Planning for success

Converged networks for voice and data are on the road to dominance. They are not a majority of installations yet, but recent...

Converged networks for voice and data are on the road to dominance. They are not a majority of installations yet, but recent research by consultants MZA found traditional networks' market share falling rapidly - from 63% to 51% in the year to mid-2004.

At the same time, market share of voice systems with both traditional and IP capability grew from 35% to 47%.

In other words, around half of all voice systems are now sold with some IP capability. This is a major shift in the anatomy of voice and data networks towards single converged infrastructures that offer simpler and cheaper network management plus enhanced feature sets.

The simpler structure of the network can bring you cost benefits, but the increased sophistication of network equipment demands greater planning by your IT department.

Paul Taylor, sales and marketing director for network equipment provider Swyx, says most IT managers know the cost benefits of converging voice and data - reduced cabling and maintenance costs plus free internal calls between sites with IPT - but believes you can reap greater rewards according to size, operational needs and structure.

Reduced call charges

"It makes good economic sense for greenfield sites to opt for convergence, installing a single voice and data network rather than pay twice for equipment like switches, routers and hubs. Companies with multiple sites should also consider using a converged network with IPT, as they will benefit from reduced call charges."

Your business may have developed over time or have grown through mergers and acquisitions, so your IT department could find itself managing and supporting a number of different and disparate networks. Convergence can help simplify such tangled infrastructures, says David Atkinson, consulting systems engineer with Cisco.

"Networks can have widely varying service level agreements (SLAs), maintenance contracts and management interfaces, which add layers of complexity and cost to the business.

"To find greater cost efficiencies, improvements to customer service and higher productivity for employees, the totally integrated corporate infrastructure supported by a converged network has become the 'ideal' architecture for modern organisations," he says.

With IP systems, particularly those based on session initiation protocol (SIP), it doesn't matter where the server is in relationship to the telephone in use, says international market development manager for 3Com, Mike Valiant.

"With a converged network I can be at my company office in Santa Clara and log into the phone system and the setup will be as if I were at my usual desk. Anyone trying to reach me can do with my regular number. This becomes particularly useful when considering that a call from offices in the UK to the US will be routed as an internal call and be free."

There is a strong financial business case for you to look at converged networks, and you will likely find that such networks can bring significant savings in many areas - deploying new offices, maintenance, administration, internal voice calls and homeworking.

The simpler anatomy of the converged network makes financial sense and eases day-to-day management once installed, but because converged network equipment is much more complicated and the features on offer touch all parts of the business, implementation demands a great deal of forethought and planning.

Traditional networks handle voice and data separately and each type of network does its job well. The voice network ensures a circuit is opened between parties and communications are crisp and clear and not subject to delays and interference.

The data network ensures traffic gets from one network node to another in the fastest possible time that packets can be put together in the right order at their destination.

Converged networks carry all types of traffic; their equipment needs to be more sophisticated. It doesn't matter if it sometimes takes a little longer to download a web page but the same delay is not acceptable on a voice call, so a converged network is designed to carry a variety of traffic types, each requiring specified levels of service, such as availability, latency and jitter.

This is effected by "QoS-enabling" the local area network and wide area network so voice calls (or other important applications) can be prioritised, for example, by installing switches that are enabled for QoS.

The converged nature of the components makes voice and data networking a simpler matter than managing separate networks. But where it was an easy decision to simply buy a network that only carried voice traffic, converged networks - with so many features and functions rolled together - require greater forethought and planning, both technically and with regard to the business.

The first step in procuring and building a converged network is to perform a network audit. This will allow you to see what elements of the network need changing. Next you need to decide - with reference to the needs of the business - which core applications will be required, for example data collaboration, unified messaging or conferencing.

Then you can get on to detailed specifications. The services and applications the network needs to support and the location and needs of the users will define the specifications of the network. Virtual private networks (VPNs) are one example of where complicated choices have to be made, says Atkinson.

"If you need to connect a large number of distributed sites, nationally or internationally, an internet protocol (IP) VPN may provide the most cost-effective solution," he says.

"But there are several types of VPN to choose from, such as IP Sec, SSL and MPLS. MPLS VPNs provide effective any-to-any WAN connections and offer multiple classes of service to handle voice, standard internet traffic as well as high-priority or delay-sensitive traffic, such as for enterprise resource planning (ERP) applications. IP Sec and SSL VPNs deliver the greatest flexibility of access, for example for mobile workers, but do not support classes of service for different traffic types."

Of course, there is always the option of procuring a fully managed service, where the service provider will lease and manage the equipment and deliver the network with defined service levels.

But whether you opt for this route or do it in-house, it's best to know what is involved in moving to a converged network. The anatomy may be simpler than the networks of the past, but that simplicity hides a lot of detail and choices that must be made.

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