[asterisk-users] USB dahdi fxo ?

[Greg Troxel]

sean darcy <seandarcy2 at gmail.com> writes:

> But the dreaded FXO/FXS issue. It's like trying to remember linear algebra.
>
> If I'm plugging the line from analog phone system into the 202, which
> then routes it to asterisk, I'm plugging the line into an FXS port ,
> correct?
>
> The line from the phone company is plugged into the FXO port. And
> since I'm not connecting the 202 to the phone company , I don't need
> one. Correct?

Yes, that's correct.

FX stands for foreign exchange, and the letter on a port denotes the
type of the thing that attaches to it.  So it's FX "S"tation and FX
"O"ffice.

The easy way is to note tht most VOIP adaptors (for non-PBX use) have 1
or 2 FXS ports, for plugging in analog phones, and a FXO port is less
usual.