Resource-aware cloud-based elastic content delivery network with cost minimisation and QoS guarantee

Abstract

The distribution of digital multimedia, namely, audio, video, documents, images and Web pages is commonplace across today's Internet. The successful distribution of such multimedia, in particular video can be achieved using a number of proven architectures such as Internet Protocol Television (IPTV) and Over-The-Top (OTT)services. In order to maximise the scope and reach of this multimedia a need to combine aspects of the two architectures has arisen due to the rapid uptake of multimedia steaming to the plethora of Internet enabled devices that both architectures encompass. Content Delivery Networks (CDNs) have been proposed as an effective means to facilitate this unification in order to distribute multimedia in an efficient manner that enhances end-users' Web experience by replicating or copying content to edge of network locations in proximity to the end-user.

However, CDNs often face resource over-provisioning, performance degradation and Service Level Agreement (SLA) violations, thus incurring high operational costs, hardware under-utilisation and a limited scope and scale of their services. The emergence of Cloud computing as a commercial reality has created an opportunity whereby Internet Service Providers (ISPs) can leverage their Cloud resources to disseminate multimedia. However, Cloud resource provisioning techniques can still result in over-provisioning and under-utilisation. To move beyond these shortcomings this thesis sets out to establish the basis for developing advanced and efficient techniques to enable the utilisation of Cloud-based resources in a highly scalable, and cost-effective manner that reduces over-provisioning and under-utilisation while minimising latency and therefore maintaining the QoS/QoE expected by end-users for streaming multimedia.

In this context, this thesis addresses five key issues - when to replicate (request monitoring), where to replicate (resource monitoring), how to manage and enforce operational policies (request-redirection, cache management and load sharing), when to scale (trigger vertical scaling) and how to demonstrate a vertically scal-ing Cloud-based CDN applicability (measurement study and proof-of-concept implementation).

Date of Award	Jan 2014
Original language	English
Sponsors	British Telecom
Supervisor	Gerard Parr (Supervisor), Philip Morrow (Supervisor) & Bryan Scotney (Supervisor)