PeerTalk: A Push-to-Talk and Instant Messaging Service for Tactical Networks

Mobile multi-service peer-to-peer architectures allow the establishment of multimedia sessions, like Push-to-Talk (PTT), Push-to-Talk over Cellular (PoC) and Instant Messaging (IM), between a group of mobile peers with limited or no use of centralized servers. PTT enables several users on different peers to speak with each other while using a single, half-duplex, communication channel, such that only one user speaks at a time while all other users listen. Enabling PTT on this type of architecture for tactical networks provides reduced transmission delay, increased robustness and higher fault tolerance compared to hybrid and pure client-server architectures. There are many challenges facing the implementation of PTT/IM on tactical networks, given the intrinsic nature of unreliable and transiently connected communications that is typical of these environments. This paper presents a new approach called PeerTalk, a cross-platform service operating on a mobile multi-service peer-to-peer architecture enabling a robust, distributed PTT and IM service. The proposed approach is designed to operate efficiently and resiliently over cellular and Wi-Fi tactical networks.