A comparative assessment of routing for mobile networks

Wireless mobile devices are becoming increasingly prevalent in society. As a result, aggregation of network connectivity through the use of mobile networks is becoming increasingly relevant to service providers as well as for mobile users. The current approach being pursued within the IETF Mobile Extensions for IPv6 (MEXT) WG, is based on the Network Mobility (NEMO) architecture. NEMO uses IP-in-IP tunnelling for providing mobile network capability on an existing IPv6 network. This approach can result in non-optimal routing between source and destination nodes. Other proposals such as OptiNets extend NEMO and try to address issues such as sub-optimal routing. There are alternative approaches also being proposed, such as the Identifier Locator Network Protocol (ILNPv6), which is based on the use of naming, to enable a flexible and integrated mobile network capability based on IPv6.We have conducted a comparative analysis of the cost of providing optimal routing, in terms of packet and bandwidth overhead, based on an emulation, using data from the London Circle Line metropolitan railway as a scenario. Our analysis shows that these different approaches to mobility offer significantly different performance trade-offs in routing for mobile networks, depending on the constraints of the network scenario.