An Intelligent Tunneling Framework for Always Best Connected Support in Network Mobility (NEMO)

The Always Best Connected (ABC) vision has always been about IP-based architecture and multiple simultaneous access technologies which can provide wireless bandwidth aggregation and load-balancing features in fully overlapped coverage areas. This paper presents an intelligent tunneling framework, referred to as virtual SCTP tunneling, which enables the ABC vision in Network Mobility (NEMO). The virtual SCTP tunneling framework supports tunnels with multi-homed endpoints and can multiplex packets to multiple radio interfaces on a per-packet basis for better performance. Besides, it reduces the tunneling overhead over radio interfaces in heavy-load situation thanks to the predictive packet bundling feature. We carry out the simulation in the multi-homing context under ns2 and observe different metrics, e.g. throughput and packet loss rate seen by the wireless network, and the average end-to-end delay seen by Local Fixed Nodes. The performance of the proposed framework is compared with that of the existing per- flow forwarding which uses flow binding and IP tunneling. It is shown that the virtual SCTP tunneling is advantageous over the existing per-flow forwarding, especially in heavy-load situation.