Network Measurement Based On NTP And HTTP

With the rapid development of computer network, the network measurement technology becomes more and more important. Network measurement is not only helpful to have an acquaintance with the running of network, but also helpful to provide the necessary precondition for description and control of network behaviors. Two aspects of work are finished based on NTP and HTTP.Firstly, as the source of synchronization time, the accuracy of NTP servers directly affects the precision and stabilization of clock synchronization. Based on analysis of NTP in detail, the NTP servers measurement software is developed, and applied to the measurement of NTP servers in CERNET. By analysis and statistics of data gained, The precision distribution chart of NTP servers in CERNET is drawn and very good result of analysis is provided for constructing accurate and secure time synchronization service in CERNET.Secondly, Speed and stability of websites are the important factors of websites quality and keys of use of Internet. With the websites RTT measurement software by self developed, the RTT of websites are measured. By analysis and statistics of data gained, the curves of RTT-Time are drawn to show the speed and stability of websites, the network stability index is defined to describe network stability quantitatively, and the algorithm of network stability index is given as well.