  In wireless packet-forwarding networks with selfish nodes, applications of a
repeated game can induce the nodes to forward each others' packets, so that the
network performance can be improved. However, the nodes on the boundary of such
networks cannot benefit from this strategy, as the other nodes do not depend on
them. This problem is sometimes known as the curse of the boundary nodes. To
overcome this problem, an approach based on coalition games is proposed, in
which the boundary nodes can use cooperative transmission to help the backbone
nodes in the middle of the network. In return, the backbone nodes are willing
to forward the boundary nodes' packets. The stability of the coalitions is
studied using the concept of a core. Then two types of fairness, namely, the
min-max fairness using nucleolus and the average fairness using the Shapley
function are investigated. Finally, a protocol is designed using both repeated
games and coalition games. Simulation results show how boundary nodes and
backbone nodes form coalitions together according to different fairness
criteria. The proposed protocol can improve the network connectivity by about
50%, compared with pure repeated game schemes.
