Hi All

Been lurking here for ages, but this is my first post.

I run a small general IT services company with 5 staff.  Although I am technically competent, I have limited experience with Linux and no experience with Asterix or VOIP.
 

I would like to put in an Asterix based PBX system that can do the following:

1.  Incoming calls on our existing Analog lines (2 of them, 1 with faxability) are handled by the PBX
2.  Incoming callers get prompted to dial an extension number or hold for an operator.
3.  Incoming calls can be answered by anyone, transferred between extensions, put on hold, etc
4.  Unanswered calls go to a voicemail system
5.  All internal extensions are IP phones
6.  Outgoing calls can be directed over either the POTS lines or our ADSL connection to a SIP provider (i.e. press 1 for a POTS line or 2 for a VOIP line)
7.  We're able to make simultaneous outgoing calls on the SIP lines .
8.  We're still able to send / receive faxes
9.  The system is rock solid reliable and the quality of the VOIP calls is equal to that of the PSTN calls.

From the research I have done so far, I believe all this is reasonably achievable without too much aggravation.  I understand that I’ll need a TDM400P card with a 2 port FSO module to hook the PBX into the PSTN.

If I may, I’d like to ask a few questions:

1.  Is this all doable?  Are there any big holes in the list above or potential problems that I might not have anticipated?

2.  I plan to do this in 3 stages:
 a) testing / experimenting; 
 b) PBX and POTS lines only;
 c) PBX , POTS and SIP lines.
Does this seem a sensible approach?

3. While I’m testing, I’ll just use an old PC – Celeron 1.8 with 512mb RAM and a 40gb drive – it this spec going to work?

4. Again, while testing I’d like to use a softphone, preferably a free one – any suggestions.

5. Any other advice or suggestions will be most welcome!

6. Can you recomend a suitable SIP provider?

Thanks in advance

Dave