From Spectrum Agility to Network Agility: Proactive and Adaptive Reconfiguration for Reliable Communication in Tactical Networks

In tactical networks reliable communication is a vital military issue that needs to be resolved. A large number of research efforts are currently focused on providing radios with spectrum agility. However, in many cases, spectrum agility is not enough to achieve reliable communications in tactical networks. Instead, mission success often requires network agility -- cognition across the protocol layers for environmental awareness and autonomous reconfiguration -- which is still an unsolved challenge to our best knowledge, and needs to be addressed. Toward this, we have developed a proactive and adaptive cross-layer reconfiguration (PACR) framework for autonomous network adaptation through network monitoring, proactive prediction, network performance characterization, root-cause analysis, and cross-layer negotiation. Although PACR is generically applicable to any radio network, for validation it has been prototyped and demonstrated on two specific networks -- a commercial off-the-shelf (COTS) hardware testbed using IEEE 802.11 WiFi devices, and a military radio testbed using Warfighter Information Network-Tactical (WIN-T) Local Area Waveform (LAW) radios. Through tests and demonstrations, it has been shown that our solution provides cross-layer adaptation demonstrating spectrum as well as network agility, resulting in mission success through cognitive networking.