Evaluation of Packet Transmission Delay Variation in the G/G/1 System

摘要

Analyzing the performance parameters of IP-networks when processing multimedia streams is a very important task. There are many approaches to evaluating the quality of service parameters in the G/G/1 system. Changing the packet delay in the network is a very significant parameter that determines the quality of traffic processing. It is particularly important for multimedia streams. The delay variation is generally defined as a packet jitter. However, the analysis of the delay variation is often based on assumptions that do not allow the parameters to be determined with the required accuracy. This paper presents a new approach to defining packet delay variation in the G/G/1 system as delay variation. The presented approach is based on approximation of arbitrary distributions by hyperexponential distributions, i.e. modeling the G/G/1 system by the H_2/H_2/1 system. The EM algorithm is used to estimate the parameters of hyperexponential distributions. The paper presents the results of simulation. The packet delay variation was evaluated when processing traffic registered on a real network, CBR traffic, traffic with Pareto distribution of time intervals between packets and packet lengths, and traffic with exponential distribution of time intervals between incoming packets. Due to the fact that CBR traffic has explicit correlated properties, it can be noted that the presence of correlation inherent in CBR traffic leads to a decrease in delay variation.