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RE: [Sip] INFO considered harmful



The argument of "but I'm already holding a hammer and *want*
to treat everything like a nail!" comes up on about an annual
basis, and is rejected outright each time.

Just because you have a SIP stack in your application does
*not* mean that it is appropriate to use that stack for
all general network access. You're allowing laziness to
overwhelm good application design.

/a

> -----Original Message-----
> From: George Foti (LMC) [mailto:George.Foti@ericsson.ca]
> Sent: Thursday, January 02, 2003 12:55
> To: 'Michael Thomas'; Eric Burger
> Cc: Dean Willis; Jonathan Rosenberg; sip@ietf.org
> Subject: RE: [Sip] INFO considered harmful
> 
> 
> The application is SIP based, we dont need yet another 
> protocol to convey what needs to be conveyed e2e.
> No need to go around the bush.
> Lets find *real* arguments against using INFO for that 
> purpopse rather than philosphical  ones.
> 
> /gf
> 
> 
> 
> 
> -----Original Message-----
> From: Michael Thomas [mailto:mat@cisco.com]
> Sent: Thursday, January 02, 2003 12:53 PM
> To: Eric Burger
> Cc: Dean Willis; Jonathan Rosenberg; sip@ietf.org
> Subject: RE: [Sip] INFO considered harmful
> 
> 
> 
> I don't get it. If you want "100% application
> specific", why not pick an unused port and roll
> your own protocol? Then all of the crufty SIPism
> don't get in the way, and the hue and cry from
> this working group ceases immediately. Do the bits 
> on the wire keep warmer if they're dressed in SIP?
> 
>        Mike
> 
> Eric Burger writes:
>  > I fully agree with Dean on this one.
>  > 
>  > One point to consider (I'm on the fence on this one) is 
> whether we would say that INFO is 100% application-specific.  
> That is, the WG will not publish standard body types.
>  > 
>  > A reason for doing that is to let people know that INFO 
> really is just, as Dean points out, 
> application-to-application communication.  If you want 
> applications to interoperate, take it either to an 
> Application Area WG or take it outside the IETF.
>  > 
>  > One reason to not do this is SIP-T should use a method 
> other than INFO.  That said, I don't think there are that 
> many SIP-T implementations extant.
>  > 
>  > 
>  > > -----Original Message-----
>  > > From: Dean Willis [mailto:dean.willis@softarmor.com]
>  > > Sent: Tuesday, December 31, 2002 1:48 AM
>  > > To: Jonathan Rosenberg; Orit Levin
>  > > Cc: sip@ietf.org
>  > > Subject: Re: [Sip] INFO considered harmful
>  > > 
>  > > 
>  > > At 12:48 AM 12/31/2002 -0500, Jonathan Rosenberg wrote:
>  > > >Orit Levin wrote:
>  > > >>>The big huge difference I have been trying to point out is 
>  > > that EVENTS
>  > > >>>DEFINES SEMANTICS, whereas INFO doesnt.
>  > > >>>MIME provides semantics and syntax that are independent of 
>  > > the type.
>  > > >>>SIP events provides semantics and syntax that are 
>  > > independent of the
>  > > >>>package.
>  > > >>>INFO provides nothing.
>  > > >>
>  > > >>INFO provides "minimal" but very important semantics: 
>  > > asynchronous data
>  > > >>reliably follows the established SIP path.
>  > > >
>  > > >Huh?
>  > > >
>  > > >Every new SIP method is reliable, it inherits the SIP 
>  > > transaction state 
>  > > >machine for non-invite. Follows the established path? Every 
>  > > in-dialog 
>  > > >method would have this property, it is method independent. 
>  > > >Asynchronous?  You can send any method at any time.
>  > > >
>  > > >Thus, nothing you have pointed out above is different 
>  > > between INFO and any 
>  > > >other new method we might introduce.
>  > > 
>  > > I think the key point is that there is a difference 
> between transport 
>  > > protocol semantic and application semantic. The transport 
>  > > protocol semantic 
>  > > expressed in INFO is "Here is some data that will be used by the 
>  > > application. It is not important to the transport protocol, 
>  > > except that the 
>  > > transport protocol is expected to deliver it reliably". INFO 
>  > > says NOTHING 
>  > > about the APPLICATION level semantic -- that's up to what 
>  > > goes IN the INFO 
>  > > payloads. The question is -- do we try to rigidly define 
>  > > application-level 
>  > > semantics here? Do we define that there ARE no such 
>  > > applications possible? 
>  > > Or do we design a framework by which application-level 
>  > > semantics can be 
>  > > expressed outside of the protocol definition?
>  > > 
>  > > And as for "Just add another method to your SIP stack". Let's 
>  > > say I have a 
>  > > mobile phone and the SIP stack is burned into ROM and 
> exposes only a 
>  > > simplistic transactional API. This is only likely to 
> happen, oh, 100 
>  > > million times or so over the next two years . . .  Now, just 
>  > > exactly how is 
>  > > my BREW or JTME application going to go about extending the 
>  > > SIP stack to 
>  > > support another method? Will the evil wireless operator 
>  > > networks even pass 
>  > > another method? Neither is happening anytime soon, I think . . .
>  > > 
>  > > --
>  > > Dean
>  > > 
>  > > 
>  > > _______________________________________________
>  > > Sip mailing list  https://www1.ietf.org/mailman/listinfo/sip
>  > > This list is for NEW development of the core SIP Protocol
>  > > Use sip-implementors@cs.columbia.edu for questions on current sip
>  > > Use sipping@ietf.org for new developments on the 
> application of sip
>  > > 
>  > _______________________________________________
>  > Sip mailing list  https://www1.ietf.org/mailman/listinfo/sip
>  > This list is for NEW development of the core SIP Protocol
>  > Use sip-implementors@cs.columbia.edu for questions on current sip
>  > Use sipping@ietf.org for new developments on the application of sip
> _______________________________________________
> Sip mailing list  https://www1.ietf.org/mailman/listinfo/sip
> This list is for NEW development of the core SIP Protocol
> Use sip-implementors@cs.columbia.edu for questions on current sip
> Use sipping@ietf.org for new developments on the application of sip
> _______________________________________________
> Sip mailing list  https://www1.ietf.org/mailman/listinfo/sip
> This list is for NEW development of the core SIP Protocol
> Use sip-implementors@cs.columbia.edu for questions on current sip
> Use sipping@ietf.org for new developments on the application of sip
> 
_______________________________________________
Sip mailing list  https://www1.ietf.org/mailman/listinfo/sip
This list is for NEW development of the core SIP Protocol
Use sip-implementors@cs.columbia.edu for questions on current sip
Use sipping@ietf.org for new developments on the application of sip