In Camel Ph 3 funcions are almost same:
T-CSI
Possible TDPs: Terminating Attempt Authorised; $(begin$(CAMEL3$); Detection of unsuccessful call establishment (Called subscriber busy; not reachable; no answer) $(end$(CAMEL3$)
Possible DP criteria: basic service type, failure reason
VT-CSI:
Possible TDPs: Terminating Attempt Authorised; Detection of unsuccessful call establishment (Called subscriber busy; no answer)
Possible DP criteria: basic service type, failure reason
BUT in Camel Ph 2 only by VT-CSI you can detect and handle “Called subscriber busy; no answer”. In Cammel Ph 3 you have more flexibilty to decide where it is more suitable to handle IN service during MTC if it is in home network in GMSC or of it is in visited netw. of called subscriber.
To older question here-
SMS and IN – only in Camel Ph 3 and later
(SMS-CSI, SMS State models),
GPRS and IN – only in Camel Ph 3 and later (GPRS-CSI, GPRS state models)