[asterisk-users] Benefit of PRI vs SIP trunk calls

[Jim Dickenson]

Does Asterisk, currently using version 1.4, get any more information about the result of an outbound call made over a PRI line compared to a call via a SIP trunk?

As an example, in a PRI call there is this message that shows up on the console:

[2011-01-05 14:59:02]     -- Channel 23 detected a CED tone from the network.

for a call to a fax machine. Does asterisk set anything that a dialplan can access that can know the call was to a fax machine?

If a call is placed to a number that is disconnected so a special information tone is played can either a PRI call or a SIP call know this without analyzing the audio stream?

Are there reasons to prefer the use of PRI over SIP or SIP over PRI?

I would like people's opinions as to if one form is better than the other in any meaningful way.

Thanks for you feed-back.
-- 
Jim Dickenson
mailto:dickenson at cfmc.com

CfMC
http://www.cfmc.com/