|
Enterprises have been awaiting the
arrival of dual-mode (Wi-Fi and cellular) handsets that can potentially
replace the traditional PBX phone. These dual-mode handsets can make
voice-over-IP (VoIP) calls over Wi-Fi, while retaining the functions and
benefits of a traditional cellular phone. With these dual-mode handsets,
workers only need one device with a single number.
The dual-mode handset effectively becomes the “work phone†and allows
unlimited mobile voice calls to be made at reduced costs over the enterprise
WLAN. When the user moves outside the enterprise campus, the dual-mode
handset works just like a typical cellular phone.
There are many options to choose from in terms of dual-mode handsets. Many
of these dual-mode handsets are based on PDA devices that require
proprietary client software to support seamless mobility between enterprise
and cellular domains. Although certain enterprises may tolerate the cost and
proprietary nature of these devices, others may find it is more practical to
consider other types of dual-mode handsets that can potentially have lower
price points and are based on standardized technologies. In the near term,
the only viable standards-based, cost-effective, dual-mode handsets arriving
in volume are those based on unlicensed mobile access (UMA) technology.
UMA technology became a part of the 3GPP standard in 2004 and has gathered
the support of all major handset manufacturers, including Samsung, Nokia and
Motorola. UMA-based handsets have form factors equivalent to today’s
cellular phones, despite being multi-radio devices.
UMA is generally considered a consumer-centric technology and not viewed as
a practical enterprise solution. One of the main reasons that UMA-based
dual-mode handsets have not been applied to the enterprise environment is
their incompatibility with enterprise IP PBX infrastructure. In its present
form, UMA technology relies on the cellular core network to provide call
processing and calling features to UMA handsets. As a result, enterprise
calling features are not available on UMA handsets.
Ideally, an enterprise worker should be able to use a standards-based form
factor dual-mode device such as the UMA handset as his “anywhere†office
phone. This means enterprise calling features such as call groups, extension
dialing, multi-ring and follow me should be accessible by the UMA handset
when in the enterprise environment. All existing enterprise IP PBX calling
features should be accessible on that UMA handset.
The UMA handset should become an extension to the enterprise IP PBX whenever
it enters the coverage of the enterprise WLAN. This way, not only does the
enterprise worker enjoy unlimited voice calls over Wi-Fi at reduced costs,
all enterprise calling features traditionally only available on fixed PBX
phones are now extended to the UMA handset. Once this is achieved,
enterprise workers need just a single handset for both cellular and
enterprise needs. Investment in fixed VoIP phones can be capped and
substituted by UMA handsets.
In order to achieve this type of enterprise feature integration, a new type
of network controller is needed to allow enterprise PBX infrastructure to
extend enterprise-calling features to UMA handsets. This network controller
would effectively allow the enterprise PBX infrastructure to provide call
control to UMA handsets, as opposed to the cellular core network. In doing
so, the UMA handset becomes closely coupled with the enterprise
infrastructure, allowing robust enterprise feature integration.
In addition, this type of network controller would also enable seamless
handover between enterprise WLAN and cellular network domains. This type of
solution should also address security and quality of service assurance
requirements of enterprise domains. Interoperability with enterprise WLAN
infrastructure is also critical.
Keith Higgins is Vice President of marketing for Stoke, Santa Clara,
Calif.
For more information:
www.rsleads.com/612cn-259
|