Alcatel-Lucent (NYSE: ALU), Airvana Inc. , Cisco Systems Inc. (Nasdaq: CSCO), Ericsson AB (Nasdaq: ERIC), and ip.access Ltd. are understood to have submitted bids for AT&T Inc. (NYSE: T)'s rumored Enterprise Femtocell request for proposal (RFP), according to an industry source.

Light Reading Mobile reported in February that AT&T had launched a femto RFP focused on an enterprise-friendly version of the small indoor base stations. (See MWC Rumor: AT&T Eyes Q2 Femto Launch, Enterprise Suppliers.)

And AT&T has said the next step in its femto strategy -- now that it has commercially launched its residential Microcell service in the US -- is to consider how the tiny indoor base stations can be used by enterprise customers. (See CTIA 2010: AT&T Femtos Go Commercial in April, AT&T Takes MicroCells to Vegas, MWC 2010: AT&T Mum on Femto Launch Date, and AT&T on Track for Femto Launch.)

Now, though, it's thought that the scope of the RFP covers residential as well as enterprise femtocells.

If that's the case, AT&T's choice of supplier, or suppliers, could give it a second source for residential femtos.

Cisco is AT&T's current supplier for the 3G Microcell residential product, which is based on femto technology from ip.access. It's not currently clear, though, whether Cisco is bidding for the new business on its own, with ip.access, or with another femto vendor. (See Cisco, ip.access Prep Femto Combo and Cisco Claims AT&T Femto as Its Own.)

Ericsson, which has long sat on the femto sidelines, is understood to have taken a systems integrator role in its RFP bid. Its solution incorporates a product from 2Wire Inc. , which uses a femto module from Ubiquisys Ltd. The Swedish giant displayed femtocells from Airvana, Ubiquisys, and 2wire on its stand at the CTIA Wireless show in Las Vegas last month. (See CTIA 2010: New Product Recap, Ericsson: We Have Nothing Against Femtos, Ericsson's 3G Femto Issue, Femto Chips Too Costly, and Ericsson Stalls on 3G Femtos .)

Alcatel-Lucent and Airvana have clocked up some femto carrier wins of their own: Alcatel-Lucent supplies Vodafone UK 's Sure Signal femtocells; Airvana is a 3G femto supplier for Sprint Corp. (NYSE: S); and Japan's KDDI Corp. is trialing the vendor's 3G devices. (See Airvana Wins Major Sprint Femto Deal, Where Is the Sprint 3G Femtocell?, KDDI Tests Airvana's 3G Femtos, Vodafone Revs Femto Engine, and Brits Get Femtos From July 1 .)

— Michelle Donegan, European Editor, Light Reading Mobile