21CN is BT's 10 billion next generation network - an advanced national IP communications network for the future, BT have projected a phased rollout by 2010.

In the 21CN world, end-users will be able to access voice messages, data or video at any time on any device. It will be possible for users to share personal contact directory across their home phone, PC, mobile & PDA. And bandwidth will no longer be a consideration for most end-users as additional bandwidth can be requested as and when required.

Services based on the convergence of voice, mobility, video, data and content are now being developed and launched, using Sessions Initiation Protocol (SIP). These include, for example next generation television services. It puts the viewer in control by combining the appeal of TV with the interactivity of broadband. Customers will be able to watch what they want when they want and not be tied to TV schedules. Other services include a mobile phone service which switches to a broadband landline when the user arrives home or, for business users, at the office.

BT is planning to rebuild its phone network in the UK in a radical move that will cost billions.

It could change the way people use their phones and allow most people with a BT phone line to plug into broadband using computers, mobiles or other devices.

It could also mean that mobiles and fixed lines become interchangeable, with the same number and bill.

BT plans to convert the majority of its customers to the new network by 2009.

Undetectable

Customers who want to can switch to broadband themselves and plug any device into the network

Paul Reynolds, BT Wholesale

Dubbed the 21st century network, the technical work requires a gradual closing down of the old Public Switched Telephone network (PSTN) to make way for an internet protocol (IP) network.

BT will spend around 10bn on the project - more than the annual spend on Britain's main roads - and is hoping that a raft of new services will be possible on the back of it.

The switchover should be undetectable to its customers.

"We anticipate that millions of people will use the phone in the same way," said Paul Reynolds, chief executive of BT Wholesale. "But customers who want to can switch to broadband themselves and plug any device into the
network. The strategy is based on the idea of broadband everywhere," he said.

Savings

TIMETABLE OF CHANGE

2004 - fibre optic trial 2005 - Broadband available to 99.6% 2006 - Mass migration to IP network 2009 - network available to most customers

BT will begin trials of the IP network in 18 exchanges in London, Kent and East Anglia.

By January 2005, 1,000 customers will be connected. This will rise to 3,000 by June 2005 and major rollouts to all regions will begin in 2006.

BT believes the new IP-based network will be a lot simpler than the PSTN one and is hoping to make around 1bn saving per year by the time the network is complete.

Fast fibre

For the lucky few BT is also trialling the use of fibre instead
of copper, which will offer customers super-fast broadband speeds.

Around 1,500 customers in Suffolk, Milton Keynes and Docklands will be selected to take part in the fibre trial which will be up and running in the autumn 2008.

Despite speculation about the benefits of a ubiquitous fibre network, BT has no plans to lay it throughout the UK, concentrating instead on areas where new houses are
being built.

Matt Beal, the man charged with heading up the conversion to the 21st century network, admits that this could create a new digital divide.

"There is that risk but complete conversion is not possible," he said. He outlined some of the advantages of the 21st century network for customers. "They could set up
conference calls with their families, have video streaming
and voice-activated phones," he told BBC News Online.

Cheap calls?

Another advantage will be the ability to bypass the phone network entirely and make cheaper calls over the internet.

This could severely dent BT's revenues but the telecommunications firm is remaining upbeat, describing internet telephony as "an opportunity not a threat".

Mr Beal hinted, however, that the cheap broadband
telephony deals available at the moment may not continue. "The charging model of today may not be realistic in five years time," he said.

Session Initiation Protocol (SIP) is an open industry multi-media signalling standard.

SIP, will be used to connect IP devices all over the world.

Whilst most of the world is already connected to the internet, and has the ability to share data and video over the internet, most business telephone systems are not connected. Many companies have deployed Voice over IP (VOIP) services throughout their organisations, allowing free telephone calls across fixed links (such as broadband and MPLS services) for home workers and multi site offices, however at present, when it comes time to call a supplier, they have to use traditional services such as PSTN, or ISDN lines.

This is changing, eventually, most business and residential customers will be using an IP infrastructure connected to the internet, for voice calls as well as data & video. SIP is widely recognised as the standard which will enable interoperability between telephone systems from different manufacturers across this IP backbone infrastructure.

Using the SIP protocol, eventually all communications will be sent over an IP backbone infrastructure which will connect to the internet, and all IP devices.What essentially BT are doing with 21CN, is replacing all of their legacy infrastructure, the Public Switched Telephone network (PSTN) to make way for an internet protocol (IP) network.

In many organisations at the moment, all devices on their site are linked via Category 5 or 6 cabling, telephone systems, data networks, video, photocopiers, printers, security cameras, the list goes on. In the near future SIP will mimick this model, on a worldwide basis, we will be able to securely communicate with the people and devices we choose.

At Netco, we only sell systems which have the ability to add SIP trunks and extensions today, not the promise of SIP tomorrow, we do not have to wait for 21CN to develop, we can provide SIP functionality now.

• No need for you to install separate PSTN & data circuits at your office, we can install broadband links now which will enable you to have one link into your premises, should you want to call someone else outside of your company, you simply dial the number, one of our systems will carry the call at very cheap pricing
• Free calls between you and your remote offices & home workers
• Save money on line rental, no ISDN fees, installation or line rental
• Port a number from anywhere in the UK to anywhere in the UK
• Incoming presence for overseas and UK numbers, i.e. have a USA number which rings on your telephone system in the UK
• Support for multiple forms of real-time communication including voice, video, and instant messaging
• Future Proofing
• Savings using our SIP lines/ trunks

Historically, manufacturers have been selling digital display handsets from 100 - 150, and fully featured IP display phones from 150 - 200. If the customer wants a vast array of features, they had to buy handsets from the manufacturer at these prices, or just simply use an analogue handset purchased from high street retailers from 20 with the ability to hold and transfer calls, but little else.

The SIP protocol is changing this, SIP handsets can be purchased from as little as 35, and give more functionality than a standard analogue phone. Similar feature sets will be supported across different manufacturers, today, a digital or IP handset from a manufacturer may support over 700 features, whereas a generic SIP phone may only support 10 features, but this will improve, and how many of those 700 features will we actually use?

SIP Terminals (At last, one phone for all of your calls!)

For over 10 years, we, as a nation, have searched for the one device, (remember the hutchinson rabbit phone!) which can be a mobile device whilst out of the office, then work from your current phone system when in the office, saving money. A device which can give us emails, and voicemails on screen wherever we are. The device is now here!

Information is key in today's world, we need the information instantly, this is a combination of technologies, we can set any or all of this up for your organisation.

• Have one communications device whether you are inside or outside of your office, when you are out of the office, it is your mobile phone, when in the office, it is your in house phone, making extension to extension calls, and using the business telephone system to dial out
• View voicemails, emails & faxes in Microsoft outlook on your device, and play voicemails through your device
• One number for all of your communication
• Have forced emails sent to your device as and when they arrive
• Automatically synchronise any changes in Microsoft Outlook inbox, contacts, calendar & tasks, ensuring your Outlook folder is always up to date whether you are in or out of the office
• Surf the internet wherever you are, either over GPRS, 3G, or Wifi
• If you have a Wifi connection, use your device as an in house telephone, communicating free of charge with your company even in a hotel room, or coffee shop

• Over 25,000 different applications can be added to Windows Pocket PC, many free of charge, for more info, please log onto www.handango.com

SIP phone, which can be connected to any 'SIP' compatible phone system