The network can be a powerful platform at the core of an advanced mobility security architecture. There are several unique benefits of using the network to provide security. Virtually all traffic – good and bad – traverses the network. Also, the network sees traffic from many places and can correlate data to find problems. The network has unlimited battery and processing power, is independent of end devices, and cannot easily be circumvented (as can software on devices). AT&T is investing significant research resources in order to realize the vision of the network as a mobility security platform. Project Marconi is instrumenting the mobility network to be able to detect and act upon malicious traffic. Project Saturn / Smart Mobile Computing will provide a more secure environment for mobile devices that today can bypass the protection of a security perimeter. And, a new host-assisted, network-based architecture will enable fine grained detection, mitigation, and recovery on mobile devices. Current research challenges include determining the theoretical subset of attacks that can be detected in the network, and defining algorithms to do this at an extreme scale in near real time.