Network giant Cisco has taken a stake in femtocell vendor ip.access, endorsing the concept of indoor 3G base stations - but ip.access says that the technology faces most opposition in the enterprise.

Cisco has not given any details of the size of its investment, or any plans to adopt ip.access technology. Last year Google made an investment in Ubiquisys, another femtocell vendor - and one which Cisco was rumoured to be interested in.

Cisco's interest is likely to be primarily in the consumer space, where it can add femtocell technology to home gateways provided by its Linksys or Scientific Atlanta subsidiaries. Femtocells are predicted to have a $630 million market by 2010, according to Infonetics Research, but the business model and technology is still emerging.

At this stage, operators are trying femtos in secretive trials: ip.access is reportedly in trials with Vodafone, and it is working with Thomson on a home gateway. It also makes larger picocells, aimed at business, which are part of the low-power GSM product launched in the UK by operator PMN on spectrum auctioned by Ofcom last year.

"The stage we are at is lab trials and friendly user trials," said Andy Tiller, vice president of marketing at ip.access. "We're not at the stage where operators are talking about commercial launches yet." On Cisco's involvement, he would only say "Cisco is doing a lot in connected home already."

Tiller does not expect 3G femtos to replace Wi-Fi in the home, but he does believe they are a more natural way for phones to connect to the Internet, and to home networks as they use the phone's "natural" air interface.

In the office, Wi-Fi is a stronger competitor, he said, but "we're not really seeing it today. I've seen scepticism about whether enterprises will want to tune their Wi-Fi for mobile. We haven't heard people losing out to enterprise VoFi, although there are situations where that is being rolled out." Sites like New College Durham are the exception, he said, and only feasible where there is already a reliable Wi-Fi network with good coverage.

Cisco has toyed with femtos even before the name was coined - it bought a company called JetCell in 2000, which offered similar technology, according to Unstrung.