[asterisk-users] Asterisk as an analog call recording solution (was: Recording outbound analog calls with X100P)

[Matthew J. Roth]

Time Bandit wrote:
>> Is it possible to record outbound analog calls using an X100P?
>>
>> I was asked if I knew how to record all calls for a shop with 4 analog
>> phones transparently to the end users.  I thought Asterisk was a good
>> fit for this and I envisioned using either Digium TDM400Ps or Sangoma
>> A200s with 4 FXO and 4 FXS modules.  The FXO modules would be connected
>> to the existing PBX and the FXS modules to the existing analog phones.
>> Then with a simple dialplan, all inbound and outbound calls could be
>> recorded by Monitor.
>>
>> I wanted to mock this up using some X100Ps that I had laying around, but
>> found that I could only record inbound calls.  I believe that I need an
>> FXS interface to record outbound analog calls but my past experience is
>> with T1 interfaces, so I could be mistaken.
>
> Of course you can, if you have 4 FXO and 4 FXS, you could make a
> really simple dialplan and record the calls that pass through it,
> incoming or outgoing, and the users wouldn't even know that there is a
> pbx between them and the PSTN.
>
> You will need a lot of space to keep them all, but you could make a
> simple cron job that would erase any recording older then, say, 2
> months.
>
> Also, you would have the benefit of having CDR
>
> hth 
Thank you for the confirmation and the warning about disk space.

Now I need to decide between the Sangoma A20202 and the Digium TDM2411.  
I'm leaning heavily toward the Sangoma card for the following reasons:

- It doesn't require a 12V power connector for the operation of FXS modules.
- It is compatible with 5v and 3.3v PCI buses.
- It shares PCI interrupts properly.
- It maintains a single synchronous PCI interface for all FXO/FXS ports 
(additional daughterboards are added to a backplane bus connector)
- It has a better form factor.
- It is less expensive.

These are rather compelling reasons, but I'd still like some feedback 
from the list prior to making a purchase.

Both cards offer hardware echo cancellation for an additional cost.  Do 
the benefits of hardware EC justify the expense in this scenario?

Thank you,

Matthew Roth
InterMedia Marketing Solutions
Software Engineer and Systems Developer