A proposal for proxy-based mobility in WSNs

Inability to meet the key requirement of efficient mobility support is becoming a major impairment of wireless sensor network (WSN). Many critical WSN applications need not only reliability, but also the ability to adequately cope with the movement of nodes between different sub-networks. Despite the work of IETF's 6lowPAN WG and work on the use of MIPv6 (and many of its variants) in WSNs, no practical mobility support solution exists for this type of networks. In this paper we start by assessing the use of MIPv6 in WSNs, considering soft and hard handoff, showing that, although feasible in small networks, MIPv6 complexity leads to long handoff time and high energy consumption. In order to solve these problems, we propose a proxy-based mobility approach which, by relieving resource-constrained sensor nodes from heavy mobility management tasks, drastically reduces time and energy expenditure during handoff. The evaluation of both MIPv6 and the proposed solution is done by implementation and simulation, with a varying number of nodes, sinks and mobility strategies. (C) 2012 Elsevier B.V. All rights reserved.