"They're going to employ quite a few people," said Arthur Pappathanasi, principle of the real estate trust that owns the 125,000 square-foot Clock Tower Building in Lynn, a former Philips Lighting factory rehabilitated last year into first-class office space with high-speed Internet access.

Lynn Development Director Stephen Harausz said the company's arrival could result in a significant economic boom for the city and its growing cyber district. He estimated Lightbridge will deliver 200 to 400 jobs to Lynn.

"A conservative estimate would be 250 jobs. They'll lease about 35,000 square feet. They obviously want to take advantage of the many other things that are going on here," said Harausz, referring specifically to the presence of 360 Networks, a Canadian company currently laying a transatlantic fiber-optic cable that makes landfall in Lynn.

Among the products Lightbridge offers are software packages that enable Internet-dependent businesses to link to high-speed telecommunications cables like the one under construction by Vancouver-based 360 Networks, and another planned by Asset Channels of New Canaan, Conn., which will hop port-to-port from Lynn to Miami.

Both fiber-optic cable systems are designed with terrestrial links and ultimately will transmit large volumes of data, securely, at searing speeds.

U.S. Rep. John F. Tierney, a Salem Democrat, said he proposed Lynn as a prospective site for Lightbridge after meeting the firm's top executives. "We were at a roundtable meeting when I heard Lightbridge was looking for space. That's when I told them what we had available in the Sixth District and put them together with the right people," he said, noting that company representatives soon met with Harausz, Lynn Mayor Patrick J. McManus and North Shore Community College President Wayne Burton.

"The mayor and (Harausz) immediately picked up the ball on this," Tierney said. "The college is also an important part of the training."

Burton, former dean of Salem State College's School of Business, created an incubator for startup companies at a former lightbulb manufacturing plant in Salem. The college provided internships and potential employees, a process that officials say could repeat itself in Lynn.

McManus said Lightbridge's decision to locate in Lynn was partly driven by 360 Networks' cable installation project and its selection of the North Shore city as a United States landfall. 360 Networks, formerly Worldwide Telecom, has been installing undersea cables to create a widespread telecommunications system. Earlier this year, 360 Networks built a switching station in the city.

The so-called 360Atlantic Cable extends north from Lynn to Nova Scotia, east to Ireland, and comes ashore again in England. The offshore cable laying is still under way. The Canadian firm committed to doing business in Lynn after local officials agreed to a public-private renovation of half of Munroe Street as a "cyber district" that would provide office space for computer-related firms. That commitment got an added boost this year when Lowell Gray, founder of the Internet service provider Shore.Net, sold his company to a larger firm, Primus Communications, and quickly announced it would expand to the Clock Tower Building.

"This building's reuse and the prospect of new jobs is great. It's everything we were hoping would happen as a result of the cyber district," said Lynn Area Chamber of Commerce Kevin Donahue.

Lightbridge is headquartered in Burlington and has offices in Colorado, the United Kingdom, Brazil and Asia. According to the company Web site, Lightbridge "plays a critical role in preparing telecom carriers as they face increased competition in a converging, highly competitive market."

The company purportedly can provide software, transaction management and consulting services that help telecom carriers quickly acquire customers and retain them over time. It is known for its credit-check and fraud-detection software products.

Gil Isenstein, a spokesman at Lightbridge, said the company has not officially announced plans related to Lynn. "It's still in the works. We're still ramping up," he said. "Nothing is set in stone in terms of what Lightbridge is doing. There's no timeline."

Lynn City Councilor David Ellis said the city has approved the company's request for a special permit to construct two antennae and a microwave dish.

"The people from Lightbridge told us they have wireless capability that is as fast as fiber-optic," he noted.

Besides rehabbed office space, parking lots and high-speed Internet connections, the Clock Tower Building leases at $18 per square foot, significantly lower than Boston's $80 rate.

"With all the improvements, that building is finally going to be a major employer again," said Ellis.