Telephony pt.1 – to PBX or not?
Traditionally, the decision to install your own Private Branch Exchange (PBX) was pretty simple. If you had more internal phones than outside (trunk) lines, then you needed a mechanism to allocate internal extensions to outside lines as needed. (Although another reason for having your own PBX might be to enable free internal calls, call transfer and call conferencing.) Initially, the line allocation mechanism was manual, your internal operator plugged you (literally) into an available outside line and you made your call. That was superseeded by automatic systems, usually requiring the entry of a digit (9 most often, sometimes 0) to request an outside line before the external number was dialled.
And that was how it stayed for many years, with gradual improvements in the capabilities of the PBX. And then came internet telephony, and the decision suddenly became a bit more difficult. Instead of having phone numbers delivered to your office either individually, or bundled in an ISDN package over an E1 or T1 line, you now had to add routing of calls via the internet into the mix. So, in theory, you could run your phone system without having to go anywhere near a trunk line, and it does happen.
The major new consideration (apart from the obvious opportunity to seriously slash your phone bill) is location. Before VoIP there was the option of having home workers appear to be in the office by hooking them up to a PBX hosted by your telephony provider. But this was not especially cheap, and as with any ‘old school’ PBX, changes were not easy to implement (many a telephony consultant has made good money simply by being able to administer a PBX). Now, however, using Voice over IP (VoIP) makes this scenario extremely affordable and flexible. Your remote worker with their IP phone (either a physical one or just software on their PC/laptop) hooked up to their broadband internet connection and connected to the central IP-PBX via a secure Virtual Private Network (VPN), can log in to their phone at home or at work and all calls to their DDI are routed to the appropriate place.
So if you are a growing business, and you want to have much more flexibility than the ‘one phone, one line’ model then it makes a lot of sense to consider VoIP. Right now the major players (Cisco, Avaya, etc.) are aiming systems at enterprise-level businesses, but there are options out there for SME’s, which I will discuss in Part 2.
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Looking forward to part II Colman… especially if it involves Hosted PBX services for SMEs. I’m interested in learning more about your perspective about VoIP and IP PBX within the the UK market.
Ben, glad you liked it. Part II will expand somewhat on hosted PBX services, but there is another option that I will be discussing too. Need to do a bit more background work first, though ! Stay tuned
[...] In telephony pt.1 I talked about the reasons why companies might consider installing their own PBX (Private Branch eXchange). Truth be told, this was typically a decision that was easily made when a company reached a particular size (where the cost of having one external line per internal phone was prohibitive). And usually a company would start with a pretty small, simple and, above all, cheap system that could support maybe 3 or 4 external lines and 8-10 internal extensions. For a budget of £1,000 to £2,000 you could be up and running, and if you chose wisely you could have some expansion capability too. For some companies this is still an easy and right decision to make. [...]
[...] 16, 2007 in Telephony, VoIP In Telephony Pt 1 I discussed reasons why a company might want to take control of their telephony by installing their [...]