[Asterisk-Users] rfc3389 support in chan_sip?

[Joe Greco]

> Darren Sessions wrote:
> > Why not use an NTP timing source - go stratum 2 or 3. That should be 
> > plenty for a stable clock source.
> 
> *Timing* is what is needed, not _time_.  Two different things.  Besides 
> the obvious problems with using a remote network resource as a timing 
> device, I don't think many NTP server admins would enjoy you requesting 
> a _time_ update on the order of 1000+ times a second?  RTP not relying 
> on incoming RTP stream is going to require ?hardware? on the machine. 
> My $0.02.

There aren't many problems having a remote network resource as a time
service source.  NTP was designed precisely to solve that problem.

Getting your local clock sync'ed up to that is a problem that is already
solved.  You need not ask a remote server a thousand times a second for
the time:  you can ask your *local* *machine* which is synchronized via
NTP.  All the hard work of making sure that the local clock is running
accurately and smoothly is already done for you when you sync your clock
via NTP to known good sources.

Now, whether or not there's a convenient *way* to use the local machine
as a timing source is another matter.  I don't really know what's needed
for Asterisk's 3389 implementation.  People frequently want to do something
like select or read against a file descriptor in order to receive a
wakeup from the OS.  This would be purely a kernel software issue in the
case of using the system itself as a timing source.

... JG
-- 
Joe Greco - sol.net Network Services - Milwaukee, WI - http://www.sol.net
"We call it the 'one bite at the apple' rule. Give me one chance [and] then I
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