“Always Best Packet Switching” for SIP services

We describe a distributed architecture for the provision of seamless and responsive mobile multimedia services. The architecture allows mobile applications to use concurrently all the wireless Network Interface Cards (NICs) a mobile terminal is equipped with. In particular, it enables the transmission of each datagram through the “most suitable” NIC among those available. We term this operating mode Always Best Packet Switching (ABPS). The ABPS architecture exploits a fixed proxy server, which acts as a relay for the mobile node and enables communications regardless of possible firewalls/NATs, together with a proxy client in the mobile node, responsible for maintaining a multi-path tunnel with the fixed proxy server. Experimental results show the effectiveness of our approach.