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On Tuesday 25 November 2008 20:40:52 Dirk Heinrichs wrote: |
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> So yes, there is a difference. With htpdate, you synchronize against a |
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> _web_ server. How do you know it has a stable time source? OTOH, with ntp |
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> you synchronize against a specialized network _time_ server which is |
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> usually equiped with an accurate time souce*), using a protocol that was |
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> specifically desigend for that purpose (for example the time is adjusted |
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> without jumps), see http://www.ntp.org/ for all the details. |
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> *) As an example ptbtime1.ptb.de, hosted by the "Physikalisch-Technische |
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> Bundesanstalt" in germany is a so called stratum1 time server which is |
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> connected to the most accurate clock on earth, which provides the official |
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> time for germany. |
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An interesting sidenote on this. I work for a tier 1 carrier in my country and |
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right now we are replacing our ntp server. I don't work with this stuff every |
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day so I was most surprised to find that the new unit is actually a GPS |
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device and will no longer sync to the stratum 1 server run by our Scientific |
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Research Council. Apparently, this is good enough for ISP/internet purposes |
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for all practical intents and purposes. |
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-- |
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alan dot mckinnon at gmail dot com |
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