[Asterisk-Users] Qs about FXO/FXS cards

[Michael Graves]

On Sat, 1 Jan 2005 15:52:50 -0500, Nabeel Jafferali wrote:

>Hello.
>
>I am going to be putting together my first * system using FXO/FXS
>interfaces. All the systems I have set up thus far have been pure VoIP
>setups.
>
>The system I need to set up should have 3 FXO interfaces and 1 FXS
>interface, as well as several SIP phones. I have noticed people
>complaining about Digium's TDM cards - are these isolated incidents or
>are these cards unreliable? I intend to get the TDM400P with the
>necessary FXO/FXS boards - can I expect the installation to be somewhat
>straightforward? Any tips to avoid grief?
>
>Would it make more sense to get 3 cheap X100P's and use some kind of ATA
>for the FXS? Will obviously save a whole bunch of money, but will there
>be significant added complexity?

Here's an option that some might consider, especially in light of the
ongoing problems with virtually all small FXO interfaces....the Zultys
4x5 SIP phone.

This SIP phone includes an onboard 4 port router wit QoS and an FXO
interface. At point of introduction early in 2004 the FXO i/f was only
used as a lifeline. The firmware setup allowed the suer to pass local
calls to the FXO while passing all other calls to * via SIP.
Alternatively, the phone could try SIP calling outboard before falling
back to the FXO.

However, about two weeks ago Zultys released firmware that makes the
FXO available as a SIP reource to *. Calling coming in on the FXO can
be routed to * for transfer or VM purposes. 

It's a little strange since we're accustomed to having the FXO/FXO i/fs
on the server. However, you could bring the POTS lines to the desktops
and into the 4x5 phones. Then have the call pass to * when required.

BTW, the router functions such as DHCP etc can be defeated if desired.
Also, the 4x5, unlike some phones, requires only one registration to
support multiple call appearances. From on registration the 4x5 support
4 active SIP calls and one on the FXO, at the same time.

Michael

P.S. - I'm buying one of these from a friend who doesn't need his
anymore. I had it on loan for a month back in the summer. It worked
well with* but the FXO > * firmware was not yet available.

--
Michael Graves                           mgraves at pixelpower.com
Sr. Product Specialist                          www.pixelpower.com
Pixel Power Inc.                                 mgraves at mstvp.com

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