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MAKING THE CASE FOR VoLTE Any assessment of the decision criteria to invest in VoLTE must also comprise ongoing OPEX savings for all network operations; as well as the need to increase capacity for other LTE services. One of the principal savings, long term, can come from consolidating mobile networks onto an IP architecture. Voice services in a 3G infrastructure are circuit switched while data services run on separate IP backbone meaning that a contemporary 3G operator has to manage two networks concurrently. By embracing VoLTE in an LTE deployment, voice, data and video services are all supported over IP. Whilst consolidating mobile networks is a complex migration and transformation, the economics mean that consolidating multiple technologies should remain an attractive long term goal for most operators. In South Korea and Japan we are seeing operators do just that, with aggressive 2G and 3G switch off plans. VoLTE is a key enabling technology in those strategic aims, as it provides the core voice infrastructure of those future network, ensuring both a protected consumer experience and longevity for the voice revenue stream. There are other benefits too, from VoLTE. The technology provides a dramatically shorter call set up time than fallback technologies, with VoLTE calls able to be established in as little as 0.25 seconds, compared to 5-10 seconds for calls falling back to the 3G circuit switched network. VoLTE also brings with it support for HD voice codecs in an interoperable way between devices across an operator's network. HD Voice is of itself of growing importance to the consumer experience. the moment. Overall voice revenues are declining or showing signs of peaking partly because of the popularity of device or OS-centric services such as Facetime, or internet-based services such as Skype, but in much larger part due to the effects of competition and regulatory intervention on termination rates. Making the case for investment in something to support voice is a hard thing to do. As long as "good enough" voice is supported, making upfront CAPEX investments in an IMS just on the cost- benefit analysis of providing voice is much more challenging to justify. There are other reasons too. There is a perception that the deployment of an IMS, which is required for the support of VoLTE, is extremely costly and complex to integrate in existing mobile networks. Allied to this are additional concerns around signalling load between policy, charging and application servers in the core network, device support being thin on the ground - especially in implementation of SR-VCC capability - and ensuring quality of service across the network. that we still have only a tiny number of operators who have deployed what is now a three year old standard for serving voice over IP in LTE networks. Why are we where we are? Certainly, sporadic or geographically patchy LTE coverage is one reason why we haven't seen a quicker drive to VoLTE. While LTE coverage remains concentrated on specific urban markets, a fallback solution makes more sense than VoLTE, which provides its principal benefits across areas of continuous or widespread LTE coverage. But operators surely do not plan to limit LTE to a few markets for any more than the near term, and certainly as more digital spectrum comes online in many markets we will see wider geographic coverage rolled out over the next 12-18 months. So while limited network rollout may be one short term explanation, it cannot explain the overall lack of strategic drive to VoLTE. Perhaps we must look for another reason. One place to look is that it takes a brave person to outline the case for more investment in voice technology at Acquiring new spectrum is a significant investment for mobile operators - certainly much more than an investment in an IMS. A VoLTE deployment can reduce or defer new spectrum purchases, easily justifying an IMS investment for VoLTE. A TMN EBOOK: VOLTE - MOVING FROM DELAY TO DEPLOY

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