PRISM based Transport: How Networks can Boost QoS for Advanced Video Services?

Abstract

Future applications and services will challenge the network infrastructure with unprecedented demands for high bandwidth, low latency and reliable communication. Moreover, popularity of applications requiring several function-alities such as control, telemetry, video and audio, each with its own requirements, is constantly increasing. For example, an interactive video service control requires low bandwidth and low latency while its 4K video flows require high bandwidth and moderate latency. Today's transport protocols do not address heterogeneous requirements. Instead, only bandwidth allocation is provided by congestion control schemes, which support up to two priorities. This limitation impairs Quality of Service (QoS) since it does not satisfy flow latency and bandwidth requirements in parallel. The overall QoS assurance is mainly handled by the application layer that usually reduce the video stream quality. We present PRISM, a new transport protocol on top of IP, which provides per flow granular and dynamic quality of service. PRISM applies state-of-the-art congestion control schemes (such as BBR, Proteus, Cubic) to allocate bandwidth. In addition, PRISM addresses reliability and latency requirements and couples flows from the same application together, enabling inter-flow synchronization. In experiments with a kernel implementation on emulated networks, dense camera grid applications' requirements were fulfilled by using PRISM, while the current transport protocols failed to satisfy all requirements. Furthermore, PRISM reduced establishment latency by a factor of up to 1000 compared to multiple TCP.