[Asterisk-Users] Re: Why Asterisk can't cope with silence suppression?

[Chris Wade]

Keith O'Brien wrote:
>  
> 
>> >>Essentially its because * has been architected to send an rtp packet 
> "after" receiving a packet. If * never "see's" and >>>incoming rtp 
> packet, then it won't send an rtp packet (which usually contains some 
> amount of audio). Thus choppy audio >>>in one direction.
> 
> So why can’t * just play comfort noise when it doesn’t see any rtp 
> packets in a particular bearer channel?   Unless I am missing something 
> fundamental this doesn’t seem to be a huge architectural change.  I’d 
> have to agree that a lack of proper vad support is a major shortcoming.

It's more than that, from what I know a *missing* RTP packet could be 
'silence' (vad) or it could be 'network related' (jitter).  * not seeing 
a packet doesn't always mean it was vad, it might mean your network had 
a split second (subsecond) hiccup that caused the packet to disappear - 
both 'look the same' to *.  This is why someone had already mentioned 
the idea that the new jitter-buffer might handle this better/correctly.

-Chris

PS: I may be completely wrong - a guru's statement (although already 
listed in the archives multiple times) would be appreciated.