This chapter explains the network layer effects of denial of service (DoS) in 5G wireless networks. DoS attacks by malicious nodes have mostly been researched in terms of their effect on the physical layer for the good nodes or in terms of loss of services for the good nodes. The chapter presents an analysis to study the connectivity of ad hoc 5G networks under DoS. The DoS attack that 5G networks are susceptible to, is similar to primary user emulation attack, introduced in, unique to cognitive radio enabled dynamic spectrum access networks. Since the primary function of the network layer is the routing of data packets to their destinations, a basic requirement for efficient network layer performance is the connectivity of the underlying ad hoc network graph. The distributed protocol reduced the probability of the network becoming disconnected by 31% to two orders of magnitude.