Linda Cline

DirectShow/sup TM/ RTP support for adaptivity in networked multimedia applications

Execution of a collaboration application or a distributed game involves many individual multimedia applications that concurrently generate and consume audio and video streams. As the resource requirements of individual streams change and as streams/applications are started or terminated, the amount of available resources may change dynamically. Networked MultiMedia applications must be willing to adapt to these changes by taking advantage of the fact that they can deliver varying levels of service that are acceptable to users. The paper addresses the problem of adding network and host adaptive capability to DirectShow/sup TM/ RTP. DirectShow/sup TM/ is Microsofts architecture for capture and presentation of multimedia data. DirectShow RTP is a framework that extends the DirectShow architecture, adding support for streaming multimedia data using the RTP protocol. We have extended this framework by adding support for streaming applications which dynamically compensate for varying resource availability on the local host and on the computer networks being used to deliver multimedia data to and from these applications. The lessons learned are useful both to applications and to designers of frameworks used to build such applications.

Enabling Architectures for Next Generation Optical Networks

As the demand grows for higher network access speeds, technologies such as optical fiber have begun to overtake traditional copper wire for data transport in short haul networks as well as long haul networks. Optical networking plays a growing role in next generation networks with new capabilities such as LCAS (Link Capacity Adjustment Scheme) and Virtual Concatenation (VC), and services such as dynamic provisioning and traffic grooming. While these emerging capabilities hold the promise of an intelligent optical network, there are still obstacles. Protocols and standards to support these capabilities are still evolving. In addition, in order to realize the new benefits, carriers and providers must invest in new optical equipment, as well as upgrades to existing equipment. In the current economic environment, a choice which leverages lower cost equipment with software which can provide advanced functionality is significantly more attractive than expensive alternatives. In addition, upgradeable software-based components provide future cost savings as well as flexibility in supporting new and changing protocols and standards. In this paper, we discuss each of these issues in detail and present a solution for optical services and applications, including Optical Burst Switching, using a network processor based platform to overcome the obstacles facing next generation optical networks.