[Asterisk-Users] FXO/FXS card

[Leo Ann Boon]

My comments below:

Luis Vazquez wrote:

> Respect to E1 channel banks: as stated by Marcelo E1 channels banks 
> are not a clear option because of high costs, I've searched the 
> internet and the lower price for these devices (with the FXO cards 
> included ) is U$2000 and above. Not acceptable for a deal with a 
> small/medium company with 6 to 12 FXO lines, lesser if you firt have 
> to buy the product to test if you are lucky and it works with Asterisk 
> (as is stated many times by mainstream asterisk developers E1 zaptel 
> drivers are much less tested than T1).

The biggest problem with channel banks is they only work with CAS 
(Channel Associated Signalling) systems not PRI. T1 lines in US are 
usually CAS, or more commonly known as robbed-bit signalling. E1, on the 
other hand, are mostly delivered as PRIs. There's no direct way to split 
a 30-channel E1 PRI into 30 analog lines, or combine 30 analog lines 
into 1 E1 PRI. The only E1 CAS systems I know of are R2/MF. Only a 
handful of countries in the world use R2/MF (I think only Mexico, China 
has moved away from R2/MF), hence the lack of support from equipment 
manufacturers.

A far cheaper solution is to use an E1 SIP gateway. Good ones are in the 
range of US$2,000 to US$3,000.

FYI.