The Ultimate Little Black Book

But Al Gidari, a lawyer representing wireless carriers, said other major telecom entities -- billing vendors, 911 emergency service providers and call center operators -- have databases the government might want to tap. "If the government wanted access to their databases, there are no clear procedures regulating that access as there are for phone companies," he said. "That's a danger."

NeuStar says trust is a significant part of its business.

"If we were to precipitously allow some overzealous law enforcement official access to data that has not been formally authorized by the courts, we are instantly jeopardizing our franchise," Ganek said.

NeuStar charges its client companies about 89 cents for every update to the ported number registry, about $500 to $1,000 a month for every common short code and about $5 a year for each entry in the Internet domain name registry.

NeuStar also helps optimize Web traffic for clients such as Amazon so that when a customer types in Amazon.com, NeuStar directs the request to one of Amazon's thousands of servers around the world. It provides the same kind of service for Oracle, Emirates Airlines and Forbes.

"We're at all the key Internet nodes in the world," Ganek said. "Depending on the time of the day and the point of origination, we send the traffic to Seattle, for instance, or to a data center in Miami or another data center in Singapore. If there's a fiber cable cut in the Pacific, we see it before [the carriers] do and turn the traffic in the other direction so it goes counterclockwise around the globe."

NeuStar helps maintain communication during crises. The Sept. 11, 2001, attack on the World Trade Center took out a large AT&T switch that served 50,000 telephones for the Wall Street area, Ganek said. Within a week, AT&T found another switching device, trucked it into lower Manhattan and installed it at a telecommunications facility at 60 Hudson St. As soon as the switch was plugged in and the green lights on the control panel were blinking, NeuStar, instructed by AT&T, went into its database and deleted the World Trade Center address for each of the 50,000 numbers and replaced it with 60 Hudson St., Ganek said.

"Within 10 seconds of making that change, anyone could dial those numbers and the calls were sent not to the World Trade Center, but six or seven blocks south," Ganek said.

About 70 percent of NeuStar's revenue comes from its ported number database. But as more communication takes place over the Internet, Ganek foresees a need for more Internet routing information services.

"It's just a matter of time before Google and AOL and Facebook and LinkedIn are all managing communications between and among users," Ganek said.

In 2005, the FBI and the Drug Enforcement Administration wanted a direct link to the database in NeuStar's Sterling headquarters, according to a January 2005 letter from the Justice Department criminal division to a consortium of carriers that have given NeuStar the contract to run the database. The department wanted to use the data to identify which carrier to subpoena for records concerning telephone numbers in an investigation, the letter said.

"What they were asking for in a nutshell was a copy of the database," said Mike Warren, NeuStar vice president of fiduciary services. "They wanted us to send them an update of the database once a day."

Instead, NeuStar set up LEAP, or Local Number Portability Enhanced Analytical Platform, a Web site to help local, state and federal law enforcement in investigations that rely on phone call surveillance. The database gives basic information such as carrier but not more technical details such as whether a phone number is for a wireless phone or a landline. Earlier this year, NeuStar added historical carrier information to that service.