A Survey of the NTP Network
نویسنده
چکیده
The Network Time Protocol creates a network of hosts on the Internet that synchronize time. This paper describes the methods and results of a survey of the NTP network conducted by a “spider” that queried all findable NTP hosts on the Internet. This survey estimates the NTP network contains at least 175,000 hosts. An analysis of the survey data collects network size, timing, and topology information and compares them to results from previous surveys over ten years. An analysis of the stratum 1 clocks shows a surprising number of bad timekeepers. Data and software from this survey is online at http: //www.media.mit.edu/ nelson/research/ntp-survey99/
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