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Steve Shaw
Vice President, Corporate Marketing

Steve Shaw is vice president of corporate marketing for Kineto Wireless. Since joining the company in 2004, he has presented at industry and UMA-specific conferences worldwide and has been a key spokesperson for the technology. Mr. Shaw is a UMA blogger and a regular contributor of articles to global wireless and fixed-mobile convergence publications. view full bio
UMA vs. VCC
What are a mobile operator's choices for deploying a dual-mode handset service?
Different types of operators have varied motivations for bringing fixed-mobile convergence (FMC) services to market. Depending on the operator type and the service requirements, some technologies are more appropriate than others to meet operators' service needs and goals.

For operators contemplating an FMC service offer, two technologies -- UMA and VCC -- are most often considered for dual-mode handset (DMH) service. While often viewed as alternatives to one another, in reality, their capabilities are not entirely comparable.

UMA, also known as 'universal' mobile access, is a 3GPP standard defined by the mobile community to extend voice, data and IMS services over IP access networks. (Read "What is UMA technology? ")

The most popular application of UMA is for dual-mode cellular/Wi-Fi handsets. With UMA-enabled dual-mode phones, subscribers receive seamless mobility and handover between the GSM network and Wi-Fi in the home, office or public hotspot.

UMA is focused on delivering a complete 'mobile' experience (services, user interface, and capabilities) seamlessly to subscribers over the IP network. It is a solution for mobile and integrated (fixed and mobile) operators.

Voice call continuity (VCC) is an ongoing standards effort in the 3GPP. Estimates are that it should be completed (Stage 3) by the end of 2007. VCC uses SIP for call control. Because of this, its proponents say that a primary advantage of VCC is that it is "IMS-centric". Because VCC relies on SIP, the ideal candidate for a VCC solution is an operator which has already installed/invested in SIP/VoIP infrastructure for voice and is looking to leverage mobile services. Today, this is typically a fixed operator or the fixed division within an integrated operator.
How should operators choose between UMA and VCC? There are several evaluation criteria to be considered by an operator when selecting a technology for a dual-mode handset service. The first of these is the user experience. Does the subscriber have the same user experience on the fixed network as on the mobile network? If not, why not? With UMA, the user experience is exactly the same. All services (voice, packet, IMS) work the same on the GSM network and the Wi-Fi network (albeit packet services run faster over Wi-Fi).

For VCC, however, there are some glaring holes. VCC provides for 'voice' call continuity. There is no discussion of packet services continuity. Nor are there provisions for delivering supplemental services (SMS, MMS, ring tones) to subscribers when on the fixed network. It is clearly a different experience for the user.

While it sounds basic, the second item for consideration is the state of the standard and support for the standard. UMA was ratified by the 3GPP in April 2005. It is a mature specification that has been vetted through multi-vendor interoperability testing and commercial deployments.

VCC is still working through the standards process. While there are claims of products that are "VCC compliant," it is difficult to meet that requirement until the final specification is agreed upon. More importantly, no vendor interoperability can begin until the specifications are finalized.

Third, what is the state of the ecosystem for the technology? Are there handsets? Are major operators deploying? With UMA, there are handsets available today from the brands that consumers know and trust, Nokia, Motorola, Samsung, LG, BenQ and HP. For VCC, handsets are available from UT Starcom and Paragon Wireless; not exactly mainstream brands.

With UMA, Orange/France Telecom has deployments in their four largest markets (France, UK, Spain, and Poland). T-Mobile, Telecom Italia, TeliaSonera and British Telecom also have deployments.

There are no announced VCC deployments.
If UMA is so great, why is there work on a VCC specification? There must be some demand? The ideal candidate for VCC is an operator that has already installed/invested in SIP/VoIP infrastructure for voice and is looking to leverage mobile services. Today, this is typically a fixed operator or the fixed division within an integrated operator.

Fixed operators are using SIP/VoIP for fixed services and are anxious to find a way to stem the loss of voice revenue to the mobile network. Because these operators have an immediate and pressing need, work continues to develop the specification.

But within integrated operators, eventually a decision must be made to invest in the mobile network for voice services or the fixed network. In the future, will consumers use their fixed phone or mobile phone more?

Integrated operators like Orange/France Telecom, Telecom Italia/TIM and TeliaSonera have all come to the same conclusion: mobile is the future. UMA is the technology for mobile operators to accelerate fixed-mobile substitution.