Title: Atm Switch Performance Testing Experiences Distribution: Atm Forum Technical Working Group Members (af-test, Af-tm) 1. Computing Mimo Frame Latency from Ctd: 2. Mimo Latency Measurement Tests without Background Traffic 2.1. Configuration

We experimented with the latency, throughput, fairness, and frame loss rate metrics. The results of these measurements are helpful in refining the baseline text. ************************************************************************ Source: Gojko Babic, Arjan Durresi, Raj Jain The Ohio State University Department of CIS Columbus, OH 43210-1277 Contact Phone: 614-292-3989, Fax: 614-292-2911, Email: [email protected] The presentation of this contribution at the ATM Forum is sponsored by NASA. ************************************************************************ Date: February 1997 ************************************************************************ Distribution: ATM Forum Technical Working Group Members (AF-TEST, AF-TM) ************************************************************************ Notice: This contribution has been prepared to assist the ATM Forum. It is offered to the Forum as a basis for discussion and is not a binding proposal on the part of any of the contributing organizations. The statements are subject to change in form and content after further study. Specifically, the contributors reserve the right to add to, amend or modify the statements contained herein. ************************************************************************ We measured throughput and frame latency of a commercial switch using a commercial monitor. The purpose of this contribution is to highlight our experiences in the following areas: 1. Frame Statistics from Cell Statistics: Current monitors do not measure any frame level statistics. Therefore, it is necessary to derive frame level statistics based on cell statistics. 2. Monitor Overhead: Monitors have finite accuracy. It is necessary to take this into account when computing the frame level performance. 3. Background Traffic: The baseline document does not yet contain information on background traffic. The tests presented here will help make progress in that direction. 4. Cell Transfer Delay: Cell level latency has a high variance and, therefore, the average cell transfer latency is statistically not very meaningful. 5. Lossless, Peak, and Full-Load Throughput: The baseline defines three types of throughputs. However, we found that lossless throughput is the only one that is meaningful. Others can be inferred.