  Nodes in an ad hoc wireless network incur certain costs for forwarding
packets since packet forwarding consumes the resources of the nodes. If the
nodes are rational, free packet forwarding by the nodes cannot be taken for
granted and incentive based protocols are required to stimulate cooperation
among the nodes. Existing incentive based approaches are based on the VCG
(Vickrey-Clarke-Groves) mechanism which leads to high levels of incentive
budgets and restricted applicability to only certain topologies of networks.
Moreover, the existing approaches have only focused on unicast and multicast.
Motivated by this, we propose an incentive based broadcast protocol that
satisfies Bayesian incentive compatibility and minimizes the incentive budgets
required by the individual nodes. The proposed protocol, which we call {\em
BIC-B} (Bayesian incentive compatible broadcast) protocol, also satisfies
budget balance. We also derive a necessary and sufficient condition for the
ex-post individual rationality of the BIC-B protocol. The {\em BIC-B} protocol
exhibits superior performance in comparison to a dominant strategy incentive
compatible broadcast protocol.
