AT&T: Lawful intercept reason femtocells subject to data cap

AT&T (NYSE:T) gave more detail regarding why it includes data traffic coming from its 3G Microcell femtocell in the overall data cap ATT's 3G Microcell femtocellthat applies to the operator's new smartphone plans.

During the Femtocells World Summit, Gordon Mansfield, AT&T's executive director for radio access networks, revealed that the carrier's national rollout of the 3G Microcell is now complete, meaning customers across the U.S. can now buy the home base station. The femtocell is marketed as a voice coverage tool, and Mansfield explained that the data traffic is capped because the femtocell traffic travels over AT&T's core network. Mansfield said AT&T isn't allowed to divert or offload femtocell traffic away from the core network because it has to adhere to the lawful intercept regulations to law enforcement agencies.

Instead on the data side, AT&T is encouraging users to offload their data traffic onto WiFi, which doesn't count toward the data cap. Mansfield said the majority of households have WiFi and all of AT&T's smartphones include WiFi. In addition, he said the latency was better on WiFi than on femtocells.

"Today, femtocells really are using a significant portion of our network," Mansfield was quoted as saying in Light Reading Mobile. "With WiFi, traffic goes straight from the access point on to the Internet. Femto traffic goes via a VPN tunnel straight to our network and to our core and then to the Internet."

Mansfield indicated standardization work underway to develop a way to offload femto traffic from operators' core networks. AT&T is trying to figure out whether its interpretation of the FCC's lawful intercept rules do in fact apply to femtocells. Under the FCC's lawful intercept rules, any mobile traffic that begins on license spectrum must pass through an operator's core network and be managed by the operator. So this would also include femtocell traffic.

Could this mean that using femtocells as a data offload strategy could be stymied? "Regulation is still a big hurdle and may significantly reduce the proposition of femtocells," Stuart Carlaw, vice president and chief research officer with ABI Research, told the publication.

For more:
- see this Light Reading Mobile article

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