In the aftermath of AT&T Inc. (NYSE: T)'s announcement of new mobile data price plans, the operator reveals that data used on its Microcell femtocell will be included in subscribers' newly capped monthly data allowance. (See AT&T Intros Mobile Data Caps, Capping the Data Gusher, 5 Mobile Apps That Bust Data Caps, and BillShrink: AT&T Data Caps Mean Paying Twice.)

First spotted by Current Analysis research director Peter Jarich, the news that 3G data traffic running over the AT&T Microcell will count towards a user's monthly data limits, just as making voice calls over the Microcell counts towards a user's monthly bucket of minutes, was confirmed by an AT&T spokeswoman. (See Femto Watch: Vodafone Means Business in Spain and AT&T's 3G Femtocells Now in More US Cities.)

It is possible to get unlimited calling on the Microcell for $19.99 per month, but this is only for voice calls, not data.

In contrast, WiFi usage does not count towards a subscriber's monthly data limit.

A pricing policy that includes femto usage in the data caps and not WiFi shows AT&T's preference for WiFi access. And in terms of offloading mobile data traffic from its busy 3G network, this policy also shows that AT&T's femtos take a back seat to WiFi. (See Deutsche Telekom Joins Rush to WiFi Offload and MWC Preview: Data Offload to the Rescue.)

Here is AT&T's position on the Microcell:

"The 3G MicroCell complements Wi-Fi by providing enhanced in-home voice coverage and reliable data when Wi-Fi may not be available -- but it is primarily intended for voice calls," said the AT&T spokeswoman in an email to Light Reading Mobile.

For consumers, the femto price model means that they will pay AT&T for the Microcell to get better indoor 3G coverage, pay for the backhaul connection to AT&T's core network, and pay AT&T to use that indoor 3G base station.

AT&T isn't alone here. Vodafone UK also counts voice and data traffic from its Sure Signal femtocell towards a subscribers' monthly voice plan and data limit. (See Vodafone Revs Femto Engine and Brits Get Femtos From July 1 .)

— Michelle Donegan, European Editor, Light Reading Mobile