Circuit Switched fallback to protect network investments

Despite the growing momentum behind LTE deployments, one of the greatest concerns for established network operators is the legacy of their mature voice networks and their role in the all-IP future. This week, Chinese vendor Huawei trumpeted circuit switched fallback as an opportunity to leverage these legacy networks.

The Chinese manufacturer said Thursday that it has successfully completed a circuit switched (CS) fallback voice call, in a lab environment in Shanghai, demonstrating that operators using Evolved Packet Core to provide pure data services will still be able to leverage their existing 2G network to provide voice services.

Early LTE deployments have not addressed the need for voice services over the new technology. Tommy Ljunggren, SVP and head of system development, mobility services at LTE pioneer TeliaSonera, and one of the Nordic carrier’s leading speakers on its LTE deployment, said that his firm’s 4G launch was easier because the firm, “Focused on data only and not complicated it with voice and voice integration with legacy systems and so on.”

According to the standard solution defined by the 3GPP, CS fallback is considered the preferred solution for the early stages of LTE or EPC network deployment as it allows operators to make full use of their existing networks to protect investments.

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  1. Avatar hazim ahmadi 14/01/2011 @ 10:08 am

    It is not important whether vendor can do it in lab. The most important thing for operators is how vendor can fully support in implementation and commercialization.

  2. Avatar Steve Shaw 17/01/2011 @ 11:17 am

    Reverting to CS Fallback highlights some of the problems operators face in launching LTE networks. Voice is still the primary revenue generating application, often accounting for 70% or more of an operator’s revenue. However, technologies like CS Fallback, which force the phone to drop the existing LTE connection and ‘fall back’ to GSM technology, to make or receive a call, are a step backwards for subscribers and network operators alike.

    An alternative solution is VoLGA – VoLGA turns the operator’s existing cellular voice service into a mobile VoIP service over LTE. It is an elegant approach for bringing voice revenues to LTE, providing a smooth migration to longer term SIP-based solutions.

  3. Avatar Attila Sipos 17/01/2011 @ 4:47 pm

    Sooner or later mobil operators should go to use the VoIP (IMS)sollutin above thear broad band mobile access (LTE) like fix operators did it.

  4. Avatar gilad 20/01/2011 @ 12:03 pm

    How about Edge+ as fallback for Data Services over LTE .

  5. Avatar Brent 27/01/2011 @ 1:22 pm

    I would be interested to know how common CSFB will be in the industry. It looks like most carriers are waiting for dual-radio Rx devices to reduce the network complexities.


  6. Avatar Peter Chen 08/03/2011 @ 6:26 pm

    Is there any company making module which can do LTE data and voice ?

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