Comparing the QoS of Internet audio mechanisms via formal methods
- 1 January 2001
- journal article
- Published by Association for Computing Machinery (ACM) in ACM Transactions on Modeling and Computer Simulation
- Vol. 11 (1), 1-42
- https://doi.org/10.1145/379525.379526
Abstract
We compute and compare the quality of service (QoS) of three soft real-time applications for audio transmissions over the Internet. The main metric we want to capture is the average packet audio playout delay vs. the packet loss rate as perceived by users. Other metrics we take into account are the packet loss rate vs. the receiving buffer capacity, the lateness of discarded packets vs. average packet audio playout delay, and the waiting time in the receiver buffer for the played packets vs. the average packet audio playout delay. The study is conducted in the algebraic language EMPA, by way of formal descriptions of the three audio mechanisms. The mechanisms are analyzed via simulation using the software tool TwoTowers under various (experimentally obtained or randomly generated) traffic conditions. The stochastic process algebra EMPA is used because it compositionally supports system modeling, it allows functional properties of systems to be formally verified (unlike conventional simulatiors), and it represents generally distributed durations (which come into play in the three audio mechanisms). The comparison reveals that in general no one of the three mechanisms outperforms the other two, as their performance depends on the traffic conditions.Keywords
This publication has 10 references indexed in Scilit:
- Design and Experimental Evaluation of an Adaptive Playout Delay Control Mechanism for Packetized Audio for Use over the InternetMultimedia Tools and Applications, 2001
- A Formal Approach to the Integration of Performance Aspects in the Modeling and Analysis of Concurrent SystemsInformation and Computation, 1998
- Successful multiparty audio communication over the InternetCommunications of the ACM, 1998
- Formal Performance Modelling and Evaluation of an Adaptive Mechanism for Packetised Audio over the InternetFormal Aspects of Computing, 1998
- Packet audio playout delay adjustment: performance bounds and algorithmsMultimedia Systems, 1998
- Twotowers: A Tool Integrating Functional and Performance Analysis of Concurrent SystemsIFIP Advances in Information and Communication Technology, 1998
- Real-time voice over packet-switched networksIEEE Network, 1998
- The NCSU Concurrency WorkbenchLecture Notes in Computer Science, 1996
- On the self-similar nature of Ethernet traffic (extended version)IEEE/ACM Transactions on Networking, 1994
- Automatic verification of finite-state concurrent systems using temporal logic specificationsACM Transactions on Programming Languages and Systems, 1986