Converged networks: The VoIP revolution

As the amount of voice traffic carried over the internet increases, Arif Mohamed investigates the pros and cons of moving voice and data networks to one converged network

Converged voice and data networks are revolutionising IT infrastructure. They offer IT directors the cost savings that come from using a single network, and at the same time preparing organisations for a new generation of applications.

According to industry estimates, 75% of worldwide voice traffic will use the voice over IP (VoIP) protocol within just a few years.

But many companies are asking whether it is worth abandoning their separate voice and data networks and moving to a combined one. Issues such as cost, quality, security and IT complexity still concern many chief information officers.

A converged network can run voice as well as traditional applications. It uses the internet protocol (IP) standard to send voice as digitised packets - termed voice over IP.

The network can also carry video streams, images, transactional data, e-mails, or any other information that can be digitised and sent over the internet.

The user can prioritise different types of traffic to maintain a high quality of transmission.

Eventually, such networks will allow applications to blend various kinds of data to carry out more advanced communications that pool, for example, voice calls with e-mails, instant messages, video conferencing and online collaboration.

One aspect of this is universal messaging, which gives the user a unified inbox. However, these applications are largely under development.

Nevertheless, many organisations are deploying converged networks for a wide range of applications. Organisations using converged networks range from public sector organisations, financial services institutions and other service firms, to retailers and manufacturers.

Most of the adopters are using VoIP as their main IP tool, but many are planning to use or piloting other emerging applications.

Accountancy firm BDO Stoy Hayward moved to a converged network earlier this year. It uses a network from service provider Teleware, based on Mitel IP3300 Gateway equipment and a multiprotocol label switching (MPLS) cloud-based network, to centralise network communication.

This allows staff to use a single handset and access their telephony-related applications from wherever they are. They can use an IP enabled mobile phone, Blackberry device, home phone, office phone or handset in another office to do this.

There are currently 700 staff using the converged network, which will eventually extend to cover a further 3,000 staff across the UK.

Graham Knight, the firm's head of technology, said, "The main use of the network is for mobility, to allow our employees to get their services wherever they are. We have in place access to your phone from the staff portal, so you can see your voicemail and the list of people who have called, as well as being able to set out your out of office message.

"The firm is a heavy adopter of mobile working - we have a real push to enable that flexibility across the business."

Knight added that there are drawbacks to supporting IP. The model BDO Stoy Hayward adopted requires it to maintain legacy analogue PBX equipment alongside the newer IP-based equipment.

"The main drawbacks are cost, integration and maintenance, as you have more than one platform. You have to balance the business benefits," he said.

Secondly, the costs of the new IP network are about the same as the legacy PBX-based phone system the company used to run, said Knight. However, he added that it is difficult to make a true comparison, because staff now have telephony functions they did not have before.

Fixed/mobile convergence has grown up alongside voice/data convergence. This describes the way traditional "wireline" telephones and mobile phones are coming onto the same datacentric network.

Graham Finnie, senior analyst at researcher Heavy Reading, said that by 2010-2012, "the boundaries between fixed and mobile technologies will be largely dissolved".

One of the business benefits of fixed/mobile convergence is the ability to give employees a handset that carries their office extension both in and out of the office.

They can access their contacts database and calendar from one handset, which reduces the cost of having systems for in and out of the office.

Converged phones also mean that firms can reduce their telecoms costs by routing fixed and mobile calls over an IP network when the user is in or near the office.

Mark Blowers, senior analyst for IT infrastructure at Butler Group, said, "When you go down to one network based on an IP infrastructure, the cost of ownership is often lower and organisations can make great savings on telecoms costs, because they do not have to pay a fortune to telecoms service providers for the calls.

"An IP-based infrastructure allows you to converge voice with the applications themselves. You can start to look at your business processes and transform those as well, integrating them with voice and data and messaging."

Eric Goodness, Gartner research vice-president, said IP telephony, IP contact centres and unified messaging were "leading-edge transformation initiatives" for networks. "The growing influence of IP convergence and the need to reduce IT-related spending shows the network is ripe for re-architecture and optimisation."

Leeds City Council

In March, Leeds City Council opened a multimedia IP-based contact centre, which rolled nine call centres into one. It uses an Avaya-based IP telephony system, which will allow residents to contact the council via phone, e-mail, fax or the web, said Paul Goode, the council's contact centre project manager.

The council is also looking into using video over IP to communicate with deaf citizens via sign language. The new contact centre will integrate into the existing Cisco local area network and wide area network, and Siebel customer relationship management and Blue Pumpkin call routing applications, and enable the organisation to use IP voice across its corporate network, vastly reducing its call costs.

Kent Police

Another user that has benefited from a converged network is Kent Police. It finished migrating to a single converged network in the spring, and implemented VoIP throughout the force.

It made financial sense for Kent Police to install one IP network for voice and data, and treat telephony as another application. It made cost savings from maintaining one network instead of two, and from a vastly reduced telephony bill.

Kent Police has 55 county-wide stations plus a call centre, and the phone remains the primary means of communication with the community. Its ageing infrastructure had developed performance problems, such as outages and incompatibility. The force decided to upgrade the phone system over three years and move to VoIP by implementing IP handsets at the small sites first.

Meanwhile, it retained its analogue Siemens PABXs and used bridging software to link to the IP network. This created technical difficulties at the larger legacy sites, but the force used Abridge translation software to maintain functionality across the two environments.

This shows that it is possible to buy IP-related equipment in an ad-hoc manner, and move from a legacy network and telecoms infrastructure to a converged network without replacing everything.

On the other hand, news agency Reuters went for the big bang approach when it moved headquarters. It chose to establish an IP network in the new building that would support large amounts of traffic.

It rolled out a VoIP network at its new Canary Wharf headquarters in 2005. In doing so, it gained the ability to stream TV to more than 250 displays and 2,500 desktops. The company installed plug-and-play broadcast TV-to-IP network distribution gateways, allowing it to stream digital satellite, terrestrial and internally produced channels across its voice/data network.

Reuters found it was experiencing quality degradation issues with its former, expensive coaxial system, said Matt Hassock, Reuters' technical operations manager.

He said the start-up costs of the IP system were greater than cable, but IP quickly becomes a much cheaper and more flexible system.

Forrester Research said that in 2005, 43% of European enterprises were evaluating, piloting or rolling out VoIP, IP PBXs and other IP services. However, this year, that figure is expected to rise to 54%.

Forrester vice-president, Elizabeth Herrell, said, "Enterprises have traditionally taken a cautious approach to deploying IP telephony and typically began deployments at smaller sites rather than at headquarters. Although adoption of IP telephony has continued to gain momentum each year, [2007] will see the most activity yet based on enterprise purchase plans. Many companies are now making enterprise-wide commitments to IP telephony."

Among the disadvantages that users and analysts have mentioned about moving to IP networks is the cost of buying IP equipment and IP-ready applications. The cost and complexity of integrating legacy network and telephony equipment is also of concern to IT managers.

The quality of service on an IP network has been the subject of debate too, particularly when it comes to VoIP. However, there are now many tools and technologies available to ensure that the quality of voice traffic is acceptable.

The security of a converged network is also an issue, because it carries all of an organisation's communication traffic, including voice calls, e-mails and application data.

In addition, moving from multiple networks onto a single converged network raises the risk of disruption to the business if something happens to that network.

Finally, new IP-ready applications such as collaboration, unified messaging and online interactive training require a change in the business culture, and acceptance from the teams within an organisation who will use them to work together.

Read article: Converged networks: The VoIP revolution

Vote for your IT greats

Who have been the most influential people in IT in the past 40 years? The greatest  organisations? The best hardware and software technologies? As part of Computer Weekly’s 40th anniversary celebrations, we are asking our readers who and what has really made a difference?

Vote now at:

Read more on Voice networking and VoIP