These user errors are "a significant opportunity for the service provider," says Albert Gouyet, vice president of marketing for Nominum. "The end user gets more help from a carrier-branded search page, and carriers can use the service to monetize this traffic."

Nominum says it has four carrier customers for Vantio NXR -- two in North America and two in Asia -- that all have more than one million subscribers.

Gouyet says Web-redirection services should redirect only Web browser errors, not such as e-mail. He says that Web redirection services shouldn't degrade DNS performance, because of all the applications that depend on DNS. He adds that users should be provided the opportunity to opt out of Web-redirection services.

He says Nominum's Vantio NXR enables carriers to provide a better Web-redirection service by avoiding these problems.

"Nominum's underlying technology, called SureSurf, lets carriers determine what gets redirected and what doesn't," Gouyet says. "It has very fine-grained controls."

Gouyet says that Nominum's Vantio NXR is "night and day different" from VeriSign's SiteFinder. "VeriSign did this at the top-level domain, in a nondiscriminatory fashion, without an opt-out. Our solution is at the edge of the network, closer to the subscribers, and allows an opt-out. It does Web redirection more intelligently. It's a completely different value proposition."

Carriers are starting to reconsider the yearslong ban against Web redirection. For example, enabled a DNS redirect service last year.