[ntp:questions] ntpd transmit timestamp precision
Damion de Soto
damion at cyberguard.com.au
Mon Feb 13 06:08:59 UTC 2006
Hi,
I was wondering if anyone knew if ntpd contained code to do this (from RFC2030):
It is advisable to fill the non-significant low order bits of the
timestamp with a random, unbiased bitstring, both to avoid
systematic roundoff errors and as a means of loop detection and
replay detection (see below). One way of doing this is to generate
a random bitstring in a 64-bit word, then perform an arithmetic
right shift a number of bits equal to the number of significant
bits of the timestamp, then add the result to the original
timestamp.
The ntp packets from my platform all have the same fractional seconds, so I'm
guessing it does not. Is there any reason why not?
It seems a fairly trivial change in a couple of places in ntpd/ntp_proto.c
thanks in advance.
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| Damion de Soto --------------------------------------------------
| Software Engineer email: Damion_deSoto at au.securecomputing.com
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