Draft: draft-ietf-sipping-service-identification-00.txt Reviewer: Mahesh [mahesha@samsung.com] Review Date: 10/2/2007 Review Deadline: 10/31/2007 Status: Initial review Summary: This draft is on the right track but has open issues, described in the review. Starting with, let me discuss w.r.t the following definition from the draft "Service identification is the process of determining and/or signaling the specific use case that is driving the signaling being generated by a user agent." Here, if the signaling is really able to signal the Use-Case that is driving the Signaling then it would be Application Identification rather than just just Communication Service Identification because the Use-Case (defining theUser Experience) is modelled by the Application and not the Communication Service. But the draft title is "Identification of Communication Services". Signaling/determining a Communication Service does not neccessarily amount to determining/signalling the Use Case which is driving the signalling. Basically, it is unclear as to what is meant by "Service Identification" in this draft. So i tried to seek answer in Section 3 which tries to define "Service". Here, extract from RFC 4479(Presence Data Model) is referred to define a Service. " Each presentity has access to a number of services. Each of these represents a point of reachability for communications that can be used to interact with the user." There are two ways of interpreting this i1)"Point of reachability for Communications " can be WhiteBoard, Chess Game,Chatt Application which are all different instances of Interaction with the User. i2)"Point of reachability for Communications" can be Messaging Service, CS Telephony, PS Telephony which can be used by Applications such as Game,Instant Messenger,WhiteBoard etc to enable interaction with the User. It is more meaningful if it were (i1), so that the Presentity Info conveys exactly the kind of Use-Case/Interaction that a User can engage in with another User.Which Communication Service would be used to achive the Interaction/Use-Case may be irrelevant to the User. Also, later on in Section 3 of the draft i find the following: "Essentially, the service is the user-visible use case that is driving the behavior of the user-agents and servers in the SIP network." I'm still not able to understand "Service" and hence "Service Identification" from this draft because if "Service" is looked as as a user-visible use case then there is ambiguity in this draft as follows - The Title of the draft is "Identification of Communication Service", - however the term "Service" is being used to refer to the User Visible Usecase by statement ==> "Service Identification is the process of determining and/or signaling the specific use-case". - User Visible Use Case cannot be synonymous to Communication Service, in other words a Communication service may not be able to completely indicate/describe the User experience. For Example: by inidcating a Messaging Communication Service i cannot know if User is wants Gaming or Chatting.