[Freeswitch-users] send fax via google voice.

[Steve Underwood]

On 03/06/2011 01:18 PM, curriegrad2004 wrote:
> And relativity comes into play too.
Not unless you travel pretty fast. :-)
> Also you do need to realize that the packets sent via UDP isn't
> guaranteed to be in order as the fax machine expects the data to be
> sent in order, not out of order. That's the beauty of packet switched
> networks.
You will also see a small number of packets arrive twice for UDP over 
the internet, presumably due to router bugs.

Out of order packets are not, in themselves, a problem. A jitter buffer 
will reorder them, if they are not excessively delayed (and the jitter 
buffer is not of a broken design). The real issue is excessive jitter in 
the packet delivery times, which is functionally equivalent to packet 
loss - packets have to be dropped if they arrive too late for the real 
time deadline of the analogue channel.
> On Sat, Mar 5, 2011 at 7:29 PM, Steve Underwood<steveu at coppice.org>  wrote:
>> On 03/06/2011 11:21 AM, envelopes envelopes wrote:
>>> Why is PCMU codec not reliable?
>>>
>>>
>> Unsynchronised clocks, and packet loss.
>>
>> Steve
Steve