Sprint taps Airvana for 3G, IMS-ready femtocells

In a filing with the Securities and Exchange Commission Wednesday, Airvana (NASDAQ:AIRV) revealed that Sprint (NYSE:S) has named it a 3G femtocell supplier, making the CDMA operator the first major customer to deploy the HubBub EV-DO femtocell. The deal also represents a possible turning point for Sprint, which could use not only to expand data capacity but as a means of integrating the femtocell into its next-generation services architecture.

Sprint was the first operator to launch a commercial femtocell service in 2008, but the service was limited to consumers and focused primarily on improving coverage, not adding capacity to the network. Samsung’s Airave femtocell was one of the first in the market, landing in both the Sprint and Verizon Wireless networks, but the femtocell access points and gateways were designed using proprietary protocols and the home base stations themselves contained CDMA 1X radios, limiting their scope primarily to voice services.

The much newer HubBub architecture carriers several enhancements that would allow Sprint to use the femtocell in fundamentally different ways as well as integrate the device with its IP multimedia subsystem (IMS) framework, a key to providing enhanced fixed-mobile convergence services particularly to enterprise and business users. The HubBub femtocell combines the functions of the base station, radio network controller (RNC) and packet data service node (PDSN) in to the same box. Hooked to a home broadband connection or a corporate LAN, the femtocell tunnels phone calls or data sessions over the public Internet to the operator’s core network, where the session is treated as if it were initiated on the macro network.

Since the HubBub supports EV-DO Revision A, Sprint can use the femtocell to greatly expand its data capacity since any IP service traffic from Web browsing to video sharing could be offloaded from the wide area macro network onto the public Internet. The HubBub and Airvana’s universal access gateway support a wide variety of protocols which can link directly to a legacy circuit-switched core, but most significantly to Sprint, the HubBub can connect via session initiation protocol, allowing it to communicate directly with Sprint’s IMS architecture. Though Sprint is only buying the HubBub femtocells, not Airvana’s gateways, SIP is a standard protocol so a HubBub femtocell could link to another vendor's broadband access gateway or session border controller (SBC).