[ntp:questions] Reg: NTP accuracy

Jan Ceuleers janspam.ceuleers at skynet.be
Mon Dec 3 19:32:36 UTC 2007


linux newbie wrote:
> HI,
> Need following clarification.
> 
> Our Application needs to have two individual hardware (with DSP processor)
> to have same crystal clock freqency. Though individual boards are alike, due
> to environmental factors there might be drift after long run.

This suggests that you need frequency synchronisation, not time-of-day 
synchronisation. Frequency synchronisation is used a lot in 
telecommunications networks (e.g. SDH/SONET).

> As the two boards are connected to local LAN through ethernet, we feel by
> comparing time at regular intervals can determine any drift in clock.
> (assuming one board as server and another as client).

As telecommunications networks evolve from TDM to packet, there is also 
an increased need to transport synchronisation information across packet 
networks.

Work is ongoing in the IETF (e.g. TICTOC) and elsewhere (e.g. IEEE 
1588). But before choosing a solution, you need to be clear on what 
problem you are trying to solve.

Cheers, Jan




More information about the questions mailing list