[Asterisk-Users] CAS voice signalling?

[Steven Critchfield]

On Mon, 2005-01-17 at 16:53 +0100, Daniel Nyström wrote:
> Oh, thanks!
> How do I know which codec is used on Adit 600?

Oddly enough, I don't see any options in the Adit 600 manual for setting
the codec for the normal FXS cards, but for the FXS5G card it has
varying impedance settings. 

>From page 5-154 in the Adit 600 Release 3.2 manual
Index 1, 120 ohms + (.110uf || 820 ohms) A-law Norway.
Index 6, 220 ohms + (.115uf || 820 ohms) A-law Austria, Germany, Mexico,
Switzerland.
Index 8, 270 ohms + (.120uf || 910 ohms) A-law Finland


There are 19 listings, but only 3 of which are ulaw (Japan, Korea,
US/Taiwan).

> Does the server need to reencode it at all, or is the codec the same
> on Euro ISDN?
> If it has to reencode everything, it really seems to be CPU critical
> when using 30 FSX lines into 30 Euro ISDN lines.

>From ulaw to Alaw shouldn't be compute intensive, it shouldn't be more
than a bit munge. It isn't like there is any compression involved.

> Btw, when using Adit for connecting 30 handsets. Is it FXS or FXO
> modules I need? As I've seen, there is alot of misunderstanding in
> that particulary case.

FXS is for pointing at a station(phone)
FXO is for pointing at a office(telco)

For phones attached directly, you need FXS ports.


> ----- Original Message ----- 
> From: "Steven Critchfield" <critch at basesys.com>
> To: "Asterisk Users Mailing List - Non-Commercial Discussion" <asterisk-users at lists.digium.com>
> Sent: Monday, January 17, 2005 2:57 PM
> Subject: Re: [Asterisk-Users] CAS voice signalling?
> 
> 
> > On Mon, 2005-01-17 at 14:33 +0100, Daniel Nyström wrote:
> > > According to CarrierAccess, the Adit 600 uses CAS for voice signalling. What is this?
> > > This should not be a problem for Asterisk?
> > > Does the Asterisk server need to reencode CAS into aLaw when going to Euro ISDN?
> > 
> > CAS is Channel Associated Signaling. It isn't dependent on alaw or ulaw
> > it has to do with where the signaling bits are. 
> > 
> > Adit 600's are well known to work with asterisk. 
> > -- 
> > Steven Critchfield <critch at basesys.com>
> > 
-- 
Steven Critchfield <critch at basesys.com>