CASE STUDY: Windsor Telecom PLC - Unified Communications Solution

DATE: JAN 2008

AIM: To demonstrate a proof-of-concept fully functioning VoIP PBX with extensible Unified Communications functions.

 

As Windsor Telecom looked to become a carrier-agnostic telecoms company, I told one of the directors it was possible for Windsor Telecom to become truly carrier and supplier agnostic by offering our own in-house solutions using Unified Communications with an open-source PBX.  I was then tasked to "put my money where my mouth is" and demonstrate such a system.

The solution had to offer:

• Call control and multimodal communication (IVR, voicemail etc)
• Presence
• VoIP, PSTN and Mobile Integration
• Instant messaging
• Unified messaging
• Speech access and personal assistant
• Conferencing (audio, Web and video)
• Collaboration tools
• Mobility
• Economy/Value

I decided upon Asterisk Open-source PBX as the main system of call control.  The main technologies to be used in VoIP would be SIP and XMPP.  I decided for this demonstration system to handle the SIP account management and authentication with Asterisk for simplicity, but in a production system I would move this to a dedicated SIP management/authentication server.  Connection in to and from the PSTN (Public Switched Telephone Network - the "classic" or "legacy" phone system) would be via the X100P hardware.  Presence and collaboration would be handled by XMPP.  Mobility/Mobile integration would be initially done using SIP.  Instant and unified messaging would be provided by XMPP and SIP with the use of SMS gateways.

I had a VoIP-PSTN proof-of-concept working within a week, using nothing but my lunch break and bits of spare time here and there.  I completed a working example that fulfilled all of the above bullet points after about 6 months of tinkering during my lunch break and during rare quiet times, or if I had 5 minutes while waiting for a piece of software to compile. I couldn't estimate total number of hours spent.

The test system/PBX was still working faultlessly when I left the company in September 2008.

Windsor Telecom have gone on to offer a successful Unified Communications solution for their customers, which they are still supplying to this day.

 COSTINGS/BUDGET:

System/PBX hardware cost:

Old employee workstation PC, obsolete -- £0

Software cost (licenses, support, ICO):

Debian or Fedora Core Linux O/S -- £0

Asterisk Open-Source PBX -- £0

Additional costs:

Digium (later Sangoma) X100P PCI PSTN FXO Interface Card -- £20

TOTAL COSTS FROM DESIGN TO IMPLEMENTATION:

£20