[Asterisk-Users] BAD/GOOD Echo Cancel

[Steve Underwood]

Ken D'Ambrosio wrote:

>For the record, I've done a couple of Asterisk installs, and HATED echo
>-- or feebly attempting to get Asterisk's flakey software algorithms to
>do anything about it.  Finally got sick 'n tired, and threw money at it
>-- got the Sangoma quad-span T1 card.
>
>And echo freaking VANISHED.  (Note that, with EC disabled, I do get echo
>about 1/6 of the places I call.  So it's really, truly working, and not
>just luck.)
>
>They use the G.168-2002 algorithm; I, personally, had never heard of it
>before, but I bounced it off a friend of mine (he's a hardware architect
>for a major VoIP switch manufacturer -- they sell to places like Time
>Warner), and he was of the opinion that G.168 is the _ONLY_ algorithm.
>
>So, from now on, I'm doing DSP-based EC.  And Sangoma just came out with
>some analog cards with EC -- haven't tried 'em out yet, but I'm looking
>forward to doing so.
>
>-Ken
>  
>
G.168-2002 is not an algorithm. It is a test spec. The algorithms are up 
to the implementor. They need to pass the tests in G.168-2002. Most only 
pass a subset of those tests. You need to look at the fine print to see 
what that subset it. If your friend thing G.168 is an algorithm, I would 
not trust his competance.

Steve