Efficient and scalable charging systems for IP multimedia networks

The advent of IP communications challenged the use of legacy charging methods. Moreover, the diversity of Internet applications complicates the deployment of charging schemes in converged networks. Charging requires the collection of accounting information of resource usage, a process that consumes system resources that are needed for service delivery. Flat rate charging is popular on the Internet; it is associated with best-effort transport of traffic. Through QoS provisioning, operators can differentiate the treatment of different applications, to meet application requirements and diverse user preferences. Usage and QoS based charging is used with QoS provisioning schemes. Scalable accounting for multimedia service provisioning requires management planning to utilize simpler accounting mechanisms that cater for the QoS levels, data volumes and duration of usage. In this paper we explore mechanisms for achieving scalable charging for IP based multimedia communications. We present charging performance results from an IMS testbed based on the UCT SDP.