Sprint's recent announcement of its new femtocell-based service, Airave, has many in the industry drawing the seemingly obvious comparison with T-Mobile's Wi-Fi-based service, HotSpot @Home. 

Before we throw the two contestants into the ring to duke it out, let's dig deeper into the motivations for Sprint and T-Mobile, the respective service offers and the underlying technologies. 

Steven Shaw

Fundamentally, the motivations for T-Mobile and Sprint are the same. There is a "battle for the building" under way, and mobile, fixed and VoIP providers are vying for consumer voice usage in the home and office. 

In this battle, the mobile operator is hampered by two basic issues. First, it costs more per minute to deliver services over the mobile network than over the fixed or IP networks.  Second, the performance (quality, coverage and throughput) of mobile services indoors is not always ideal. 

The mobile industry has dreamt of a low-cost wireless access technology that can be deployed in consumers' homes. The ideal solution would use an alternative, lower-cost, backhaul technology and provide a "home zone" within which consumers receive discounted mobile services. This solution would keep prices stable on the macro radio network and let operators offer discounted pricing where competition was fierce, mainly in the building. 

With that as a backdrop, there are some obvious similarities between the Airave and @Home services: Both offer subscribers unlimited calling when connected to the home access point; both services rely on subscribers' existing broadband connections to send mobile voice and data services back to the core network; and both provide a manageable home zone that is ideal for targeting competitors in the home. 

The concept of a home zone has been around the mobile space for some time. However, the importance of broadband and IP to lowering costs and improving the throughput of mobile data services has given rise to the next generation of home zone services being deployed by mobile operators to win the battle for the building. 

T-Mobile was one of the first to launch this next generation service with HotSpot @Home, and other operators with such a service include Orange (in France, U.K., Spain, and Poland), Telecom Italia, Telia Sonera (in Denmark, Sweden, and Norway), Cincinnati Bell, and now Sprint. 

There are some obvious similarities between Wi-Fi-based home zone service offers and femtocells. But digging a bit deeper reveals that each approach has its own advantages.

Access Points
Clearly with a femtocell-based solution, Sprint subscribers must install a new access point in the home. To help defray costs, Sprint is charging Airave subscribers $50 for the femtocell. 

The T-Mobile service, based on Wi-Fi, has a different challenge: how to handle cases where consumers may not want a new Wi-Fi access point in their homes.  With a 2-year service commitment, T-Mobile provides, at no cost, a new Linksys or D-Link Wi-Fi router optimized for the @Home service.  However, subscribers who don't want a new access point or a 2-year commitment may use the existing Wi-Fi access points in their home.

In addition, T-Mobile has enabled its hot-spot network (Starbucks) as a seamless extension of the service. Finally, @Home can be used with Wi-Fi access points in the office or other locations, including outside the United States.

Handsets
A significant advantage for Sprint's Airave solution is the ability for subscribers to use their current handsets. This should ease consumer acceptance of the service. 

@Home subscribers must upgrade to a new dual-mode handset with a Wi-Fi radio. While many people think of dual-mode devices as costly or bulky, T-Mobile's handset are reasonably priced ($50 with 2-year commitment) and stylish. Admittedly the selection is limited, but given T-Mobile's commitment, there are many new models in the works. 

Service Plans
Clearly, both companies are looking to displace landline usage in the home. For its part, the Airave service offer is quite aggressive, with unlimited, anytime calling from the home zone for just $15 a month. T-Mobile was slightly more aggressive with its initial @Home pricing, offering unlimited anytime calling over Wi-Fi for just $10 a month as an add-on service

The UMA Advantage
It is clear that mobile operators are looking to address the opportunity (and threat) poised in the battle for the building. Services such as femtocells and Wi-Fi/dual-mode handsets are the technologies of choice in this battle. However, given the various advantages and disadvantages, how does an operator decide which one to choose?

UMA (universal mobile access) is the 3GPP standard for extending mobile voice, data and IMS services over a broadband/IP access network.  As a generic access network technology, UMA is the de-facto standard for GSM operators delivering femtocell or dual-mode handset services. 

UMA's advantage for the mobile operator is clear. While a choice needs to be made between femtocells and dual-mode phones to address the battle for the building, UMA is the safe bet to deliver either service. The same UMA infrastructure can be used for both femtocells and dual-mode handsets, offering a level of investment protection. 

There is an ongoing battle for consumers at home. Services based on UMA technology deliver the competitive advantage required for mobile operators to be successful.

Shaw is AVP Marketing for Kineto Wireless