Optical/IP Networks

Fixed/Mobile Handover Vexes Carriers

Major carriers all over the world are launching fixed/mobile convergence (FMC) voice services that enable customers to place calls over mobile networks and WLAN access points using the same dual-mode wireless handset, yet many of them can't hand over calls between the two different networks.

That's one of the findings of a new Heavy Reading report, "Wireless VOIP & the Future of Carrier Voice Services," which analyzes the market forces that are driving dual-mode service launches, and examines the FMC services already commercially available.

Technology is starting to come to market that addresses those handover issues and meets the IP Multimedia Subsystem (IMS) requirements of fixed and mobile operators.

The report finds that while FMC services based on UMA (unlicensed mobile access) technology enable calls to be handed over between WLAN and mobile networks without service interruption, Singapore Telecommunications Ltd. (SingTel) (OTC: SGTJY) and French carrier Neuf Cegetel Group (Euronext: NEUF) have deployed technology that does not allow call handover in either direction between mobile and WLAN networks, while T-Com , the domestic fixed-line unit of Deutsche Telekom AG (NYSE: DT), and Norwegian operator Hello AS have deployed technology that supports cellular-to-WiFi handover, but not WiFi-to-cellular.

"Most new dual-mode services are not based on UMA and therefore don't support two-way handover between cellular and WiFi modes," writes the report's author, Heavy Reading senior analyst Patrick Donegan. "Handover is currently the subject of intense negotiations between wireless and wireline carriers, as well as internally within integrated carriers, but it will likely be several months before any common approach to handover emerges in the case of these non-UMA solutions."

Carriers that have implemented UMA solutions are BT Group plc (NYSE: BT; London: BTA), which launched its Fusion service in June 2005, and Orange (NYSE: FTE)'s Orange SA (London/Paris: OGE), which recently launched its Unik offering in France based on Ericsson AB (Nasdaq: ERIC) technology. FT also plans to launch in the U.K., Netherlands, Poland, and Spain, where it has mobile and broadband operations. (See Orange Launches Unik and UMA Services Near Reality.)

BT's service, which has about 30,000 users, only enables a Bluetooth connection between the dual-mode handset and the home wireless router for low-cost calls within the home or office, but the carrier is set to launch its cellular/WLAN convergence service within the next few months. Its service is also based on Ericsson technology, with Alcatel (NYSE: ALA; Paris: CGEP:PA) as lead integrator. (See 75857 BT Unveils Enterprise FMC, BT Offers New Fusion Phone, and BT Goes Blue.)

T-Mobile US Inc. is due to launch a UMA-based service before the end of this year, using technology from Alcatel and Tekelec .

UMA provides two-way handover, but Donegan notes that neither that technology, nor any of the other current dual-mode solutions being used, are wholly compliant with the IMS standard.

"While IP Multimedia Subsystem (IMS) is seen as the ultimate architecture for enabling multimedia fixed/mobile convergence (FMC), it is gaining relatively slow traction in the market," notes Donegan in his report.

Vendors are working hard to redress this situation, though, by developing technology based on Voice Call Continuity (VCC), "the standard being developed in 3rd Generation Partnership Project (3GPP) to facilitate two-way handover from 3GPP R7 [Release 7] of the IMS architecture," notes Donegan.

However, IMS R7 won't be widely commercialized before 2008, writes the analyst, and carriers want handover solutions now. As a result, "there is intense activity in the vendor community around developing handover solutions that are as compliant with the nascent VCC standard as possible," with specialist vendors such as BridgePort Networks Inc. , Cicero Networks Ltd. , FirstHand Technologies , LongBoard Inc. , NewStep Networks Inc. , and Outsmart Ltd. developing such technology. (See Bridgeport Shows Off at 3GSM, LongBoard Finds Partners, and NewStep Intros CSN30.)

Large vendors are also starting to announce VCC-compliant products. UTStarcom Inc. (Nasdaq: UTSI) and Nortel Networks Ltd. have already made announcements, while Huawei Technologies Co. Ltd. has just announced what it calls the "world’s first commercial IMS VCC solution," though company officials declined to say whether it was currently available for carriers to test and trial. (See Nortel Enhances IMS and Huawei, E28 Team Up.)

The next few months should see announcements from other major players such as Lucent Technologies Inc. (NYSE: LU) (soon to be Alcatel Lucent) and Motorola Inc. (NYSE: MOT), reports Donegan.

— Ray Le Maistre, International News Editor, Light Reading

Star Man 12/5/2012 | 3:34:16 AM
re: Fixed/Mobile Handover Vexes Carriers IMS and UMA services continue to be tested and announced by carriers and they are rolling out them worldwide. In my dealings with carriers it is surprising how fast they are moving aggressively forward in their spending to upgrade their networks for deployment of these services. Consumers and Enterprise customers will soon be offered IMS and UMA features from several major carriers in the U.S.

takayoshi3 12/5/2012 | 3:34:07 AM
re: Fixed/Mobile Handover Vexes Carriers Could someone clarify what this statement in the article means?

"Most new dual-mode services are not based on UMA..."

I'm confused. The definition of UMA is unlicensed mobile access, which includes all unlicensed wireless technologies such as Bluetooth and WiFi. Within the context of the FMC, dual-mode does mean GSM and WiFi (or Bluetooth), doesn' it? Then the above sentence makes no sense to me.
IPobserver 12/5/2012 | 3:34:06 AM
re: Fixed/Mobile Handover Vexes Carriers You can get the full definition of UMA here: http://www.3gpp.org/ftp/Specs/...

But quickly, not all dual-mode phones are UMA.

So for example, I have an application called TruPhone running on a Nokia E61 here on my desk... It lets me make and receive VOIP calls over WLAN... seems to work OK
takayoshi3 12/5/2012 | 3:34:05 AM
re: Fixed/Mobile Handover Vexes Carriers Thank you for the info. So, if I understand correctly based on 3GPP 43.318, it's *not* SIP based signaling. So when we say "non-UMA dual-mode phone" that means SIP based VoIP phone?
lrmobile_CLH 12/5/2012 | 3:34:03 AM
re: Fixed/Mobile Handover Vexes Carriers Please go to www.umatoday.com to find out about UMA.
takayoshi3 12/5/2012 | 3:33:59 AM
re: Fixed/Mobile Handover Vexes Carriers Thank you CLH for the pointer.

I think the term "UMA" in general is an abused term. 3GPP 43.318 (general access to A/Gb i/f) defines a set of protocols (sec.6.1 fig.4, for example), which are traditional 3GPP signaling and not SIP.

However, the term "UMA" itself doesn't imply any signaling protocol that it does or doesn't support. For me, when I hear "Unlicensed Mobile Access," it simply means an access technology using the unlicensed radio spectrum. Nothing more. It doesn't imply any signaling protocol that's being used with it.

Am I wrong???
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