[Asterisk-Users] Codecs and bandwidth

[Tim Pushor]

Of course - ISDN is bi-directional. I guess saying that ULAW takes 130K+ 
bandwidth depending on the framing type (local lan, w/1 hop, vlan, etc) 
is not very clear. Thats total bandwidth. With lots of us at home and 
small business using asynchronous connections - we need to keep that in 
consideration.

Thanks for helping clear that up.

Tim


Steve Kennedy wrote:

>On Mon, Jul 18, 2005 at 11:28:57AM -0600, Tim Pushor wrote:
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>>>ulaw is 64Kb/s over a p2p link (or circuit switched in the PSTN world).
>>>If you then convert to IP there's at least a 20% overhead, can be more
>>>depending on the situation.
>>>Might take 100Kb/s
>>>      
>>>
>>Thats what I thought as well, so I was wondering why ISDN is 64K, but 
>>VOIP RTP/ulaw has been documented to be 64K per direction + packet 
>>overhead (132K+)
>>    
>>
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>ISDN is 64K per direction too, on a synchronous link i.e. 64K in both
>directions.
>
>I guess if you packetise etc then you've got to worry about both
>directions and the bandwidth to supoort it ...
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>Steve
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