Seamless WiFi-roaming in IMS network

Over recent years, the explosion of radio access technologies and wireless networking devices has triggered the intensive use of nomadic computing. Mobile devices receive intermittent network access, and alternate between connected and disconnected states. However, today´s personal gadgets have more networking capabilities, wireless network coverage is becoming ubiquitous, and always-on IP-based services are now closer to reality. This paper shows a possible implementation of mobility in the IMS platform with using two wireless access points. A practical test was also done to investigate the quality of VoIP call as well as defects of this implementation.