The focus of my research is on security in wireless lightweight ad hoc networks. So far, much research has been concentrated primarily on making ad hoc networks feasible and useful and not on issues of security. However, ad hoc networks are highly vulnerable to attacks. In my research, I will present the requirements of making an ad hoc network secure and scalable, and also provide solutions as to how to authenticate the identity of the nodes by only adding one authentication bit to each packet. This will dramatically reduce the bandwidth and power consumption in the ad hoc network.