On behalf of Mr Voith

-----Original Message----- From: Thomas Voith [mailto:Thomas.Voith@alcatel.de] Sent: 01 October 2003 13:52 To: megaco@ietf.org; tsg16q3@itu.int Subject: Event descriptor handling for static logic interfaces like CAS

Dear list-members,

H.248.26 and in H.248.ICAS I miss a feature, which has been used already for On-Hook, Off-Hook the 'strict' parameter.

All interfaces, which have static states, should implement such a mechanism.

The problem is that the EventsDescriptor EventBufferDescriptor or an embedded EventsDescriptor may discard events, if the newly received or replacing Event Descriptor does not match the event.

In the Megaco Secnarios, always just the good case is shown.

e.g. a static interface with 4 logical incoming events ( S1,S2,S3,S4) would then set the EventsDescripror like:

MGC guess the MG is in state i1, no Notify will be sent by MG, when state of interface is still i1.

Events { S1{strict="exact"},S2{strict="state"},S3{strict="state"},S4{strict="state"} }

( Note: in case "state" is the default, then EventsDescriptor could be shorter)

The events descriptor remains active, after Notification is sent. The strict parameter avoids unnecessary Notifications for the already by MGC known state.

This mechanism would be very simple and avoids lost of any events, which is strong required for signalling interfaces on MG transferred via H.248 to an MGC.

For a better illustration I have attached a Excel-File containing a simple scenario.

So my question/proposal is:

- Is it possible to extend the existing static state interfacepackages like H.248.26 with this strict feature? - If not, can I get this functionality otherwise ?

Kind regards

Thomas Voith