Creating an ideal infrastructure for 'futuristic' services and applications

A wavelength-based fiber-to-the-home network provides a robust architecture for new service provision.

Mark McDonald
Marconi Communications

Service providers operating in today's dynamic, highly competitive e-world constantly face the challenge of meeting growing demand for next-generation multimedia communications services such as theater-quality broadcast-television video, office videoconferencing, customized TV programming, interactive TV, and video security. We've quickly evolved from a society that not so long ago communicated mostly by telephone to one in which the Internet, e-mail, and now two-way interactive video services have captured the hearts of even the most techno-reluctant consumers.

The desire for two-way, video-based services is expected to continue to gain popularity. In fact, some observers believe that in the not-so-distant future, people worldwide will want and expect to "see" the individuals with whom they are communicating.

Clearly, residential and commercial consumers want and need these "futuristic" services-now. The ability to meet this demand and add new services to a growing list of offerings at mouse-click speed is creating enormous competitive pressures.

Arriving first to market with an assortment of current and futuristic multitechnology services is a business strategy that offers whopping revenue potential. The attraction for service providers to offer a mix of video, voice, and data services to an ever-growing customer base is that they can double or triple their revenues within a very short period of time. In general, the more sophisticated the technology and the service offerings that they enable, the higher the revenue potential. For example, service providers deploying DSL technology can generate an estimated $60 a month per customer over and above traditional telephony service revenues. Fiber-based networks, the next wave of technology to tackle the Internet bandwidth issue, are expected to enable service offerings capable of generating $135 a month per customer, according to Forrester Research's Maribel Lopez, in the March 2000 report "Beyond Broadband."

Service providers eager to stay a step ahead of their competitors and meet demand for advanced communications services are implementing a mishmash of access technologies, including traditional copper-based networks, hybrid fiber/coax (HFC), direct broadcast satellite (DBS), and wireless local multipoint distribution services (LMDS) and multichannel multipoint distribution services (MMDS).

Asymmetric DSL (ADSL) and very-high-bit-rate DSL (VDSL), both copper-based technologies, are faring well in terms of enabling the high-speed delivery of basic data and some video services. With delivery speeds of up to 8 Mbits/sec at a distance of 18,000 ft, ADSL is a favored platform that continues to be adopted by proactive service providers across the globe. But with limited amounts of downstream and upstream bandwidth, ADSL may not be ideally suited for interactive, futuristic services such as high-definition TV (HDTV), office videoconferencing, or video security services.

HFC, a combination of coax cable and optical fiber, boasts robust downstream bandwidth capacity and offers service providers the ability to deliver a myriad of services, including interactive TV and video on demand. As services and applications such as HDTV require about five times the amount of bandwidth of a traditional standard-definition video signal, HFC may not be the optimal technology choice for competitive service providers seeking to deliver a rich selection of futuristic multimedia services. In addition, traditional HFC networks require special engineering to enable voice and upstream data services, and network upgrades will be required to eliminate upstream congestion or other quality-affecting variables.

Wireless access technologies such as LMDS and MMDS continue to be deployed by service providers requiring the flexibility to quickly deliver services to customers in a large geographical area. If greater coverage and/or bandwidth is required, service providers need only install additional equipment (i.e., antennas and base stations). As is the case with other access technologies, wireless is capable of supporting several existing high-bandwidth applications and services. It is also relatively inexpensive to add infrastructure to support new services or bandwidth capacity.

However, wireless may not be suitable for high-revenue, futuristic services. For example, wireless technologies are constrained by restricted bandwidth and by regulatory requirements associated with radio propagation.

In addition, since wireless technologies require a clear "line of sight" to enable service delivery, it may be difficult to serve customers in hilly and/or heavily tree-populated areas.

While existing technologies are to a great extent meeting the immediate needs of service providers, the question is whether they are powerful and flexible enough to allow them to move with the tide and continue to meet demand for futuristic services that require substantial amounts of bandwidth. To be poised for the future and sustain success, the reality is that service providers may need to upgrade their networks sooner rather than later. Deploying a powerful, highly scalable technology platform capable of supporting unlimited amounts of bandwidth will enable those willing to make the investment to meet demand for a rich selection of next-generation services and applications.

A potential and much-anticipated solution is a fiber-based network. Whether it's fiber-to-the-curb (FTTC), fiber-to-the-home (FTTH), or fiber-to-the-office, this long-awaited technology is clearly built for the needs of the 21st century. A fiber-based solution enables service providers to deliver in-demand, bandwidth-intensive communications services and add these services to a growing list of offerings at breakneck speed.

Enormous competitive pressures to deliver newer services faster and more efficiently is fueling demand for a vast assortment of multimedia services and applications that will enable businesses and consumers to communicate more effectively when they want and in the way they want.

To meet this demand and differentiate themselves in the marketplace, service providers require a robust, broadband networking solution like fiber technology, which offers unlimited bandwidth and the flexibility to meet customer demand for two-way, interactive, video-based services well into the future.

An FTTH/office solution enables service providers to offer a rich mix of communications and entertainment services, including carrier-class telephony, high-speed Internet access, broadcast cable TV, DBS TV, and interactive two-way video-based services-over a passive optical distribution network via a single optical fiber to the home or office. As well, an FTTH/office solution based on WDM, or a wavelength-based architecture, provides additional flexibility and adaptability to support future services.

With an FTTH/office solution, a single fiber typically terminates in the customer's home or office to a wall-mounted, optical-electrical converter (OEC). The OEC is capable of receiving multiple services offered on different wavelengths of light.

For example, it is possible to offer cable TV and DBS on one wavelength and telephone and high-speed data services on another. The OEC can be powered from the home or office with a battery backup that provides power to maintain essential services during power failures.

Voice, video, and data signals are relayed to the home or office from a passive optical splitter (POS) that supports several homes or offices, and may be located thousands of feet from the in-home/in-office OEC. A flexible optical link budget supports distances of up to 30,000 ft from the service provider's central office to the passive splitter, enabling the delivery of advanced services over a high-quality, futureproof, low-maintenance, unlimited-capacity medium.

So what does FTTH/office offer service providers that existing technologies do not? Perhaps the key differentiator is its colossal bandwidth capacity. As services in a fiber-based network can be carried on different wavelengths, service providers have the flexibility to deliver future services individually-as revenue streams warrant and faster than ever before-by simply adding another wavelength.

There is speculation that FTTH/ office's strongest rivals-HFC and wireless-will exhaust their capacity within the next five to 10 years. To avoid having to deal with this dilemma in the near future, deploying fiber deeper and deeper into the network may be the answer service providers are seeking.

The tremendous flexibility that fiber-based networks offer, as well as the ease and speed with which new, high-bandwidth services can be delivered via multiple wavelengths, can be illustrated by considering the complexity involved in adding a new high-bandwidth service to a traditional multiplexed network.

For example, if three-dimensional holographic video were to become the rage, this service would require huge amounts of bandwidth to be delivered to the home. To provide this service using a multiplexer-based network, the head-end multiplex unit would need to be upgraded. To provide the service to multiple subscribers simultaneously, the head-end multiplexer would have to run at several times the speed required to deliver service to a single customer. In addition, each and every home unit would need to be upgraded to run at this higher speed to be able to communicate with the upgraded head-end multiplexer.

This potentially costly and labor-intensive endeavor would undoubtedly result in service introduction delays. But if this service were to be delivered via FTTH using a wavelength-based architecture, it could be quickly added on a new wavelength. The original head-end would not be affected by this new service, and only users who want the service would need to have their home unit upgraded.

Demand for fiber-to-the-curb, -home, and -business is on the rise. Technology advancements in the area of WDM are expected to further refine and enhance this technology, making it a cost-effective solution to deploy. It is anticipated that breakthroughs in FTTC solutions will enable FTTH/office to be economically deployed before the end of this year.

The refinement and availability of FTTH/office is not operating in a vacuum. Forward-thinking vendors are working with a broad range of innovative fiber technologies that will effectively connect the access and backbone (i.e., local and long-distance) portions of the network, enabling service providers to offer end-to-end optical services to their customers.

We can expect to see the creation of a managed optical network, using "smart photonics" capable of routing and carrying informational services on different wavelengths. This all-optical network will arm service providers with the infrastructure they need to immediately capitalize on white-hot opportunities by adding new features and services at lightning speed.

The ability to react quickly and meet customer demand for high-bandwidth services will generate vast new revenue streams for service providers. An end-to-end optical network capability will clearly separate the winners from the losers in a marketplace that won't sit still.

Mark McDonald is vice president of access network marketing at Marconi Communications (Irving, TX).