Planning the Mobility of Routing Ferries for Intermittently Connected Mobile Networks

The intermittent connectivity is very familiar in mobile wireless networks because of the constraint of communication range, interfere and attenuation of the signal etc. Therefore, store-carry-forward becomes an important routing mode in the intermittently connected mobile networks (ICMNs), and some node must carry the message when the wireless communications are unavailable. Selection of carriers now becomes the most important parts in the routing of ICMNs, and the selections will influence directly the performance of routing such as the delivery ratio and routing delay. The scheme that normal mobile nodes take the role of carrying is based on the assumption that all mobile nodes handheld by human beings are cooperative which is unpractical because the carrying need consume the network resource and energy. Furthermore, the routing performance can not be guaranteed as a result of the uncertainty of the carriers' movement even if such assumption is satisfied. Therefore, a routing scheme based on the mobile routing ferry for ICMNs is firstly provided in this paper, where the routing ferries are mobile infrastructural nodes used to carry the message between source nodes and destination nodes. Routing ferries are cooperative in nature and the elaborate planning of ferries' movement will guarantee the routing performance. This paper provides the structure of the routing ferry for ICMNs, formally describes the problem of the planning of routing ferries based on graph, and provides a dynamic programming algorithm to plan the movement of the routing ferries. The experiments driven by the trace data show that the planning of mobile routing ferry provided in this paper can achieve good effects for performance guaranteed routing in ICMNs.