RE: [802.3af] clocking over Ethernet
> I would also lke a method of achieving synchronisation to a few
> microseconds via Ethernet.
Achieving that level of sync over a large network is
difficult at best.
I work for Peak Audio (part of Cirrus Logic), and we've
been using Ethernet for distribution of digital audio
over an Ethernet based network. The difference between
us and "the other guy" is that we're doing 64+ channels
of uncompressed real-time audio. This requires
synchronizing the audio sample clocks across the entire
network. Our spec says that we can get 1/4 sample clock
accuracy at 48 KHz over a 2 km wide Ethernet network.
We're actually getting better than that (1/10th sample,
I think).
Here's a link to some CobraNet (that's what we call it)
stuff. It's somewhat audio-biased rather than timing
biased, and not very technical, but it might be at least
a little informative.
http://www.peakaudio.com/CobraNet/index.htm
That being said, I think we're getting off topic here.
If anyone has questions about this feel free to email
me directly.
David Kessner
davidk@xxxxxxxxxxxxx