DiffServ experiments: evaluation of some approaches to quality of service control over the Alcatel-NCSU Internet2 testbed
Aziz Mohammed, Mladen Alan Vouk, Emanuele Jones, Zyad Dwekat · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2002
Technological communities that are formed on the basis university, industry and government partnerships are developing and deploying advanced network applications and technologies, accelerating the creation of tomorrow's Internet. Alcatel and North Carolina State University (NCSU) have jointly launched a virtual Lab between Alcatel's Research & Innovation Center in Plano, TX and NCSU campus at Raleigh, NC across the Internet2 national backbone network. The objective of this co-operative work is to conduct a large-scale field trial in the currently deployed state of the art QoS technologies and investigate areas of improvement. Results from phase one of our work in a Differentiated services (DiffServ) experiments over this testbed involving network equipment from Alcatel and other third party vendors show that DiffServ is capable of delivering the premium service using its expedited forwarding (EF) per-hop behaviour (PHB) for a large class of bandwidth starving applications. However, it is found that DiffServ needs some additional mechanisms to efficiently deliver similar services for jitters and delay sensitive applications, especially in a condition of severely congested network. The situation is even more complicated when one considers resource-sharing environments beyond the extreme cases of EF and best effort (BE) only. The second phase of our work involves investigating empirically and through simulation, a fine-grained new integrated scheduling scheme to extend the DiffServ with a variety of adaptive queue management (AQM) solutions and study their effect on end-to-end (e2e) DiffServ experiments involving not only EF/BE but also assured forwarding (AF) traffic.