To provide good QoS to calls and maximize network resource utilization in IP Telephony networks, it is necessary to design a differentiated service architecture that includes call admission and call redirection policies. In this work, we first study a call admission policy based on congestion sensitive pricing. The scheme uses congestion pricing to preferentially admit users who place a higher value on making a call while simultaneously maintaining a high utilization of IP Telephony Gateway (ITG) voice ports. Second, we design a call redirection policy to select the best ITG to serve the call. The policy balances load to improve network efficiency and incorporates QoS sensitivity to improve call quality. We present a performance study of the call admission and the redirection policies using both analytical and simulation models. The techniques studied in this paper can be combined into a single resource management solution that can improve network resource utilization, provide differentiated service, and maximize provider revenue.
1Professor, UC Davis