In a class by itself

The next generation network must duplicate the functions of Class 4 and Class 5 switches to enable carriers to provide flexible apps and services

As the millennium approaches, telecommunications companies should prepare for tomorrow's network while reflecting on past achievements and the lessons they have learned. Issues demanding the industry's attention range from dramatic changes in technology to the operational challenges that both traditional and emerging players face.

This is because the industry is going through a "100-year" event in the evolution of its basic technology: the transition of its network infrastructure from circuit to packet switching. These new networks, often referred to as next generation networks, stand to change how carriers provision applications and services - and how customers access them.

The feature/software dilemma

The public switched network has come a long way from its cord board beginnings, evolving to electromechanical switches and, more recently, digital switches.

Today's public network, of course, is still voice-centric in nature, despite the fact that data traffic volume is now - for the most part - equal to or greater than voice traffic. The primary network intelligence is contained in Class 4 and Class 5 switches. Class 4 switches provide long-distance switching and network features; Class 5 switches provide the local switching and telephony features.

For years after the Class 5 switch became programmable, switch manufacturers wrote all the software. Therefore, any time a service provider wanted a new function or feature, it had to ask the equipment manufacturer to include the functionality in a future software release. To alleviate this problem,Telcordia Technologies and other companies developed the concept of the intelligent network and later the Advanced Intelligent Network (AIN).

This gave carriers - but not their customers - some ability to directly develop network functionality on outboard processors connected to the switches. Carriers often still had to wait for future software releases from the manufacturers before a feature could be added because the development of AIN still did not open all the capabilities of the switch. Instead, it inserted a small number of call triggers into the flow. And if a carrier needed a new "state change trigger," it needed to:

1. Get each switch manufacturer to agree to make the change.

2. Wait for each one to make the upgrade.

3. Purchase and install the upgrade for every switch in the network.

Incidentally, the switch manufacturers liked this situation and became dependent on the margins from this line of business. This partly explains why today's networks offer relatively little functionality to the end user, although the networks essentially are a large collection of powerful, interconnected computers.

Disruptive technologies

The Internet, of course, has proved to be a highly disruptive technology as its quality improves and its ease of use increases. What happens when the Internet meets the telephone network, whose voice services generate more than $200 billion in revenue annually in the U.S.? What happens when it meets broadband networks, such as cable and broadcast television, which also generate enormous revenue?

First, the Internet turns these services into applications. Second, the Internet evolves into a next generation network, which can provide broadband services in a high-quality, reliable and efficient manner.

The next generation network embodies two fundamental characteristics:

- It is a high-speed packet- or cell-based network capable of transporting and routing a multitude of services, including voice, data and video (Figure 1).

- It is a common platform for applications and services that is accessible across the entire network and outside the network by the customer.

The major physical components in a next gen network are routers, servers and edge devices on the customer premises. Class 4 and Class 5 switches are unnecessary. To place a telephone call over a next gen network, the customer dials the number the same as always. The edge device communicates the dialed number to the server, where call agent software determines the appropriate IP address for the call and returns the address to the edge device. The edge device then converts the voice signal to IP format with the given address.

If a service such as call waiting, caller ID or conference calling is used, the call agent software is called back into action to perform the needed functions.

It should be no surprise that another term for call agent software is the "Class 5 agent" because the software will contain the necessary functions of both Class 4 and Class 5 switches.

The call agent software also has an application programming interface (API) that enables carriers and third parties to develop applications that make use of the software's capabilities. This API allows for rapid development and deployment of new services in next generation networks, and its applications make use of core functions provided by the call agent software, including the ability to set up a call, perform voice recognition or add another party to a conference call.

Next generation networks are natural born data handlers. The next gen network routes Internet traffic with no intervention by any type of agent. Telcordia and its software partners are developing data agents to handle specialized data transmission needs, including guaranteed quality of service levels.

A watershed event

When the next gen network concept was presented to large carriers about a year ago, some initial reactions were, "Why bother?" Carriers thought their highly evolved Class 5 technology was working well and they were figuring out ways to handle the switch congestion caused by the Internet by routing the data around the switches.

The initial response to this question is that service providers can save a lot of money, with the added prospect that in the future, the new architecture will conform more closely to a Moore's Law curve (Figure 2).

While substantial potential savings certainly is worth a lot of attention and justifies the technology change for anyone needing to purchase new switches, it is not the reason to proclaim that next generation networks represent a watershed event in the communications industry.

The great potential that next generation networks offer telecom companies is the opportunity to reinvent themselves in the minds of their customers - to become a new category of service provider. The initial services that will be delivered over these platforms will replicate the services that Class 4 and Class 5 switches provide today. Therefore, proven communication services will provide the underlying revenues to pay for setting up the next gen network.

Once the next gen network platform is in place, a service provider will have a ubiquitous, powerful computing platform directly linked to its customers' communication and computing devices (Figure 3). It will be reliable and have full access to network-based information.

In a next generation network environment, service providers aren't constrained by the 3 kHz bandwidth limitation of today's networks. Voice recognition research indicates significant improvement in speech recognition rates at 7 kHz vs. 3 kHz. So in addition to the call agent software that performs Class 5 functions, it also is possible that a voice recognition agent will be included in the next gen network platform.

Intelligent appliances will access the next gen network to enhance their performance and capabilities. Next gen networks generally will become aware of individual customers' preferences and be able to conform to particular needs. Indeed, major carrier deployment of next generation networks may become the event that will cause network computing to become a reality (see sidebar).

The bottom line

The challenge that major carriers around the world face today is whether they can conceptualize this opportunity. If they can, their customers will perceive them not as simply providers of highly reliable, low-cost, low-value-added services, but as service providers that they trust with their information-based lives.

It won't be easy. Current telecom company brand images are solid and powerful, but they will have to evolve in the minds of their customers if service providers are going to fully exploit this opportunity. Powerful leadership will be required to achieve the transition.

Some will make it, and some will not and major market share shifts are on the horizon that will undoubtedly create big winners and losers. This environment is not one that the industry has been used to historically. But the nature of change is unrelenting, and the next generation network promises to help carriers survive.

Next gen network technology gives service providers the opportunity to build on their strengths by offering high value-added services over their core plant vs. playing catch-up through a series of ad hoc networks. Such offerings can include:

- Personal mobility services: Stuck in the airport with a delayed flight? Turn on your wireless personal digital assistant (PDA) and click "download voice and e-mail." The PDA identifies itself to the LAN in the airport and establishes a secure tunnel to the end user's mail service provider, downloading both voice and e-mail messages. After boarding the plane, the end user can plug the PDA into the airline seat's PC, respond to the messages and save those responses on the PDA.

- Service portability: Imagine being able to work anywhere as though you were in the office. The next gen network can store a large amount of information about the end user. Call agent software, in conjunction with an intelligent device, can allow end users to save and forward the user's profile and features from a phone or PC in the office to a remote location. With this type of open network environment, mobile workers would be able to transport all the features they have at home or office.