A Distributed Caching Architecture for Over-the-Top Content Distribution

Over-the-Top (OTT) services encompass video and audio delivery over the Internet without the strict and direct control of Telecom operators, being attractive, low-cost and profitable. Due to the increasing use of the Internet and the increasing bandwidth provided by Telecom operators, excellent conditions were leveraged for the raise and growth of OTT multimedia streaming services, shown by the huge success of YouTube and Netflix. OTT services grow at a fast pace driven by a low barrier of entry, mostly because of little to no investment being required in infrastructures traditionally necessary to reach the masses. This fast-paced growth presents an opportunity for all the involved partners, but comes with several challenges, especially in terms of OTT content distribution scalability with high perceived QoE levels experienced by the consumers. This paper presents a novel Distributed Smart Management Cache (DSMC) architecture based on distributed caching model taking advantage of all horizontally available edge caches, thus avoiding repetition of content among caches of the same members group, which horizontally solves scalability challenges, enhancing clients' perceived Quality of Experience (QoE) in comparison to traditional decentralized architectures. Exhaustive tests were performed with several clients using a real QoE probe in different scenarios (fixed at home and mobile at street), with particular conditions imposed by consumer habits, and by network impairments (jitter, latency and poor bandwidth, etc.) from the involved technologies (Fiber, Wi-Fi and 4G LTE). The obtained results confirm that the proposed DSMC architecture plays an important role on providing QoE requirements and bandwidth consumption in the OTT delivery, reducing edge cache loads and consumed bandwidth by upstream content server/origin.