In this paper we investigate the problem of maintaining connectivity
under jamming in multihop ad hoc wireless networks. Connectivity is
measured using a connectivity index, which indicates the probability
that there exists a path between two nodes. We first show that
connectivity can be drastically reduced with a relatively small number
of jammers. We show that using sectored antennas can maintain
connectivity in the presence of a significantly higher number of
jammers at the expense of higher average number of hops. Finally, we
show that mobility allows further resiliency to jamming.