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Optimization and phase transitions in a chaotic model of data traffic
M Woolf1, D K Arrowsmith, R J Mondragón-C
1Mathematics Research Centre, Queen Mary, University of London, London E1 4NS, United Kingdom.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|November 22, 2002
Summary
This study shows that using long-range dependence (LRD) sources in packet-switching networks, instead of Poisson-like ones, significantly enhances network-induced LRD. This leads to a more dramatic congestion phase transition and throughput collapse.
Area of Science:
- Computer Science
- Network Engineering
- Applied Mathematics
Background:
- Previous models of packet-switching networks used Poisson-like traffic sources.
- Long-range dependence (LRD) in autocorrelation behavior was observed in queue length dynamics.
- Actual network traffic exhibits long-range autocorrelation.
Purpose of the Study:
- To investigate the effect of introducing LRD behavior at an earlier stage in packet-switching network models.
- To simulate network traffic more realistically by replacing Poisson-like sources with LRD sources.
- To analyze the impact of LRD sources on network congestion and performance.
Main Methods:
- Replaced Poisson-like traffic sources with LRD sources modeled using chaotic maps.
- Conducted extensive numerical simulations comparing Poisson and LRD sources.
- Adapted the model to include congestion control mechanisms.
Main Results:
- Demonstrated natural network-induced LRD even with purely Poisson sources.
- Showed a strong enhancement of LRD when LRD sources were introduced.
- Observed a phase transition to a congested state with increased traffic load, leading to dramatic increases in packet delivery time and throughput collapse.
- Analyzed the impact of congestion control mechanisms.
Conclusions:
- Introducing LRD sources amplifies network-induced LRD and exacerbates congestion.
- The findings highlight the importance of considering LRD in network traffic modeling for accurate performance prediction.
- Congestion control mechanisms play a crucial role in mitigating the effects of LRD and congestion.
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