Deutsche Telekom decides to go for circuit-switch fallback and eventually IMS to deliver voice services on its LTE network

Michelle Donegan

February 16, 2011

2 Min Read
MWC 2011: Deutsche Telekom Ditches VoLGA

BARCELONA -- Mobile World Congress 2011 -- Deutsche Telekom AG (NYSE: DT) has abandoned its pursuit of an alternative technology initiative for delivering voice services over LTE networks, called VoLGA (voice over LTE via generic access).

The German operator was the biggest supporter of the circuit-switch-over-packet technology, which is intended to be used as an interim measure to deliver voice services over LTE networks before the full implementation of IP Multimedia Subsystem (IMS)-based voice services.

But in an interview with Light Reading Mobile, Deutsche Telekom CTO Olivier Baujard said that there was not enough industry support for VoLGA.

"We have not created with VoLGA the traction we wanted or hoped," said Baujard. "We will implement the IMS-based solution, with CSFB [circuit-switch fallback]."

Instead of VoLGA, Deutsche Telekom will rely on its 3G networks to deliver voice services in the initial phase of its LTE offering, which is what's known as "circuit-switch fallback," before it will deploy IMS-based LTE voice services. But the operator does not see the need for LTE voice services before 2012 or 2013, according to Baujard.

When LR Mobile told the GSM Association (GSMA) director of technology Dan Warren about the comments made by the CTO of Deutsche Telekom, he said, "I could kiss you!"

That's probably because the emergence of VoLGA as an alternative technology to CSFB or potentially IMS-based voice caused a rift in the industry and sparked off worries of fragmentation among mobile operators. The development led the GSMA to spearhead an industry initiative to gather support for IMS-based voice over LTE, called VoLTE. (See Operators Rally Round IMS for LTE Voice, T-Mobile: Voice Discord Threatens LTE, New Specs Deepen LTE Voice Dilemma and Voice Over LTE & the 'IMS Gap'.)

Deutsche Telekom has long been a lone, yet significant, supporter of VoLGA. But it seems the German giant's size alone was not enough to move VoLGA from a preferred solution to a widely adopted industry standard. The operator's decision not to deploy the technology will be a blow to the Voice over LTE via Generic Access (VoLGA) Forum . Without Deutsche Telekom's support, it is unlikely the technology will be deployed by any other operator. (See Ericsson Quits Voice-Over-LTE Forum.)

— Michelle Donegan, European Editor, Light Reading Mobile

About the Author(s)

Michelle Donegan

Michelle Donegan is an independent technology writer who has covered the communications industry for the last 20 years on both sides of the Pond. Her career began in Chicago in 1993 when Telephony magazine launched an international title, aptly named Global Telephony. Since then, she has upped sticks (as they say) to the UK and has written for various publications including Communications Week International, Total Telecom and, most recently, Light Reading.  

Subscribe and receive the latest news from the industry.
Join 62,000+ members. Yes it's completely free.

You May Also Like