have a rule compiler, it can certainly have a preference
compiler.
Hilarie
I do not follow you. PPP has configure-request, configure-response,
configure-nak and configure-rej to indicate that some capabilities
are
not-acceptable and others the peer proposes a differente value.
Anyway, I understand your proposal, but is awkard to put every single
acceptable value/range/strings for every capability. There might be
excessive overhead. On another point, how would you express
preference of A1
over A2? I guess ((A1) or A2)?
Alex,
In order to leverage cached negotiations, we can ask every
negotiation to
bear a identification number that is unique. Other negotiations can
refer to
it.
Regards,
Reinaldo
> -----Original Message-----
> From: The Purple Streak, Hilarie Orman
[mailto:ho(_at_)alum(_dot_)mit(_dot_)edu]
> Sent: Thursday, April 17, 2003 6:15 PM
> To: rousskov(_at_)measurement-factory(_dot_)com
> Cc: ietf-openproxy(_at_)imc(_dot_)org
> Subject: Re: Capability Negotiation for OCP
>
>
>
> PPP, IPSec and IKE use "offer, select". The trick is to
> spell out the complete set of selections at offer time.
> Don't say (A1 or A2) and (B1 or B2) if (A1 and B2) is not
> permitted - say instead
>
> { A2 and (B1 or B2) } or { A1 and B1}
>
> Hilarie
>