Analysis of average burst-assembly delay and applications in proportional service differentiation
In Optical Burst-Switched (OBS) networks, the limitation of optical buffering devices make it impractical to deploy conventional delay-based differentiation algorithms such as Active Queue Management, Weighted Fair Queuing, etc. Furthermore, only the delay that appears due to the burst-assembly process constitutes a variable quantity (all the other sources of delay are mostly fixed), it is then reasonable to make use of the burst-assembly algorithm to provide class-based delay differentiation. The aim of the following study is twofold: first it defines an average assembly delay metric, which represents the assembly delay experienced by a random arrival at the burst assembler of an edge OBS node; and second, this metric is used to define and configure a two-class burst-assembly policy, which gives preference to high-priority traffic over low-priority packet arrivals. The results show that, (1) tuning the parameters of the two-class assembly algorithm, the two classes of traffic exhibit different burst-assembly delay; and, (2) such parameters can be adjusted to provide a given differentiation ratio in the light of the proportional QoS differentiation approach proposed in the literature. A detailed analysis of the two-class assembly algorithm is given, along with an exhaustive set of experiments and numerical examples that validate the equations derived.
KeywordsOptical Burst Switching Size-based burst-assembly algorithm Average assembly delay Proportional delay-based service differentiation
Unable to display preview. Download preview PDF.
- 1.Turner J. (1999). Terabit burst switching. Journal of High Speed Networks 8: 3–16 Google Scholar
- 2.Qiao C., Yoo M. (1999). Optical Burst Switching (OBS) – A new paradigm for an optical Internet. Journal of High Speed Networks 8: 69–84 Google Scholar
- 6.Vokkarane, V., Haridoss, K., Jue, J.P.: Threshold-based burst assembly policies for QoS support in optical burst-switched networks. In Proceedings of SPIE/IEEE OPTICOMM (pp. 125–136). Massachusetts: Boston (2002)Google Scholar
- 8.Cao, X., Li, J., Chen, Y., Qiao, C.: Assembling TCP/IP packets in Optical Burst Switched networks. In Proceedings of IEEE GLOBECOM, (pp. 2808– 2812). Taipei: Taiwan (2002)Google Scholar
- 9.Yu, X., Chen, Y., Qiao, C.: Study of traffic statistics of assembled burst traffic in optical burst switched networks. In Proceedings of SPIE/IEEE OPTICOM, (pp. 149–159). Boston: Massachusetts (2002)Google Scholar
- 10.Hernández, J. A., Aracil, J., López, V., López de Vergara, J.: On the analysis of burst-assembly delay in OBS networks and applications in delay-based service differentiation. Photonic Network Communications (to appear) (2007)Google Scholar
- 22.Hernández, J. A., Aracil, J.: On the early release of Burst-Control Packets in Optical Burst Switched networks. In Proceedings of the international conference information networking, Estoril, Portugal (2007)Google Scholar
- 23.Karagiannis, T., Molle, M., Faloutsos, M., Broido, A.: A nonstationary Poisson view of Internet traffic. In IEEE INFOCOM, Vol. 3, (pp. 1558–1569). Honk Kong: PRC (2004)Google Scholar