Application Oriented Networking (AON): Adding Intelligence to Next-Generation Internet Routers

Abstract

Application Oriented Networking (AON) transforms the traditional network from pure packet-level routing to application-level processing by performing several customized computations at different nodes or routers. We study the operation of a Cisco AON system as a motivating example for our research.

A multimedia transcoding application, which dynamically transforms video streams to different output patterns to satisfy the bit rate and bandwidth requirements of a variety of clients, is considered in our research. We build an active router cluster for real MPEG stream transcoding service in our laboratory; and design, implement and evaluate various scheduling algorithms for the online transcoding operation. When transcoding operation is performed by multiple processors in the cluster, it produces out-of-order departure of media units and high jitter. We quantitatively define the QoS requirements for each media stream, and design a two-step QoS aware scheduling scheme, which is tested and compared with other algorithms.

Moving a packet from the network to the application level incurs large overhead due to PCI bottleneck and protocol stack in the operating system. Instead, we propose to move execution of the application to the network level by employing programmable network processors. We design and implement a web switch using Intel IXP 2400 network processor, and show its superiority compared to traditional Linux processing.