The paper investigates the capabilities of Parlay X Web Services for Policy and Charging Control (PCC) in managing all Internet-protocol-based multimedia networks (IMSs). PCC is one of the core features of evolved packet networks. It comprises flow-based charging including charging control and online credit control, gating control, and Quality of Service (QoS) control. Based on the analysis of requirements for PCC, the functionality for open access to QoS management and advanced charging is identified. Parlay X Web Services are evaluated for the support of PCC, and some enhancements are suggested. Implementation aspects are discussed, and Parlay X interfaces are mapped onto IMS control protocols. Use cases of Parlay X Web Services for PCC are presented. 1. Introduction IMS stands for internet protocol multimedia subsystem which is an architectural framework for service delivery in evolved packet networks. IMS enables various types of multimedia services based on access independency and IP connectivity . The main requirement for IMS in conjunction with IP connectivity access network (IP-CAN) is to provide quality of service. Quality of service (QoS) is used to differentiate multimedia offering from traditional Internet services, which in most cases do not provide QoS. In order to provide a mechanism for service-aware QoS control and coherent charging, the Policy and Charging Control architecture is standardized. The Policy and Charging Control (PCC) is a key concept in IMS architecture and it is designed to enable flow-based charging, including, for example, online credit control, as well as policy control, which includes support for service authorization and QoS management . In IMS, the user equipment negotiates with the network the session parameters by means of Session Initiation Protocol (SIP) signaling . The service-related information is delivered to PCC functional entities and is used to form authorized IP QoS data (e.g., maximum bandwidth and QoS class) and charging rules as well as user plane event reporting (e.g., bearer loss recovery, access network change, and out of credit) for any access network . To stimulate service provisioning and to allow applications outside of the network operator domain to invoke communication functions, an approach to opening the network interfaces is developed . The open access to network functions allows 3rd party applications to make use of network functionality and to receive information from the network through application programming interfaces (APIs). Parlay X Web Services are highly
F. Gouveia, S. Wahle, N. Blum, and T. Megedanz, “Cloud computing and EPC/IMS integration: new value-added services on demand,” in Proceedings of the 5th International ICST Mobile Multimedia Communications Conference, 2009.
S. Ouellette, L. Marchand, and S. Pierre, “A potential evolution of the policy and charging control/QoS architecture for the 3GPP IETF-based evolved packet core,” IEEE Communications Magazine, vol. 49, no. 5, pp. 231–239, 2011.
U. Iqbal, Y. Javed, S. Rehman, and A. Khanum, “SIP-based QoS management framework for IMS multimedia services,” International Journal of Computer Science and Network Security, vol. 10, no. 5, pp. 181–188, 2010.
Y. Wang, W. Liu, and W. Guo, “Architecture of IMS over WiMAX PCC and the QoS mechanism,” in Proceedings of the IET 3rd International Conference on Wireless, Mobile and Multimedia Networks (ICWMNN '10), pp. 159–162, 2010.
M. Jain and M. Prokopi, “The IMS 2.0 service architecture,” in Proceedings of the 2nd International Conference on Next Generation Mobile Applications, Services, and Technologies (NGMAST '08), pp. 3–9, September 2008.
J. Yang and H. Park, “A design of open service access gateway for converged Web service,” in Proceedings of the10th International Conference on Advanced Communication Technology, pp. 1807–1810, February 2008.
R. Good and N. Ventura, “Application driven policy based resource management for IP multimedia subsystems,” in Proceedings of the 5th International Conference on Testbeds and Research Infrastructures for the Development of Networks and Communities and Workshops (TridentCom '09), April 2009.
R. Good, F. C. De Gouveia, N. Ventura, and T. Magedanz, “Session-based end-to-end policy control in 3GPP evolved packet system,” International Journal of Communication Systems, vol. 23, no. 6-7, pp. 861–883, 2010.
F. Zhao, L. Jiang, and C. He, “Policy-based radio resource allocation for wireless mobile networks,” in Proceedings of the IEEE International Conference Neural Networks and Signal Processing (ICNNSP '08), pp. 476–481, June 2008.
S. G. Selvakumar, S. Paul Antony Xavier, and V. Balamurugan, “Policy based service provisioning system for WiMAX network: an approach,” in Proceedings of the International Conference on Signal Processing Communications and Networking (ICSCN '08), pp. 177–181, January 2008.
M. Elkotob, Autonomic resource management in IEEE 802.11 open access networks, Dissertation, Lules University of Technology, Lule？, Sweden, 2008, http://epubl.ltu.se/1402-1757/2008/38/LTU-LIC-0838-SE.pdf.
M. D. Stojanovic, S. V. B. Rakas, and V. S. Acimovic-Raspopovic, “End-to-end quality of service specification and mapping: he third party approach,” Computer Communications, vol. 33, no. 11, pp. 1354–1368, 2010.
F. Bormann, A. Braun, S. Flake, and J. Tacken, “Towards a policy and charging control architecture for online charging,” in Proceedings of the International Conference on Advanced Information Networking and Applications Workshops (WAINA '09), pp. 524–530, May 2009.
X. Duan, “Method for establishing Diameter session for packet flow based charging,” 2007, http://www.freshpatents.com/%20Method-for-establishing-diameter-session-for-packet-flow-based-charging-dt20070816ptan20070189297.php.