A System Theoretic Approach to Bandwidth Estimation
Abstract
It is shown that bandwidth estimation in packet networks can be viewed in terms of min-plus linear system theory. The available bandwidth of a link or complete path is expressed in terms of a {\em service curve}, which is a function that appears in the network calculus to express the service available to a traffic flow. The service curve is estimated based on measurements of a sequence of probing packets or passive measurements of a sample path of arrivals. It is shown that existing bandwidth estimation methods can be derived in the min-plus algebra of the network calculus, thus providing further mathematical justification for these methods. Principal difficulties of estimating available bandwidth from measurement of network probes are related to potential non-linearities of the underlying network. When networks are viewed as systems that operate either in a linear or in a non-linear regime, it is argued that probing schemes extract the most information at a point when the network crosses from a linear to a non-linear regime. Experiments on the Emulab testbed at the University of Utah evaluate the robustness of the system theoretic interpretation of networks in practice. Multi-node experiments evaluate how well the convolution operation of the min-plus algebra provides estimates for the available bandwidth of a path from estimates of individual links.
- Publication:
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arXiv e-prints
- Pub Date:
- January 2008
- DOI:
- 10.48550/arXiv.0801.0455
- arXiv:
- arXiv:0801.0455
- Bibcode:
- 2008arXiv0801.0455L
- Keywords:
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- Computer Science - Networking and Internet Architecture;
- Computer Science - Performance;
- C.4
- E-Print:
- 23 pages