1. Diameter credit control application Diameter credit control application draft-hakala-diameter-credit-control-05.txt Harri Hakala Ericsson Leena Mattila Ericsson Jukka-Pekka Koskinen Nokia Marco Stura Nokia

2. Why New Diameter Application? During the last years the on-line accounting or so called pre-paid accounting has become very popular in mobile networks. - SS7 based protocols and IN (Intelligent Network) approach are used to realize pre-paid accounting. A new IP-based accounting protocol is urgently needed to support credit based accounting for Internet services Diameter base accounting or the current Diameter applications are not sufficient for real-time credit control. Diameter base accounting can be widely utilized. By accomplishing Diameter base accounting with bi-directional credit control functionality the on-line accounting support can be provided by the AAA infrastructure.

3. Overview of Application A general purpose real-time accounting protocol for various services/applications. Diameter accounting messages (ACR/ACA): - with new mandatory controlling AVPs - application defined state machines (session & event based state machines for client and server) - application specific fault handling On-line credit control with credit reservation (using session records) and operations: Price Enquiry, Balance Check, Direct Debiting and Refund (using event records) are supported

4. 3GPP Alignment The 3GPP TS 22.115 (service aspects; Charging and Billing) specifies charging guidelines for pre-paid services The 3GPP TS 32.225 (Rel. 5) specifies Diameter application for the IP Multimedia charging. This speciation is used both for off-line and on-line accounting. The 3GPP has aligned its IP multimedia on-line accounting functionality with the credit control draft.

5. What’s next ? The content of the credit control draft will be probably incorporated in the 3GPP TS 32.225 (as an Annex ?). New work item for the AAA-WG ?