[Sipping] draft-watson-sipping-req-history-01

[frank.derks@philips.com]

Having read this read this draft, I was wondering why the authors have not
produced a new version. Because, as indicated in the draft, SIP currently 
does not have certain potentially useful"notification mechanisms" (and I 
am not referring to SIP NOTIFY). 

Notifications that help the participants involved in session establishment 
to take action based on "why" a request arrived and "from where" it arrived,
could greatly enhance the services offered.

Take the following example. When Alice calls Bob and is diverted to Carol,
it might be useful (depending on what you want to do) to have:

- a way to inform Alice and Carol about what't going on. I.e. that the call
  is being diverted and why it is being diverted.
- a way to inform Carol about the party that was originally called and the
  party that is diverting the call
- preventing this information from being presented
- etc.

There are many more possibilities. These issues surfaced when we were 
trying to look at some interworking scenarios between QSIG supplementary
services and SIP. The lack of this sort of functionality would reduce 
the QSIG functionality in an interworking scenarion

Not surprising, this type of notifications, is also useful in a "pure"
SIP environment. Which sort of brings me back to my original question. 

I support that the SIPPING and SIP groups should probably make this into
an item to be addressed. 

Any other views?



Regards,

Frank