Accurate One-Way Delay Estimation: Limitations and Improvements
Accurate One-Way Delay Estimation: Limitations and Improvements
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DOI：
10.1109/tim.2012.2190551
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发表时间：
2012-04
影响因子：
5.6
通讯作者：
Ahmad Vakili;Jean-Charles Grégoire
中科院分区：
文献类型：
--
作者：
Ahmad Vakili;Jean-Charles Grégoire
单向时延（OWD）是交互式多媒体通信中评价终端用户感知质量的重要参数。在端点不协调且通常没有时钟同步的非对称网络中，精确的OWD测量是一个挑战。通常的方法估计连接的两个端点的OWD等于往返时间的一半，这在Internet中并不总是准确的。使用第三方节点增加独立方程的数量有助于最小二乘误差方法更准确地估计OWD。此外，向变量添加一些约束（例如，三个节点之间的owd）可以得到更精确的结果。本文研究了不同类型的约束对循环路径方法精度的影响，以提高OWD估计的精度。为了测量传输时延，提出了一种简单准确的测量方法。
The one-way delay (OWD) is a crucial parameter in interactive multimedia communications to assess the end users' perception of quality. Precise OWD measurement is a challenge in asymmetric networks in which endpoints are not coordinated and usually without clock synchronization. A usual method estimates the OWD for two endpoints of a connection as equal to one half of the round-trip time, which is not always accurate in the Internet. Employing a third-party node to increase the number of independent equations helps a least-square-error method to estimate the OWD more accurately. Furthermore, adding a couple of constraints to the variables (i.e., OWDs between three nodes) leads to even more precise results. This paper examines the effect of different types of constraints on the accuracy of the cyclic-path method to improve the OWD estimation. To measure the transmission delay, which has a crucial role in the OWD estimation improvement, a simple accurate method is introduced.