IP Telephony

Posted on: 20th April 2017

The earliest phone systems used point-to-point connectivity. Both of the handsets had to be physically connected end to end. Businesses could use their company’s structured cabling network to achieve this, but as they are not Ethernet based it couldn’t go through the LAN switches. You could connect the entirety of the phone system around the office using data cabling, which meant you didn’t have to implement Ethernet switches.

IP Telephony Ethernet CableTimes have changed since then and now most businesses use IP telephony. This means that you phone system uses your internet, via an Ethernet connection, to make calls and contributes to your used bandwidth. This is where VoIP comes into play.

VoIP (or Voice over IP) uses the IP network (the internet) to make calls rather than using a standard Private Branch Exchange (PBX) that the old telephone systems used. The lowest common denominator for IP calls is SIP. Session Initiation Protocol was designed to support the features of a telephone system. So if you wish to enter somebody into the call as a conference this will be done through the SIP. It is not limited to voice calling and can also be used with multimedia messaging such as video calls and instant messaging.

The alternative is PSTN (Public Switched Telephone Network). If you don’t want to mess about with analogue lines, which you don’t, then you take a PSTN approach through ISDN. ISDN can support multiple channels depending on your rental.

The main issue with IP Telephony is of course the reliability, or unreliability, of your internet connection. If you’re in a far off corner of the world that rarely has a great internet connection then IP probably isn’t the best option for you. Before switching to IP Telephony you need to make sure you have enough bandwidth to cope with the traffic. If somebody is sending a million emails at once and you’re talking to a client then your call could drop or your voice quality will decrease drastically. If you are worried that your broadband won’t be able to cope with all the calls there are ways to increase your connection, such as SharedBand.

There are a few ways around this issue, however. You could contact your local telecoms company which might provide an SIP connectivity package through their internet connection. This means that your service provider will control the traffic over your network and guarantee that you will have the necessary bandwidth for the calls you wish to make.

You could also create an extra ADSL connection that is dedicated to the voice traffic. Even simple ADSL links should hold enough bandwidth to manage all your daily calls.

If your business has multiple sites you will most probably want to connect all of the phones together somehow. You could go for an advanced WAN (Wide Area Connection) between your sites to carry data and voice traffic. A basic solution would be for each site to have separate PSTN connected entity. This is what allows you to shorthand dial. Typing in a few numbers to connect to a longer number. 

But what about the phones themselves? Do they take up to much room on your desk? Are the falling to pieces? What about the people who want to get rid of their physical hardware and resort to communicating online. 

The necessary steps to take towards getting rid of your physical phone are:

      • Implementing SIP capability
      • interface it to the PSTN
      • pick a communications server 
      • plan how your users will connect outside of the office
      • create a comprehensive directory service. 

In today’s day and age there are so many ways in which you can communicate with colleagues besides picking up the phone. Moving away from the physical phone means you will probably need some sort of application on your other hardware. If you are just looking for implementing voice technology then you could install a SIP compliant application onto all your devices (I.e. laptops, tables and mobile phones). If you want to go all the way and implement other forms of communicating like video calls and IM there are loads of applications out there which can achieve this across all your devices. 

Microsoft’s answer to this is/was Microsoft Lync. This has now become ‘Skype for business‘. Skype for Business brings together all of Microsoft’s well known application along with voice, video and instant messaging. 

When removing your phones you also need to think about your directory. This can tell your system how people’s different contact information links together. You also need to make sure that all the devices that are part of your phone network will register themselves on your network from any connection. you need to have the right firewall rules so devices can registers themselves securely and automatically from anywhere in the world. The best bet would probably be on-board certificates on the device to enable auto-registration.