Quality of Service in VoIP Communication

Uhl, Tadeus

doi:10.1078/1434-8411-54100226

Cited by 11 publications

(6 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This characteristic property can be measured in several different ways. Tadeus Uhl [18] lists no fewer than four: the first is the MOS method (Mean Opinion Score) [12] based on the subjective judgement of a group of people. The perceived quality is graded on a scale from 1 to 5 (Table 2).…”

Section: Tests and Measurementsmentioning

confidence: 99%

Introducing wireless networking technologies as a teaching tool for foreign languages

Favier

Fynn

Misson

2007

Proceedings of the International Workshop on Educational Multimedia and Multimedia Education

View full text Add to dashboard Cite

This article presents a solution for a mobile console designed to enable teachers to move around their multimedia classroom away from the master console. This concept, intended more especially for language teaching laboratories, enables a permanent audio connection to be maintained between teacher and students. At the same time the teacher can move around the room to speak to any of the students whilst retaining supervision of the class.The focus of our study is on the use of voice over IP for communication in the laboratory between the teacher and the student workstations. Sound quality is indispensable in this type of teaching, which is why we have measured the quality of voice reproduction using standardized indicators.

show abstract

Section: Tests and Measurementsmentioning

confidence: 99%

Introducing wireless networking technologies as a teaching tool for foreign languages

Favier

Fynn

Misson

2007

Proceedings of the International Workshop on Educational Multimedia and Multimedia Education

View full text Add to dashboard Cite

show abstract

“…Indeed, four are the main performance indicators that characterize QoS for voice services over the Internet [3]- [4]: 1) average end-to-end delay, 2) delay variations (jitter), and 3) packet delivery ratio at the packetscale, and 4) new session blocking probability at the call-scale. In this respect, call admission control (CAC) mechanism is essential for QoS provisioning 1 in VoIP wireless networks.…”

Section: Introductionmentioning

confidence: 99%

Simplified joint call and packet level teletraffic analysis of CAC strategies for VoIP traffic in wireless networks

Castellanos-Lopez

Cruz-Perez

Rivero-Ángeles³

et al. 2012

2012 IEEE Wireless Communications and Networking Conference (WCNC)

View full text Add to dashboard Cite

In this paper, a simplified joint call and packet level teletraffic analysis method for performance evaluation of call admission control (CAC) strategies for voice over IP (VoIP) traffic over wireless access networks is proposed. The admission criterion of new sessions of the considered CAC strategies is based on either the total number of sessions or the number of active sessions. Arrivals and completions of VoIP sessions, on/off activity detection, and periodic and constant length packet generation of individual VoIP active sessions are modeled. Packet buffering, adaptive modulation coding, and proportional fair sharing scheduling are also considered. Our proposed analysis is based on the quantized queue and cross-level linked decomposition mechanisms that we introduce in this paper to drastically simplify the mathematical and computational procedures with no major impact on the accuracy of the results. The developed analysis allows evaluating the performance of the CAC strategies in terms of the most relevant QoS metrics of VoIP traffic at both call and packet level and, at the same time, mathematical and computational complexity are reduced with no major impact on the accuracy of numerical results.Keywords-Call admission control; VoIP; joint call and packet level analysis; time-scale decomposition; queue quantization; voice activity detection; session blocking; packet dropping probability.

show abstract

“…Transport of voice over an IPbased network demands a different set of QoS metrics than those required for the transport of data. Indeed, four are the main performance indicators that characterize QoS for voice services over the Internet [3]- [4]: 1) average end-to-end delay, 2) delay jitter, and 3) packet delivery ratio at the packet-scale, and 4) new session blocking probability at the call-scale. When new voice sessions are admitted into an already congested network, all calls in progress (not just the new calls) will experience increased packet loss and delay.…”

Section: Introductionmentioning

confidence: 99%

Joint Call and Packet Level Performance Analysis of CAC Strategies for VoIP Traffic in Wireless

Castellanos-Lopez

Rivero-Ángeles

Hernandez-Valdez³

et al. 2011

2011 IEEE Global Telecommunications Conference - GLOBECOM 2011

View full text Add to dashboard Cite

Call admission control (CAC) functionality is a critical requirement for guarantee the desired quality of service (QoS) for voice calls in IP-based wireless networks. In this paper, three different CAC strategies for voice over IP (VoIP) traffic over wireless access networks with packet buffering are mathematically analyzed through a joint call and packet level discrete time teletraffic model. The admission criterion (i.e., admission threshold) of new sessions of these strategies is based on either the total number of sessions, the number of active sessions (i.e., sessions in talk-spurt periods), or the number of packets queued in the buffer. Admission threshold and buffer size can be both controlled for QoS provisioning in terms of session blocking and packet dropping probabilities. Arrivals and completions of VoIP sessions, on/off activity detection, and periodic and constant length packet generation (of active sessions) of individual VoIP sessions are modeled. The developed teletraffic analysis allows to evaluate the performance of the CAC strategies in terms of the most relevant QoS metrics of VoIP traffic at both call and packet level (i.e., session blocking and packet dropping probabilities and packet delay). Finally, the maximum traffic attained by the different studied-CAC strategies (while QoS provisioning is guaranteed) is obtained.Keywords-Call admission control; VoIP; joint call and packet level analysis; QoS provisioning; voice activity detection; session blocking; packet dropping probability; packet delay.

show abstract

Quality of Service in VoIP Communication

Cited by 11 publications

References 0 publications

Introducing wireless networking technologies as a teaching tool for foreign languages

Introducing wireless networking technologies as a teaching tool for foreign languages

Simplified joint call and packet level teletraffic analysis of CAC strategies for VoIP traffic in wireless networks

Joint Call and Packet Level Performance Analysis of CAC Strategies for VoIP Traffic in Wireless

Contact Info

Product

Resources

About