A Methodology for Modeling, Performance Analysis, and Control of ATM Networks with Multi-Media Traffic

In this paper we review recent advances in developing a methodology for traffic modeling, performance evaluation, and control of ATM networks that can be used to support several aspects of Task 4.3 of the ATIRP project. Our methodology includes model matching and validation for multi-media traffic, analytical approximation techniques for time-efficient and accurate evaluation of end-to-end as well as intermediate node performance measures of multi-hop networks, and optimization of control (resource allocation) schemes

Performance of Bursty World Wide Web (WWW) Sources over ABR

We model World Wide Web (WWW) servers and clients running over an ATM network using the ABR (available bit rate) service. The WWW servers are modeled using a variant of the SPECweb96 benchmark, while the WWW clients are based on a model by Mah. The traffic generated by this application is typically bursty, i.e., it has active and idle periods in transmission. A timeout occurs after given amount of idle period. During idle period the underlying TCP congestion windows remain open until a timeout expires. These open windows may be used to send data in a burst when the application becomes active again. This raises the possibility of large switch queues if the source rates are not controlled by ABR. We study this problem and show that ABR scales well with a large number of bursty TCP sources in the system.Comment: Submitted to WebNet `97, Toronto, November 9