Business Telephone System – Overview

A brief look at how the telephone phone systems work

We don’t want to weigh you down with unnecessary and in depth explanations of how each phone system works, but we understand that it’s good to know the basics. So, we’ve put together a brief outline of what each one entails.

Digital

Digital technology replaced the original, single copper analogue telephone system with two Integrated Service Digital Network systems known as ISDN2e and ISDN30e. The difference between the two is that ISND2e is presented in pairs (2 lines) and ISDN30e is presented on a bearer with a minimum of 8 lines and a maximum of 30.

If you were to buy a digital phone system you can expect a set up of digital handsets, wired phone lines and a central telephone system box.

Here’s how it works:

  • The digital handsets sit in bases that are connected to phone lines.
  • These phone lines then run from your base, through a wall and into a dedicated area within your premises; this area is usually classed as a server room and houses all your telephone, internet and IT equipment.
  • The bulk of your telephone system lives in this server room in a telephone system box that is generally wall or rack mounted.
  •  You will have one of two types box, a PSTN box (Public Switched Telephone Network) or a Patch cabinet.
  • The PSTN acts as a switch board and is connected via telecoms cables.
  • The Patch Cabinet has CAT 5 E structured cabling, used for both voice and data, that runs from a double outlet that is located on the wall by your phone. The cabling from the outlet connects back to the server room and into the Patch Cabinet (a large box approx 12 by 18 inches). This cabinet contains a panel and strip that links to all the separate phones in your office, it is the final destination for each phone line to plug into.

SIP

Session Initiation Protocol (SIP) telephone systems are a modern replacement for large digital phone networks. SIP is the method used to carry voice, over an IP (VoIP) network and this IP (broadband) connection is the differentiating factor between SIP and digital phones.

With SIP phones the set up includes, IP handsets, virtual and wired phone lines, a router and a 2 telephone system boxes.

They create your phone system in the following way:

  • The handsets, which may be desktop phones, wifi mobile phones or soft phones in a computer, each connect to an IP router. Desktop phones are wired, where as mobile and computers use virtual lines.
  • The IP router and the IP phone lines run from their bases to a double outlet and then through a wall to a Patch cabinet via CAT 5 E structured cabling.
  • However, if you don’t have an IP compatible phone system you will need a Gateway box to make external calls for landlines and mobiles; this box is plugged into the router and connects you to the public telephone network.

Hosted

Hosted telephone systems use Cloud and IP technology, and are the next step up from SIP systems. They are hosted virtually and rented out on a per user basis, saving companies the initial outlay of a telephone system. Today, they are the simplest, cheapest and most flexible of the telephone systems.

The tools needed to set up a hosted telephone system are IP handsets, a router and a box.

They create your phone system in the following way:

  • The handsets (desktop phones, wifi mobile phones or soft phones in a computer) each connect to an IP router.
  • As with SIP phones, the IP router and the IP phone lines run from their bases to a double outlet and then through a wall to a Patch cabinet.