A Full-Distributed Architecture for PoC Application in Data Packet Voice Communication

Push-to-Talk over Cellular (PoC) is a "walkie-talkie" like voice communication service over mobile wireless networks, based on Voice over IP (VoIP) technology. The traditional PoC defined in the Open Mobile Alliance (OMA) specification is a centralized architecture. In this architecture, servers need to be deployed for the PoC service to work and be widely available, presenting a substantial cost to ISPs. Meanwhile, the problem of network congestion and one point failure existing in the centralized architecture may degrade system performance and cause the failure of an entire system. In addition, the traditional floor control based on the centralized architecture, also suffers from the drawbacks of using a centralized controller. In this article, we propose a full-distributed architecture for PoC application (FDPoC) in data packet voice communication. In the full-distributed architecture, we propose an ALM-based distributed data packet transmission mechanism and a distributed floor control (DFC) algorithm to alleviate the above issues. In terms of average end to end delay, average max end to end delay and average floor determination delay, the performance of the proposed FDPoC and DFC algorithm are investigated through our analytical model.