Small is beautiful: put a cell tower in your house

I could get way, way too technical here explaining all the signaling and interaction between a femtocell and a carrier's core network. But it's abstracted from the user experience, which is a good thing. So in order to use a femtocell, you just plug it into a broadband connection via Ethernet, follow a few simple steps in a manual, and unfurl up to 30 feet of antenna for a GPS receiver. Wait, what? A GPS receiver? That's the only part that you really need to know about.

The Femto Forum said that regulators

Saunders of the Femto Forum said that regulators and carriers outside of the US have opted in some case to eliminate GPS in favor of sniffing for macrocell identifiers nearby. They also can pull information from the broadband line that pinpoints the location. (Even a very weak cell signal can provide the cell IDs.)

You can see how tempting it would be to take an existing cell phone and use a femtocell while traveling internationally, plugging it into broadband to avoid roaming charges. But the use of those frequencies in this fashion is illegal in most countries, and could get you thrown in the pokey.

The company is testing

Cellcom's Riordan described several projects the company is testing, and hopes to roll out, including deferred SMS messages. He described a scenario in which his wife might think of chores and reminders for his 17-year-old son during the day, and she could send SMSes with a tag that defers them. When his son walks into the house, he gets a pile of messages on his phone, and his wife is notified that the messages were delivered.

Riordan said, "They all get sent to Rob's [his son's] phone when he walks in the door at the time he needs to see it." He added that the system could be configured to alert when other people enter, too, telling he and his wife when his son's girlfriend shows up at the house. (Andy Gothard of Picochip said this technology is nicknamed "the boyfriend sensor.")

Another project connects smart-home systems with femtocells. Riordan explained that he has a system that uses motion detectors to fire up lights and turn on the heat in his house. He's looking at extending this. "You walk into the house, and the motion detector turns on the lights," he said, but if the femtocell doesn't pick up his phone's association, "the motion detector sends an alarm that there's an intruder in the house."

Carriers may also pair home data plans with femtocell awareness. A carrier that allowed unlimited bandwidth on a home plan might allow a user to defer downloads over a 3G or 4G network until the user stepped within range of a femtocell directly connected to broadband.

Earlier this year, T-Mobile stopped offering a related service, @Home, which was most closely a competitor to Vonage, providing landline VoIP with unlimited domestic calling using existing home phones. Sometime after that, T-Mobile did away with its custom UMA plan and base station, merging it into the Even More calling plans, which include fairly cheap unlimited calling without a Wi-Fi restriction.