Performance evaluation of IMS multimedia telephony over wireless LANs

Multimedia telephony over IP is a standardized IP multimedia subsystem (IMS) telephony service in release 7 of the third generation partnership project (3GPP), which is build on the IMS capabilities already provided in 3GPP Releases 5 and 6. In this paper we investigate the performance of IMS multimedia telephony service over WLAN access networks by the means of simulation using NS-2. The objective of this study is to evaluate the performance of multimedia telephony with IPSec tunnel in 3G-WLAN interworking architecture, and the maximum number of possible connections in a single 802.11 access point (AP) without degrading the required level of quality of service (QoS) for the multimedia traffic.