Traffic Sampling methods for end-to-end QoS evaluation in large heterogeneous networks

Abstract: Research, education and business infrastructures based on large heterogeneous networks pose a new class of management problems such as on-line end-to-end performance monitoring over packet switched networks in support of multimedia services. A test and measurement system able to monitor the status of packet networks at end-to-end level and to evaluate the quality of service actually provided to the end users is presented in this paper. The basic idea behind the proposed solution is the introduction of sampling techniques in the measurement and estimation phases, in order to reduce the quantity of control data, of resources required to process it and hence to speed up all the further management functions. Sampling is introduced for relieving the complexity of these functions, which are usually carried out by means of heavy routines dealing with huge amount of data. The analysis is carried out by means of simulation on a very simple queueing model loaded by synthetic traffic and actual traces collected over an intercontinental ATM trunk. The rationale behind this choice is the search for a trade-off between the sampling rate and attained estimation accuracy, representing a theoretical and quantitative method usable by network operators to design new control tools. (C) 1998 Elsevier Science B.V. All rights reserved