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5. Time Synchronization

I keep my computers' clocks set typically to within a few hundredths of a second of "true time" using the NTP network time protocol software package. A faster connection than 28.8K would result in somewhat better synchronization, but it's certainly providing service that's as good as I need.

ISP's ought to set up as "Stratum 2" time servers so they can provide time setting services to their customers, and PCs should correspondingly reset their clocks on a regular basis via NTP. This would be helpful as at least a partial resolution to some of the errors that result from buggy news posting software particularly on Microsoft platforms.

Correct times are useful on a LAN for managing changes to files, and are critical for managing concurrent transactions in distributed client/server systems. At work, it's often not worth using any time-based applications like PIMs if users are not consistently synchronizing their clocks to the same time.

At present, there are a few publicly-accessible Stratum 1 servers and many readily accessible Stratum 2 servers. With more usage of NTP:

The protocol recognizes 16 strata, which is enough to handle synchronization requirements even within the scope of unimaginable levels of expansion on and around Planet Earth. A new scheme would doubtless be required if there were significant off-Earth activities, as other bodies in our solar system have (amongst other differences) days of different lengths, and are significant distances away in terms of the time it takes for electromagnetic radiation to go back and forth.

The above represents the " theory" of how things ought to be done if people acted intelligently in good faith. Reality has turned out somewhat differently. People writing Windows clients or selling hardware routers have hardcoded server names into them that are often overpowering Stratum 1 servers. See NTP pool for a solution that is in progress to allow public use. Many operators of Stratum 1 servers are now requiring private crypto keys in order to connect, and those that do not have those keys may receive a " kiss of death" packet, which provides consciously inaccurate time information, stratum set to 0, along with a message indicating the nature of the rejection of service.

5.1. Hardware and Software Vendors

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Contact me at cbbrowne@acm.org