Dynamic Search Algorithm, Dsa+

Abstract

Network managers seek to provide QoS to users through the proper allocation of resources. The allocation should be as efficient as possible, which signifies reduced resource amounts as well as few renegotiations. Reducing the allocation amount provides higher utilization of resources, while reducing the number of renegotiations lessens the signaling strain on the network. Users are also interested in efficient allocations, since resources are expected to have costs associated with them (volume and renegotiation). In the previous chapter a review of different bandwidth allocation techniques was provided. Of the different approaches presented, on-line methods are the most versatile. On-line methods have the ability to determine the appropriate bandwidth amounts with limited a priori information; therefore, these methods are appropriate for stored or live media. Yet, few on-line methods attempt to reduce the allocation amount as well as the number of renegotiations. In this chapter a single-user, on-line allocation method called the Dynamic Search Algorithm (DSA+) is presented [40]. DSA+ allocates resources to meet a desired QoS. In this thesis, DSA+ is used to allocate link bandwidth in order to provide a desired Cell Loss Probability (CLP). DSA+ has the advantages of other on-line allocation methods; however, it is unique because it attempts to reduce the number of renegotiations and can manage link bandwidth for VBR sources. In the experimental section, DSA+ is used to control the loss rate of simulated traffic and actual MPEG-compressed videos by the appropriate allocation of link bandwidth. Other on-line and off-line algorithms were also implemented