[asterisk-users] Linksys SPA-3102

[Rich Adamson]

Inline...

Barry D. Hassler wrote:
> On Sat, 2006-08-19 at 00:12 -0500, Rich Adamson wrote:
>> Barry D. Hassler wrote:
>> > Any further experience with the 3102? I'm looking for a solution to 
>> > connect 2 CO lines and a set of 2-line phones to my asterisk server 
>> > (along with a bunch of SIP phones). Would 2 of these work well for that?
>> > 
>> > Hopefully no echo problems! That would kill this project? I'm still 
>> > searching for one peice of hardware that would have 2 FXO and 2 FXO 
>> > ports on it, but haven't stumbled on it yet....
>>
>> The only way to know for sure whether the spa will provide reasonable 
>> service is to try it on the actual pstn line to be used. There is no 
>> other way for anyone to tell you anything different. The quality of the 
>> audio & echo is 100% dependent on the exact pstn line characteristics, etc.
>>
>> Two other reasonable alternatives are:
>> Digium TDM card with two fxo and two fxs modules.
>> Sangoma A200d card with one fxo module (has two lines on it) and one fxs 
>> module (has two lines on it).
> Yes, this would definitely work. J'm trying to avoid running phone lines 
> the distance between the existing demarc and the asterisk server :-)
> But, it would probably be the best solution.
> 
> Actually, as I look further, I don't think the 3102 will work in this 
> environment at all for what I want. (incoming FXO calls go to Asterisk 
> server, and through its dial plan, which might include ringing the 
> analog phones on the FXS ports).

That has worked just fine, even with the old spa3000. But, echo and dtmf 
talk-off could be an issue.

> I did find AudioCodes MediaPack MP-114, which has exactly the 
> configuration I want (2 FXO, 2 FXS), but have to be registered to get 
> any documentation on the units.

Don't know anything about the MP-114 at all. If that were a solid box, 
I'd have to guess you'd see lots of folks recommending them. That's not 
the case over the last three years, so would have to guess they might 
have the same echo issues as the spa3k. (translated: poor to acceptable 
echo cancellation likely due to under-horsepowered box with software EC.

> 2 Grandstream HT-488's looks like a possibility too....

The HT-488's are total crap. The only reason that box has an fxo port is 
for failures, cutting the fxs directly to the fxo. Also poor echo 
cancellation.

> I think I'll just run the phone lines into the server, and add more 
> cards there.... :-)

Better choice. However, extending the fxs function to distant locations 
with an sip adapter certainly is feasible.

The problem with almost all of the small/inexpensive sip adapters that 
have fxo ports is their software echo cancelers have rather narrow 
operating limits. Any calls that exceed the limits will incur echo, and 
that can vary from one call to another.