Networking

Vonage says Clearwire interfered with VoIP calls

As competition heats up Net-phone providers and traditional telecoms, blocked calls are becoming common.

Wireless operator Clearwire was one of two broadband providers causing traffic problems for Internet phone operator Vonage, a Vonage spokeswoman said Wednesday.

Vonage said last month that a cable operator, along with Clearwire, was suspected of blocking calls and not letting some home-phone adapters work appropriately. While identifying Clearwire, Vonage has not provided the cable operator's identity nor the exact cause of the problems. Vonage calls over Clearwire's network are now going through uninterrupted, but an issue remains with the cable operator, according to Vonage.

A Clearwire spokesman didn't immediately respond to a request for comment.

Blocked calls by design or technical error are becoming more commonplace for Vonage and other voice over Internet Protocol, or VoIP, telephone operators. The usual suspects are broadband providers, which view VoIP providers as unwanted hitchhikers on their networks. Because VoIP software lets any Internet connection double as an inexpensive phone line, Vonage and other "networkless" operators need only require subscribers to supply a broadband connection on their own.

Clearwire was created by wireless pioneer Craig McCaw. It's a small provider of WiMax wireless broadband service, and it operates in St. Cloud, Minn.; Abilene, Texas; and Jacksonville and Daytona Beach, Fla. WiMax is an experimental technology that promises to broadcast broadband at a radius of several miles.

The Vonage complaints in March were levied less than three weeks after a Mebane, N.C., telecommunications provider, Madison River Communications, said it would "refrain from blocking" VoIP calls and pay a $15,000 fine to the government. Vonage, a VoIP provider, brought Madison River to the Federal Communications Commission's attention and may do the same with providers involved in these latest problems.

The FCC had hoped the Madison River enforcement would help eradicate what's commonly referred to as "port blocking," a way of blocking traffic--one that telecommunications providers threatened by VoIP are turning to with increasing frequency. The FCC did not comment on Monday about the impact of the fine or about the Vonage complaints.