Delay-throughput curves for timer-based OBS burstifiers with light load

• Published in: Journal of lightwave technology Vol. 24; no. 1; pp. 277 - 285
• Main Authors: Izal, M., Aracil, J., Morato, D., Magana, E.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.01.2006; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Adaptive algorithms; Algorithms; Applied sciences; Assembly; Burstification algorithms; Bursting; Delay; Delay effects; Exact sciences and technology; Flattening; Optical burst switching; Optical fiber communications; Optical network units; Optical packet switching; Optical receivers; Optical switches; Optical telecommunications; Optimization; performance evaluation of OBS networks; Studies; Switching; Switching and signalling; Switching circuits; Systems, networks and services of telecommunications; Telecommunication traffic; Telecommunications; Telecommunications and information theory; Teletraffic; Throughput; Transmission and modulation (techniques and equipments); Unity; Performance evaluation; Packet switched network; Packet switching; Adaptive algorithm; Information rate; Teletraffic; Information transmission; Burstification algorithms; Optical fiber network; Accuracy; Simulation; Optical switching; Telecommunication network; performance evaluation of OBS networks; Optical fiber communication; Delay time
• ISSN: 0733-8724; 1558-2213
• DOI: 10.1109/JLT.2005.860140

The optical burst switching (OBS) burstifier delay-throughput curves are analyzed in this paper. The burstifier incorporates a timer-based scheme with minimum burst size, i.e., bursts are subject to padding in light-load scenarios. Precisely, due to this padding effect, the burstifier normalized throughput may not be equal to unity. Conversely, in a high-load scenario, padding will seldom occur. For the interesting light-load scenario, the throughput-delay curves are derived and the obtained results are assessed against those obtained by trace-driven simulation. The influence of long-range dependence and instantaneous variability is analyzed to conclude that there is a threshold timeout value that makes the throughput curves flatten out to unity. This result motivates the introduction of adaptive burstification algorithms, which provide a timeout value that minimizes delay, yet keeps the throughput very close to unity. The dependence of such optimum timeout value with traffic long-range dependence and instantaneous burstiness is discussed. Finally, three different adaptive timeout algorithms are proposed, which trade off complexity versus accuracy.