Systems Research Group

Network Supports for Streaming Video Quality of Experience

How can I prevent my child from taking receiving HD video on their phone, while I’m stuck watching grainy images on our 50 inch TV?” This is an increasingly common type of complaint among subscribers of streaming video services. Nonetheless, content services such as Netflix and YouTube are the wrong target for such complaints. So too, the home or mobile broadband provider. Embedded within the complaint is an issue of fairness. However counter-intuitive, the target for the complaint must be the Internet, itself. The root cause is a fundamental mismatch between application HTTP requests with TCP state, and the inadvertent conflict caused when one feedback control mechanisms sits atop another mechanism for the same purpose.

Stability, utilisation, and fairness, have long been cornerstones of network design. New distributed applications defy the network’s ability to preserve these tenets. New systems-level metrics and mechanisms are needed to reflect and characterise the quality of experience (QoE) of the application or user [1]. In addition, the increasingly widespread use of encryption, eg. HTTPS and HTTP/2, means that application participation is needed to ensure adequate service by any measure [2].

[1] A. Mansy, M. Fayed, and M Ammar. Network-Layer Fairness for Adaptive Video Streams. IFIP/IEEE Networking, 2015.

[2] J. Chen, M. Ammar, M. Fayed, R. Fonseca. “Client- driven QoE for SDN-controlled Streaming Video,” ACM SIGCOMM Quality of Experience Workshop, 2016.