In the United States, AT&T limits Skype for iPhone calls to Wi-Fi connections. This means the VoIP app won't work over AT&T's 3G or EDGE data networks. ( says it got Skype to work on beta software, but it's likely that Apple and AT&T will close that loophole in a hurry.) In Germany, telecom giant Deutsche Telekom AG has prohibited the use of VoIP software for one and a half years. And in Canada, iPhone users won't be allow to download Skype due to "vague restrictions" in technology licenses, according to Skype. According to a , however, Canada's cellular providers may be to blame:

"Some have speculated that the holdup is due to resistance from Canada's wireless carriers, which rely heavily on revenue from conventional voice calling."

Wireless carriers have made it clear that they're simply protecting their turf. Cellular voice plans are big moneymakers, and providers don't intend to let low-cost VoIP upstarts like Skype take their business. But that argument doesn't wash. ISPs that offer home Internet access -- including Comcast, AT&T, and Verizon -- aren't allowed to cripple Net phone services like Skype and Vonage, despite the fact that VoIP providers compete with the ISPs' home phone plans.

The wireless carriers' actions clearly violate Net neutrality principles too. As summarized by Brad Reed of Network World, the , as outlined by the Federal Communications Commission in 2005, clearly side with the consumer:

"These principles state that networks must allow users to access any lawful Internet content of their choice, to run any legal Web applications of their choice, and to connect to the network using any device that does not harm the network. Additionally, the principles state that consumers are 'entitled to competition among network providers, application and service providers and content providers.' "