To date, more than 300 mobile operators around the world have committed to LTE network investments to meet subscriber demand for more and more bandwidth. Operators must figure out how they can monetize these new networks while paving the way for their next-generation network rollouts beyond LTE. In this article, Radisys shares its thoughts on what’s driving this network transformation and what operators should be considering as they address deployment challenges and opportunities.
What are the factors behind operators’ drive to transform their networks?
One of the key drivers behind this transformation is the proliferation of mobile applications, particularly video, that are running on a plethora of smartphones and tablet devices. Today’s consumers want anywhere/anytime access to mobile broadband, and operators are responding with the roll-out of their LTE networks. Initially, LTE will enable operators to offer mobile broadband data plans with higher speeds and lower latency than 3G networks can deliver. However, the traffic growth is outpacing revenue growth by a significant margin—which is clearly not a sustainable business model for the operators. To address this gap, operators need to offer consumers additional services to differentiate their LTE offerings and grow revenues. This is where services such as Voice over LTE (VoLTE) and Rich Communications Services (RCS) come in.
What is the traction for Voice over LTE (VoLTE) and Rich Communications Services (RCS)?
We’ve seen a lot of activity to date this year for VoLTE and RCS trials and deployments and see 2013 as the year when VoLTE deployments take off. The world’s first VoLTE deployment from MetroPCS, launched in 2012, was based on Mavenir Systems’ IP Multimedia Subsystem (IMS) solution powered by our Media Resource Function (MRF).
Research firm Strategy Analytics has predicted that South Korea, Japan and the U.S. will lead the way with VoLTE deployments, and will be joined by a wave of mobile operators globally over the next 24 months.
Our own research shows that 18 percent of operators have already begun to deploy VoLTE and RCS, while an additional 37 percent are planning to do so over the next year. Operators are turning to these services to reverse the downward revenue trends in voice and messaging, which are still their primary sources of profit. Operators that bundle VoLTE and RCS with their LTE deployments are able to offer their subscribers more attractive service offerings than just LTE data plans, and hence are gaining market share.
How are IMS architectures being leveraged?
Both VoLTE and RCS are based on standards-based IMS services delivery architecture, so operators must consider an IMS deployment as part of their LTE network. The Media Resource Function processes the real-time audio and video media streams under the control of Call State Control Functions (CSCF) or Application Servers (AS) in the IMS. In addition to delivering revenue-generating VoLTE and RCS, operators that have deployed an IMS can also introduce additional service innovations as the signaling, billing and QoS control mechanisms are already in place. Adding a new service requires just a simple addition to the IMS Application Server.
This same theme of IMS reuse for multiple service offerings also extends to the MRF. Radisys’ MRF has been specifically designed to support a wide range of audio, video and speech applications. For example, an IMS powered by Radisys’ MRF supporting VoLTE and RCS today can also offer video conferencing or video ring-back services for revenue growth. This is due to the fact that the MRF already supports video transcoding and mixing so the addition of a video conferencing service is a relatively straight forward addition to the IMS Application Server layer only.
Another key point is that an MRF as part of the IMS architecture also supports the transcoding and transrating for multi-service compatibility. What this means is that operators can support backward compatibility with legacy 3G networks. For example, VoLTE uses high-definition audio quality codecs (AMR-WB) while 3G networks use AMR narrow band (AMR-NB). To maintain backward compatibility, the IMS uses the MRF to provide transcoding between VoLTE (AMR-WB) and 3G handsets (AMR-NB). When it comes to video, transrating is also important. In this instance, the MRF could be called upon to change the picture size, bitrate or frame-rate, depending on the endpoint capabilities or the available mobile access bandwidth that can fluctuate during a call. Adding an IMS architecture with a scalable and flexible MRF solution to an LTE network is an incremental investment with massive payout potential for operators.
What considerations are there for the shift from LTE to LTE-Advanced? What enhancements does LTE-Advanced bring to the network?
We’ve just talked about how operators are deploying LTE to meet the growing bandwidth demands on their networks, but while LTE is being rolled out, savvy operators are already planning their LTE-Advanced deployments. LTE-Advanced promises to deliver upward of 1Gbps peak downlink data rates to deliver true 4G speeds. In addition, LTE-Advanced enables enhanced cell edge performance, much improved radio interference mitigation and spectrum reuse via carrier aggregation like features. This is good news for subscribers and operators alike.
For subscribers, they’ll get access to real-time HD voice and video services and fewer dropped calls. Operators get increased network capacity and efficiency to keep pace with traffic demands along with monetized mobile broadband to support their revenue goals.
How does an LTE-Advanced deployment differ from LTE? What do operators need to know?
There are a number of techniques that are key for a successful LTE-Advanced deployment. Carrier aggregation enables operators to combine all available spectrum – 3G, LTE and LTE-Advanced – to deliver even more data throughput at one time. LTE-Advanced’s new MIMO (Multiple-Input Multiple-Output) techniques support up to eight transmit and receive antennas, hence 8x8 MIMO, up from 4x4, providing even more performance increases. Improved interference mitigation can be achieved through the implementation of Enhanced Inter-cell Interference Coordination (eICIC) techniques. Finally, operators can implement Self-Organizing Network (SON) features that go beyond auto configuration to help mitigate interference by providing effective coordination of RF resources and efficient algorithms for mobility and load balancing.
Operators should apply a phased approach to their LTE-Advanced deployment in order to maximize their network investment while realizing immediate capacity and efficiency gains.
What role do small cells play in an LTE-Advanced network?
Small cells play a critical role in the deployment of LTE-Advanced networks to deliver enhanced cell edge performance- another key technique. The deployment of a multi-layer network of macrocells and strategically placed small cells – a Heterogeneous Network or Het Net – further increases network capacity while providing spot coverage for better performance at the cell edge. No more dropped calls. Small cells benefit from the LTE-Advanced techniques such as carrier aggregation and improved interference mitigation to help deliver LTE-Advanced’s powerful combination of capacity and coverage.
The telecom cloud is a hot topic. Why is the Telco industry exploring opportunities for cloud technology?
No discussion of LTE networks is complete without talking about the emerging Telecom Cloud. Operators are keen to take advantage of the benefits of cloud technology that have been achieved in the Enterprise realm- namely economies of scale, cost effectiveness, scalability, lower CAPEX and OPEX. However, the Telco industry has more exacting requirements for five-nines availability, scalability and reliability.
Operators are looking to virtualization technology to obtain better utilization of their equipment, and thereby achieve cost savings. Software-defined Networking (SDN) is one of the methods that will help operators decouple their applications from the dedicated hardware. SDN helps operators automate their networks, allowing them to deploy services faster and with greater flexibility. It also provides independent scaling of the control plane and data plane by separating the two functions. Radisys’ approach first enables this separation within the same platform, lowering integration risk. Operators can separate the control plane to be outside the platform when ready, further reducing CAPEX and OPEX.
A series of in-depth webinars, hosted by expert members of the Radisys CTO office and Product Management teams will address the key challenges operators are facing and share real-world expertise for successful VoLTE, LTE-Advanced and Telecom Cloud deployments. Register here