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Full-Text Articles in Systems and Communications
State Acquisition In Computer Networks, Ruairí De Fréin
State Acquisition In Computer Networks, Ruairí De Fréin
Conference papers
We establish that State Acquisition should be per- formed in networks at a rate which is consistent with the rate-of-change of the element or service being observed. We demonstrate that many existing monitoring and service-level prediction tools do not acquire network state in an appropriate manner. To address this challenge: (1) we define the rate-of- change of different applications; (2) we use methods for analysis of unevenly spaced time series, specifically, time series arising from video and voice applications, to estimate the rate-of-change of these services; and finally, (3) we demonstrate how to acquire network state accurately for a number …
Assessing The Quality Of Voip Transmission Affected By Playout Buffer Scheme, Miroslaw Narbutt, Mark Davis
Assessing The Quality Of Voip Transmission Affected By Playout Buffer Scheme, Miroslaw Narbutt, Mark Davis
Conference papers
Delay, echo, encoding scheme, and packet loss all influence perceived quality of conversational speech transmitted over packet networks. Therefore, the choice of a buffer algorithm cannot be solely based on statistical loss/delay trade-off metrics. Also subjective “listening tests” or the newer ITU-T PESQ method, which don’t consider the effect of mouth-to-ear delay are inappropriate. We proposed a method for assessing VoIP call quality by extending the ITU-T E-model concept. This method provides a direct link to perceived conversational speech quality by estimating user satisfaction from the combined effect of information loss, delay and echo.