I would sum it up this way; never _EVER_ do an Asterisk install at a client site without hardware echo cancel. End of story.
Even when the software echo cancel in Asterisk is working at its best, it does not come close to meeting the ITU g168 standard. Put another way, if you don't use a hardware echo canceler with Asterisk, I guarantee you will get the comment "I'm getting echo on some calls." By the way, I should qualify the above statement by saying there now is a high performance software echo canceler available for asterisk which is g168 compliant. In fact, my understanding is it is the same code used inside the hardware echo canceler and so it should produce the same result assuming you have enough CPU. http://www.digium.com/en/products/software/hpec.php But note; it is not available for the T1 cards for the simple reason that it is so CPU intensive that the maximum number of channels current CPUs can support is about 8. John On Wed, 2007-08-08 at 15:08 -0400, Henry L.Coleman wrote: > Hi all, I have a client who is getting a T1 from Bell. As I don't have any > experience in the quality of various vendors PCI cards and if echo > cancellation is really required I am looking for some real life experience > on these products. I have heard good things about Sangoma so I will > probably go with them, but the echo card is twice the price of the > standard T1 card and as the client is not flush with money I would prefer > to use the least expensive option. I understand that the echo cancellation > is under software control but how much overhead does this really add to > the system ? If anyone out there is using the A101 card I would grateful > if they could let me know if there are any quality issues with this card. > --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
