An Experimental Evaluation of Voice-over-IP Quality over the Datagram Congestion Control Protocol
نویسندگان
چکیده
The presence of voice-over-IP traffic in the Internet is constantly increasing, as it offers improved connectivity and quality-of-service comparable to classical telephony at costs that the rival circuit-switched telephony systems cannot match. This paper evaluates the audio quality of voice-overIP calls that use the Datagram Congestion Control Protocol (DCCP), a congestion-controlled alternative for the User Datagram Protocol (UDP) that carries most voice-over-IP calls today. A framework for assessing the impact of the transport layer on VoIP streams is presented. The experimental results illustrate some of the problems that the proposed congestion control methods face in preserving the perceived quality of VoIP transmission.
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