PSTN vs VOIP / SIP

VOIP / SIP Phone Systems vs traditional PSTN Landlines is the question I am often asked. It wast that long ago that if you needed to make 30 years ago. Traditional landlines haven’t really changed much since their introduction all those years ago. Wires from the local exchange are routed to your home and business either by overhead telegraph poles or in more recent years under the ground.

pstn vs voip

The reliance on physical cables or “wires” means that landlines by their very expensive to maintain.Some of these cables were laid over 40 years ago and cable technology has moved on leaps and bounds since.  If you wanted extra lines it meant an engineer visit and the costs associated with that. Lines could break, now this was uncommon but it did happen and if did you could be without a phone for days until an engineer came to repair it.

This poses some problems in that these cables were adopted to carry data services in the form of ISDN and later on ADSL.  Old copper cables combined the distance back to the local exchange meant that the further you were from the exchange the slower the data speed you were going to get. Sound quality was another factor. The sound quality on a landline is very poor even today.

BT’s ADSL modem from the 90’s

The game changer in recent years was when Fibre to the Cabinet or FTTC was introduced.  The UK government insisted BT Openreach who owned the telecoms infrastructure began to roll out super-fast broadband immediately. Green cabinets quickly appeared on the end of streets and this signalled that Fibre was finally in your area. BT was the first to market with its infinity product offering up to 80mb downstream.  But how was this possible given that it still used the same wires to your building?  The key difference here is that these green cabinets are connected to a Fibre-optic link back to the exchange. Unlike the copper wire which was used previously, Fibre can carry far more data than a copper strand over a far greater distance without any impact on speed.

 

 

Datacenters diversified to enter the new market

 

 

VOIP or Landlines: Conclusion, What’s best for Business? 

 

So where am I going with this. Now that we had a descent data connection to our home or business VOIP or “voice over the internet” along with SKYPE and WhatsApp became a new contender in the voice market.  Now VOIP has been around a while, I can remember that BT offered it to its broadband customers over 20 years ago but for some reason, slow connection speeds possibly it didn't take off. Unless you were a large company with a lease line or multiple ISDN lines. VOIP was not going to be an option for you.  Not that it required a load of bandwidth, the stability of the connection wasn’t that great with early broadband.  If the line went down, as it often did your phone didn’t work.

 

Openreach Cabinets mysteriously appeared on street corners almost overnight

 

Fibre to the cabinet, and its big brother FTTP “Fibre to the premises” are far more stable with a 99% uptime in a lot of cases.

The Rise of VIOP SIP 


Suddenly this opened a new market. VOIP began to evolve and a new protocol was introduced, “SIP”.  Now it was possible to have a reliable phone line without using the landline and the call quality was much better compared to traditional PSTN Landlines.

Traditional data centres who’s core business was hosting websites and email for customers, diversified in to SIP providers. They would host your SIP phone line and provide login details to tap in to a SIP phone and you were connected, using digital voice over the internet to make calls to landlines and mobiles all over the world.  You could even port over your existing landline number to them.

Software companies such as 3CX made it possible to have telephone features once reserved for major corporations for free, yes free.  You could have multiple extensions and a host of other features, even call recording on the Pro version.

3CX Phone Systems can be hosted in the cloud or on the premises using a PC, Linux or even low cost single board computer such as a Raspberry Pi.

A low cost Raspberry Pi loaded with 3CX Software can handle up to 100 extensions and 15 simultaneous calls over the internet which is mire than enough for most businesses and costs less than £50. Connect this with a Yealink phones such as the entry level Yealink T-19. If you want something fancy for the directors such as superb touch screen Yealink T57 your budget has to increase. However whatever phones you choose you will have a phone system that cannot be beaten in terms of value, features and cost of ownership.

That reminded me, “Simultaneous calls”.  Up to this point to have simultaneous calls you needed multiple landlines…. But I am going to leave that for the next chapter.