[Asterisk-Users] T.38 fax summary

[Martijn van Oosterhout]

On Sun, Feb 27, 2005 at 05:32:49PM -0800, Lee Howard wrote:
> Quite right.  I'm sorry to have misled.
> 
> What happens is this (as an example scenario):
> 
> The receiver will, for an example, receive the post-page message.  The 
> sender expects a response to this.  The receiver, however, is required 
> to wait between 55 and 95 ms before transmitting the response.  The 
> sender will likely be looking for the post-page response immediately 
> after transmitting the post-page message.  Per spec the sender will 
> only wait about 3 seconds (per-spec between 2550 and 3450 ms) before 
> giving up wating and retransmitting the post-page message (and then 
> re-expecting the response).

Thank you. So the 1 second lag I suggested is too much, but the
principle is sound. Say we change it to half a second you're well under
the limit. The question then becomes, is a fixed half-a-second
jitterbuffer good enough to remove all the problematic jitter from the
signal. This is a testable assertion (though unfortunatly I don't have
the necessary equipment), simulating jitter is possible and hopefully
the jitterbuffer itself is tunable.

A tunable jitterbuffer sounds like a good idea, anyone actually thinking
of implementing it though?

Have a nice day,
-- 
Martijn van Oosterhout
Ecomtel Pty Ltd