The NIProxy: a Flexible Proxy Server Supporting Client Bandwidth Management and Multimedia Service Provision

We present the NIProxy, a flexible network intermediary which aims to improve the Quality of Experience (QoE) of users of networked applications by pushing more intelligence into the network. More specifically, the NIProxy is network- as well as application-aware, meaning it has knowledge of both the transportation network and the application(s) it is serving. This dual awareness is exploited to improve user QoE in two complementary ways. First of all, the NIProxy is capable of dynamically distributing a client´s available downstream bandwidth over the different network streams generated by a networked application. Secondly, the NIProxy supports multimedia service provision, meaning it can apply services on multimedia streams on behalf of its clients. An important feature of the NIProxy is that its two QoE-improving mechanisms are not isolated entities but instead can interact with each other. A comprehensive discussion of the NIProxy´s software architecture is provided and the implementation of an example service, which adds video transcoding functionality to the NIProxy, is described Finally, presented experimental results clearly demonstrate the effectiveness of our approach.