Texas cities expand fiber networks

Texas cities expand fiber networks

paul palumbo

American Communications Services Inc. (acsi) is adding another 50-mile fiber deployment to its installation of about 120 miles of fiber plant in the Dallas/Fort Worth Metroplex. The $20 million network, expected to be brought online during the second quarter of 1997, was initially built with 60 miles of fiber backbone in 1995. However, higher bandwidth needs required the installation of a 2.5-Gbit/sec OC-48 system between Irving, TX, and Fort Worth, according to the company`s regional general manager, Shane Hampton.

Acsi, Annapolis Junction, MD, sells special access services between end-user tele communications businesses and long-distance companies. It connects into telephone networks at 622-Mbit/sec OC-12 rates and typically takes 155-Mbit/sec OC-3 capable facilities to the customer premises. Information from the premises can originate from various sources, ranging from private branch exchange banks to data output from computers (see figure on page 32).

Hampton explains that acsi can architect multiple local area networks into a wide area network that supports videoconferencing, desktop conferencing, and electronic mail across the enterprise. "A company like acsi has to continually comply with new Synchronous Optical Network (Sonet) standards," says Hampton, noting there have already been six software upgrades throughout its Metroplex networks since last year.

Acsi is presently using Sonet gear from Lucent Technologies and Fujitsu, including Lucent`s DDM-2000 and FT-2000, as well as Fujitsu`s FLM 150 and FLM 600 multiplexers operating in the 1310- to 1550-nm range.

Hampton explains that acsi also put an FT-2000 OC-48 ring between two SBS Communications central offices and the AT&T point-of-presence site in Fort Worth. He notes that AT&T buys capacity from acsi incrementally as it adds more customers in the area. Acsi is also interconnected with Sprint Corp. in the Metroplex.

Since interconnection was not possible with MCI in downtown Dallas, acsi co- engineered a 25-mile fiber ring with MCI Metro that interconnected with the carrier through an OC-12 point-to-point ring. Hampton explains that acsi is now looking to expand its fiber build into the Richardson and Plano, TX, markets.

"Acsi has to continually expand on fiber networks and take service where customers require it, or they`ll go someplace else," Hampton observes. The company targets cities with populations of 200,000 to two million.

According to Mark Roberts, an analyst with Montgomery Securities in San Francisco, "The fastest-growing markets for bandwidth are second- and third-tier cities in the South and Southwest because as telecommunications becomes ubiquitous, location becomes less important. And high-tech businesses, which are often telecommunications-dependent, are moving to areas of the country with milder weather and lower costs of living."

Fifty networks by 1998

Acsi currently has 24 local networks operating throughout the South and Southwest and is planning another 10 networks. "Acsi expects to have a minimum of 43 networks by the end of 1997, possibly as high as 50," says Dennis Ives, senior vice president for network development. The company interconnects with several regional Bell holding companies, including SBS Communications, BellSouth, and US West. The company just turned up its first revenue-producing customers for switched dial tone in Columbus, GA, says Ives. Networks in Florida and Oklahoma are slated next.

Acsi uses non-dispersion-shifted fiber from such vendors as Alcatel, Lucent Technologies, Alcoa, and Pirelli. The typical cable contains 144 fibers, with 12 fibers in each buffer tube. In networks running from the CBD node to the interexchange car riers` points-of-presence (and to some large end-users), one pair of fibers might be required for each system. The company may even dedicate an entire buffer tube to some interexchange carriers, according to Ives. "Acsi starts by illuminating just one or two fiber pairs with electronics, but as the business grows the company equips additional fibers to those same locations," he says.

Although the company`s fiber-allocation plan begins with two fibers, based on experience it reserves eight or 10 others for use with interexchange carriers. Five-gigabit-per-second OC-96 electronics, which have just been ordered for some systems, would be used to hook up a node in the CBD to a remote node. Acsi does not use wavelength-division multiplexing at present, but could do so if future expansion is threatened by fiber exhaust, says Ives.

Acsi links metropolitan networks through a coast-to-coast high-speed ATM data network. Its new ATM data networks use Newbridge 36170 Mainstreet ATM/frame relay switches, and Cisco 7513 routers to ship information at DS-3 rates of 44.736 Mbits/sec.

In addition to the Dallas/Fort Worth build, acsi has completed construction of the downtown portion of its fiber-optic network in Tulsa, OK. The entire network--a 50-mile, $7 million project--is expected to be completed by this summer. While local service is six months away, customers can immediately use the company`s fiber-optic network for business communications. q

Paul Palumbo writes from Seaside, CA.