Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!ucsd!ucbvax!CS.UCLA.EDU!wales From: wales@CS.UCLA.EDU (Rich Wales) Newsgroups: comp.protocols.time.ntp Subject: Re: What is protocols.time.ntp? Message-ID: <900718.192332z.16373.wales@valeria.cs.ucla.edu> Date: 18 Jul 90 19:23:32 GMT References: <19089@well.sf.ca.us> Sender: daemon@ucbvax.BERKELEY.EDU Distribution: inet Organization: The Internet Lines: 29 Bob -- Replying to your question about what NTP is: NTP (Network Time Protocol) is a network clock synchronization protocol -- similar in some ways to, but more advanced than, TSP and TIMED. NTP uses UDP (User Datagram Protocol -- a connectionless datagram service which is part of the TCP/IP protocol suite) to exchange time-stamped infor- mation packets between hosts. An "NTP daemon" runs on each host, sends periodic queries to other hosts, and uses a complex filtering algorithm to evaluate the incoming information and keep the local clock running accurately and smoothly over time. Numerous hosts on the Internet are using radio clocks which listen to author- itative time sources such as the US NIST (formerly NBS) radio station WWVB. These hosts function as "stratum-1" NTP servers to distribute time stamps to other hosts. A local organization can set up one or more "stratum-2" NTP servers, which synchronize off a set of stratum-1 servers and in turn provide time information for the rest of the organization. NTP has been designed for high efficiency, stability, and robustness. These considerations -- together with the fact that so many radio-clock hosts offer high-accuracy time service on the Internet via NTP -- make the protocol an attractive and inexpensive way of keeping your system clocks in sync. -- Rich Wales // UCLA Computer Science Department 3531 Boelter Hall // Los Angeles, CA 90024-1596 // +1 (213) 825-5683 "Indeed! Twenty-four is the gateway to heroic salvation."