Application Layer Congestion Control for Network-Aware Telehaptic Communication

In a real-world network, shared by several users, telehaptic applications involving delay-sensitive multimedia communication between remote locations demand distinct Quality of Service (QoS) guarantees for different media components. These QoS constraints pose a variety of challenges, especially when the network cross-traffic is unknown and time-varying. In this work, we propose an application layer congestion control protocol for telehaptic applications operating over shared networks, termed as dynamic packetization module (DPM). DPM is a lossless, network-aware protocol which tunes the telehaptic packetization rate based on the level of congestion in the network. To monitor the network congestion, we devise a novel network feedback module, which communicates the end-to-end delays encountered by the telehaptic packets to the respective transmitters, with negligible overhead. Via extensive simulations, we show that DPM meets the QoS requirements of telehaptic applications over a wide range of network cross-traffic conditions. We also report the qualitative results of a real-time telepottery experiment with several human subjects, which reveal that DPM preserves the quality of telehaptic activity even under heavily congested network scenarios. Finally, we compare the performance of DPM with existing telehaptic communication protocols, and conclude that DPM outperforms other techniques.