Got the urge to converge?

The vision of a single network delivering voice and data to enterprise desktops has been like a mirage: it never gets any nearer and disappears if you look too closely. But the images of convergence may finally be more than thirst-induced fantasies. Susan Breidenbach reportsThanks to technology advances and emerging standards that are enabling a new generation of products, convergence is moving beyond call centres and other niches. The traditional PABX at corporate headquarters is in no immediate danger, to be sure, but small precursors to its ultimate IP-based replacement are starting to appear in branch offices.

The original premise of convergence - to save money by collapsing two network fabrics into one - is still valid, but the focus is shifting to the applications, enhanced communications and ease of management a single network enables.

Think about how frustrating it is to continually repeat information to successive customer service representatives when you call a courier service to check on a shipment and get transferred numerous times. A converged voice/data network turns voice into an application that can be integrated with database software so information to track the goods can move with the call. This means database vendors can start voice-enabling their products.

Such enhanced communications are increasingly critical in an Internet economy in which the customer is king and your competitors are only a click away. Also important is the ability to support a legion of mobile workers and telecommuters.

Because IP (Internet Protocol) is distance-insensitive, convergence will help employers cope with tight labour markets by letting people work from almost anywhere. With a single line, you can give home-based employees LAN access, Internet access, a PABX extension, voicemail and features such as speed dial.

Call centre operations are a primary beneficiary. Anyone anywhere on the enterprise network, including remote individuals attached via the Internet, can become part of a virtual call centre that works off a single database of customer and product information. Call centre managers will be able to create databases of incoming calls and at the end of the day send the five worst calls to the product managers, for example.

3Com's NBX 100, acquired through a merger with NBX, is helping define a new class of network server that functions as an IP-based PABX.

3Com, like NBX before it, has concentrated on providing a complete plug-and-play voice and data product to small offices that don't have resident IT staffs. While the target has been small businesses, large enterprises are starting to adopt iPABXs for branch offices.

Cisco has a competing product, acquired through its merger with Selsius Systems in October 1998. The system, aimed more at the enterprise than 3Com's NBX 100, is assembled from components that include CallManager call-routing software for Windows NT; two models of IP phones; and assorted gateway interface cards and routers needed for WAN connections. Cisco is now targeting smaller businesses with Media Convergence Server, a bundled version preinstalled in a server.

Cisco stays away from the iPABX label. A spokesman claims this term is "like calling cars horseless carriages", because convergence involves moving voice onto data networks while "iPABX" implies the opposite.

Vertical Networks, a start-up in the US, is challenging the two data communications giants. It offers a more completely integrated box, called Instant Office, that incorporates hub and router functions as well as IP telephony. However, Vertical doesn't deliver voice over IP to the desktop. Instead, it uses two wires - one to the PC and one to a traditional phone - from its box.

Moore's Law marches on

In their crafting of more fully integrated wares, iPABX developers are benefiting from faster and less expensive processors, better coder and decoders, single-chip Display Systems Protocols and standards stabilisation.

"There's been more combination of previously stand-alone devices - router, hub, switch, PABX, DSU/CSU - into a single platform," says Tom Jenkins, a senior consultant with TeleChoice. You don't get best of breed, but the integrated device is more reliable and easier to manage. Jenkins also sees more interoperability, due primarily to partnerships among equipment vendors.

The initial wave of iPABX platforms - including Lucent's first iPABX, scheduled for release before year-end - is aimed at small offices with less than 100 users.

Several of the traditional voice PABX manufacturers have scheduled enterprise-class iPABX systems for release in 2001, and Nortel Networks has promised one by mid-2000.

Evolution vs revolution

The question is, just how complete and scalable will any first-generation enterprise iPABX be?

Traditional PABXs have hundreds or even thousands of call-control features that have to be migrated from the highly disciplined and connection-oriented voice world to the anarchic and connectionless environment of data communications. How do you place a call on hold when it is just a bunch of packets that are mixed in with a lot of other packets?

Lucent expects traditional PABXs to host a lot of these call-control functions as iPABXs are adopted to support advanced applications that integrate voice and data.

"Most IP PABX vendors haven't even thought about doing things like call-detail recording or time-of-day routing," says Karyn Mashima, chief technology officer and vice president of strategy for Lucent's business communications group. "And scalability is always very hard to do in data networks, while voice PABXs are proven to scale to tens of thousands."

Lucent is adding IP trunks and features to its Definity voice switches so they can act as central servers and continue to handle much of the call control. Central and remote PABXs can communicate via IP, eliminating the need for costly comms lines.

Customers get a lot of the benefits of convergence while avoiding a forklift upgrade and retaining the traditional PABX's reliability and scalability. Of course, this approach leaves separate voice and data networks running to the desktop, supported by two different types of switches that have to be maintained and managed.

Start small

Convergence may not be ready for prime time on a large scale, but you shouldn't ignore it.

"You have to start looking at it now," says David Dines, a senior analyst with Aberdeen Group.

"Take a small branch office with an old phone system and turn it into a pilot site. Use the site to try to solve a business problem that you can't resolve cost-effectively with the old system, like using skills-based routing to send customers to the best available person in a distributed call centre. See how it works and impacts the network."

Companies should also look for "green-field" opportunities. One such example would be when a branch operation is being moved into newly built office space that has no voice or data network.

But make sure the equipment supports downloadable upgrades so you can accommodate new or evolving standards.

The LAN side reached a watershed this past year with the ratification of the IEEE 802.1p and 802.1Q standards for QoS (quality of service), and the list of products that support the International Telecommunication Union's H.323 specification continues to grow.

But H.323 was originally designed to deliver video over a single LAN and does not scale well to enterprise or carrier backbones. A better bet for a general call-control standard is the Megaco/H.248 specification being worked on jointly by the IETF and ITU.

Developers have not scheduled a completion date for Megaco; nonetheless, Megaco does appear to be supplanting the IETF's proposed Media Gateway Control Protocol standard.

Anyone looking to converge large voice and data networks should also ensure that the equipment they buy can be upgraded to support Session Initiation Protocol, a proposed IETF call-signalling standard.

Soft savings

Don't expect the iPABXs to cost less than the traditional devices they are replacing.

While analysts expect the prices to drop dramatically over the next year, you may pay a bit of a premium today. For example, one user says he spent about 15 per cent more when he decided to go with 3Com's NBX 100 instead of a Toshiba key system.

By consolidating administration and management, converged networks reduce operational costs, and they also make it a lot less expensive to move phones when employees change offices.

Moving a regular phone attached to a traditional PABX is labour-intensive and expensive.

In contrast, IP phones declare themselves using their Ethernet media access control addresses, whenever and wherever they are plugged in to the network. And because the same jack is used for voice or data, network administrators don't have to tag and keep track of different types of outlets.

On the negative side is the relatively high price of IP phones.

Also, IP phones will double the number of IP addresses that an enterprise is using, and they are subject to Ethernet distance limitations.

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More about 3Com AustraliaAberdeen GroupGatewayIEEEIETFInternational Telecommunication UnionLucentNortel NetworksSelsius SystemsTeleChoiceToshibaVertical Networks

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