[ntp:questions] Re: SNTP Server Question

Richard B. Gilbert rgilbert88 at comcast.net
Thu Jun 30 18:29:02 UTC 2005

jassy2005 at gmail.com wrote:

>Thanks Harlan!!
>Yeah, I read the RFC and it clearly states that but unfortunately my
>device - which would in future would be configurable to be used  as
>either SNTP server or SNTP client does have 10/100TX interface but
>lacks any modem support.
>So if I decide to use my own local clock as reference then is it
>possible can I just copy the code from NTP distribution for local clock
>reference and use  for my own purpose in SNTP.
>Please suggest - because SNTP is just a subset of NTP!!
>>From I can get NTP source code??
>Harlan Stenn wrote:
>>In reality you can do whatever you want.
>>Please see "6. SNTP Server Operations" about half-way in to
>> http://www.ietf.org/internet-drafts/draft-mills-sntp-v4-00.txt
>>where it says: "a[n] SNTP server should be operated only in conjunction with
>>a source of external synchronization, such as a reliable radio clock or
>>telephone modem.".
Use the local clock if, and only if:
a. you have no choice, and
b. you don't really care about the correct time

The local clock on just about any kind of computer I can think of keeps 
time less well than the typical cheap wrist watch.   The wrist watch, 
after all, has no other purpose and, if it does not meet certain minimum 
standards of accuracy, will not get very far in the market place!  The 
computer, OTOH, has a clock merely as an afterthought!   The original 
IBM PC and the PC/XT had no clock; if you wanted one you purchased a 
third party "multifunction card" and installed it.

Your local clock could gain or lose as much as twenty minutes a month!

Most people here tend to feel that NO system or device whatever should 
be serving time unless its time source is traceable to a national standard!

No one can stop you from doing so but you will not find many people to 
aid and abet you!

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