1. A dynamic QoS control scheme for services based on RACF
Oct. 2006
TTC

2. In the last Study Group 13 meeting in Geneva, July 17-28, 2006
Introduction
In the last Study Group 13 meeting in Geneva, July 17-28, 2006
Two contributions [1-2] regarding a dynamic QoS control scheme based on RTP/RTCP were discussed at Q.4/13
The work item is on dynamic QoS control based on RTCP reports (with possible extensions) or similar mechanisms in the network as related to RACF and Y.mpm.
We describe a session observation method and a system configuration for a dynamic QoS control scheme based on RACF.
[1] H. YAMADA and S. UEMURA, “Proposal for initiation of a study of the quality control
scheme for service sessions based on (S/BC) functions,” SG13 Delayed Contribution D581,
Geneva, July 2006.
[2] S. UEMURA and H. YAMADA, “A QoS notification scheme for end-to-end service session
quality control,” SG13 Delayed Contribution D583, Geneva, July 2006.

3. Generic system configuration
A dynamic QoS control scheme based on RTP/RTCP
The configuration of the quality control schemes for admission control of NGN terminals and the control of aggregated sessions among NGN terminal.

4. Observation of RTP streams using RTCP
Rec. P.564:
Conformance testing for narrowband voice over IP transmission quality
assessment models
Several operation scenarios for monitoring session performance are discussed in ITU-T SG12 and indicated in Table 1/Rec. P.564. Especially, in Mode A, the dynamic operation uses information from RTCP-XR packets.

5. Functionalities of PD-FE and TRC-FE
PD-FE (Policy Decision Functional Entity)
The PD-FE handles the QoS resource requests received from the SCF via the Rs reference point or from PE-FE via the Rw reference point.
TRC-FE (Transport Resource Control Functional Entity)
The TRC-FE is responsible for transport technology dependent resource control such as resource status monitoring and network information collection.

6. Multi-RTCP scheme
The Multi-RTCP scheme supports the scheme for reporting a quality condition of a portion of the end-to-end IP networks basis such as the FMC networks.
Fig.1-Configuration of the Multi-RTCP scheme in FMC networks
Fig.3- Initiation of Multi-RTCP scheme
Fig.2- Relay of Extra RTCP RR

7. Evaluation of the Multi-RTCP scheme

8. Evaluation of the Multi-RTCP scheme
The RTP clients which use the QoS information of the congested network can adjust the sending bit rate appropriately.
The RTT information of entire network A and B is not sufficient to understand the reason for the fluctuation of RTT.

9. conclusions
We have offered the following propositions for developing a quality control scheme for service sessions based on RACF.
The focus and first priority of study should be on the formulation of functionalities of the PD-FE and TRC-FE for a dynamic QoS control scheme.
2. Study should be initiated on a practical dynamic QoS control scheme based on RTCP reports (with possible extensions).
3. Actions should be conducted to provide solutions to QoS requirements and QoS metrics desirable to the control scheme need to be studied.

10. References
[1] H. Schulzrinne, S. Casner, R. Frederick and V. Jacobson, “RTP: A Transport Protocol for Real-Time Applications,” IETF RFC 3550, July 2003.
[2] ITU-T Recommendation P.564, “Conformance testing for narrowband voice over IP transmission quality assessment models,” International Telecommunication Union, July 2006.
[3] T. Friedman, R. Caceres, A. Clark, “RTP Control Protocol Extended Reports (RTCP XR),” IETF RFC 3611, November 2003.
[4] ITU-T Recommendation P.862, “PESQ an objective method for end-to-end speech quality assessment of narrowband telephone networks and speech codecs,” International Telecommunication Union, February 2001.
[5] ETSI TS , “Digital cellular telecommunications system (Phase 2+); Adaptive Multi-Rate (AMR) speech transcoding(GSM version Release 1998),” European Telecommunications Standards Institute, April 2000.
[6] J. Sjoberg, M. Westerlund, A. Lakaniemi, Q. Xie, “Real-Time Transport Protocol (RTP) Payload Format and File Storage Format for the Adaptive Multi-Rate (AMR) and Adaptive Multi-Rate Wideband (AMR-WB) Audio Codecs,” June 2002.