Thursday 19 January: VoIP and IP Telephony

VoIP and IP Telephony

Peter GradwellPeter Gradwell opened his talk with an introduction to the concept of IT telephony, briefly describing the best known players in the consumer market, including Skype, Vonage, freetalk from Dixons, Wanadoo, BT Communicator, and, announced that very morning, the launch of a new service from Tesco.

He described the hardware options:

  • for consumers, either a headset or dedicated USB phone that plugs into a PC
  • for businesses and more advanced users, either a special ethernet-connected IP phone, or a normal phone plugged into an APA (Analogue Phone Adapter) device connected to the network.
  • Internet rules apply – distance isn’t an issue

In principle, you can plug in anywhere and use VoIP.

In the UK, Ofcom had been persuaded to allow VoIP operators to assign geographic telephone numbers.
This means that, for example, a Londoner can have an Edinburgh phone number, and you can work from your spanish villa, whilst appearing to be in Birmingham.

Users in other countries are not as fortunate: German VoIP customers cannot have geographic telephone numbers.

Peter explained that while

  • individual VoIP users may be able to benefit from somewhat cheaper calls (depending on their call pattern and discounts offered by their telephone service provider), and
  • large enterprises probably already have sophisticated PABX systems and negotiated discounts from telcos,
  • Small businesses probably stand to make the easiest and most effective gains from VoIP.
    Using examples from his company’s customers, Peter explained how a small business, with individuals in different offices or home locations, can appear "joined-up". Internal calls are free, incoming calls can easily be routed between extensions if the first user does not pick up, or routed to several extensions at once for the first available user to answer. By the suitable use of geographic numbers, the business can appear to be local in several different areas.

Peter offered to supply more information: just sign up for ten things to consider about voip.

Ater the formal session and Q&A, members had a chance to look at some of the IP telephony equipment which Peter had brought with him, before repairing to the Lamb and Flag to continue the discussion.


VoIP slides (pdf)Peter’s slides are here and also linked from our downloads page.