Convergence /

IP telephony technology finding wider acceptance

By Carolyn Duffy Marsan
Network World, 04/30/01

An emerging technology called Enum that integrates the public switched telephone network and the Internet is becoming, well, enormous.

Enum lets users type a telephone number into a Web browser and find a corresponding URL, e-mail address or IP address. Six months after the Internet engineering community finalized the Enum specification, this simple but powerful concept has attracted a groundswell of commercial and regulatory interest.

The following Enum developments recently occurred:

Six IP telephony equipment and software vendors announced plans to support Enum in products due out this fall.
The U.S. government convened an industry advisory group that will issue recommendations in June on how best to deploy Enum.
And three U.S. companies - start-up NetNumber, dot-com registry VeriSign and telephone database operator NeuStar - are vying for the right to operate a central database of Enum registrations.

"It's pretty clear from any number of pieces of evidence that Enum is getting significant traction within the carrier and supplier communities," says Richard Shockey, co-chair of the Internet Engineering Task Force's Enum working group and an executive with NeuStar. "It's not a question of if Enum is going to be deployed, it's when Enum is going to be deployed."

That's good news for network managers interested in combining voice and data traffic over the Internet because Enum provides a much-needed service for connecting Internet telephone calls. Enum also offers the promise of giving employees a single point of contact for all their communications devices, including PCs, fax machines, handheld computers and cell phones.

"Whether you're running an enterprise or a carrier network, you're going to have to have Enum or Enum-like capabilities," says David Fraley, a principal analyst with Gartner Group. "You have to be able to convert a telephone number into an IP address, and that's the heart of Enum."

"I'm very, very hot on this technology," Fraley adds.

Fraley isn't the only one who is optimistic about Enum.

More than 400 companies, including network vendors and carriers, are participating in VeriSign's Enum test bed, which launched last December. VeriSign's free test bed, operated with the help of Telcordia Technologies, lets companies register real telephone numbers in 10 country codes.

Meanwhile, another 100 firms have joined NetNumber's free Enum trial since its launch last November. NetNumber has teamed with six vendors, including IP telephone supplier Pingtel and switch supplier NexTone Communications, to provide Enum support on products that will ship later this year.

NeuStar entered the fray last week with the announcement of its own Enum test bed. But NeuStar will only register trial telephone numbers, not real telephone numbers like VeriSign and NetNumber.

"We feel that unless you can properly authenticate and verify real telephone numbers, it's inappropriate to register [them]," Shockey says. "With Enum, there are legitimate issues of privacy and security that still have to be addressed."

All three test bed operators report that Enum works well.

"We have not encountered any surprises," says Lori Whitted, vice president of business development for VeriSign's domain name registry business. "Enum is working as planned."

While the technology is solid, Enum faces significant regulatory hurdles, including which federal agency will oversee deployment.

The Federal Communications Commission regulates telephone numbering, while the Commerce Department handles the Internet domain name system. The State Department, which manages the U.S. government's relationship with the International Telecommunications Union, convened the ongoing industry advisory group.

The advisory group agrees that the U.S. should move forward with Enum but has one major point of contention: whether more than one company can operate the main - or Tier 1 - database of Enum registrations.

Only one database exists for telephone numbers, which NeuStar operates under contract for the U.S. government. But VeriSign argues that competition for that database should exist similar to the registry/registrar model used for domain name registrations.

"The technology of Enum is relatively simple, but the politics are relatively hard," Shockey says.

Industry observers expect Enum to surmount these political hurdles and being being deployed in enterprise networks as early as next year. Indeed, many multinational firms are already testing Enum services with NetNumber.

"Voice over IP is coming on strong," says NetNumber CEO Glenn Marchel. "It's clear that Enum is going to play a central role in that architecture as it's developed and deployed."

IP telephony technology finding wider acceptance

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