The Design Of A Distributed Network Measurement Platform Based On The Planetlab

With the rapid development of Internet, network and technology, Internettechnology and people’s daily life is becoming more and more closely. Whether in work,study or resting at home network technology can always provide people with a varietyof convenience. However, the rapid development of network technology has led to thenetwork performance can not meet the needs of network applications, Thus judgenetwork performance through network measurement technique becomes particularlyimportant. By measuring network implementation, we can research the network serviceperformance and analysis of network behavior. Finally, we can improve the quality ofnetwork services.During the measurement, to synchronize the time of different nodes has a greatinfluence on the results of measurement, especially in the large-scale networkmeasurement. We need to deploy tools in nodes with a large number and widelydistributed, The time difference between nodes has great influence on the accuracy ofthe results. In this work we discuss the network performance measurementtechnology,and developed a distributed network measurement platform based on thePlanetlab.The main work of this thesis is reflected in the following aspects:(1) This thesis propose a time synchronization stability comparison method basedon NTP after research the time synchronization technology. This method compares thetime synchronization between different nodes through NTP time synchronizationinformation captures. and select a relatively small time deviation node for networkperformance measurement.(2) In the one-way delay measurement, in order to eliminate measurement errorscaused by the frequency difference between nodes, this thesis propose a one-way delaycorrective algorithm based on forward and reverse delay measurement after researchexisting time corrective algorithm. Through the result of measurement of the forwardand reverse delay to calculate the frequency difference of time between themeasurement node.(3) After research the structure and characteristics of the Planetlab test bed, this thesis design a distributed network measurement platform based on the structure ofPlanetlab and DNMAI measurement platform. The thesis describes the structure of themeasuring system, deployment programs and the overall workflow in detail, as well asthree main tools for measuring system: transceiver package tools, console tools andserver.Finally, the measurement platform deployed in Planetlab and measure one-waydelay, bottleneck bandwidth and packet loss rate. The measurement select more stablenodes based on NTP stability comparison algorithm, and correct one-way delaymeasurement results through clock corrective algorithm mentioned above.Experiments show that the results of corrective measurement algorithm are moreaccurate.