In the recently concluded LTE Asia event (18-19 September) in Singapore, one of the key discussion topics was how to improve network capacity to meet ever growing demand for mobile data usage. The discussions made it quite apparent that smartphones and tablets were putting a lot of pressure on operators to quickly increase their network capacity in high traffic zones and during peak hours.
The two much talked about technologies to overcome the capacity challenges were – Wi-Fi offloading and small cells. Wi-Fi being the older of the two attracts immediate attention. Operators across the globe are now increasingly deploying their own Wi-Fi hotspots or leveraging existing infrastructure of Wi-Fi/fixed broadband service providers to offload their data traffic. With the advancement of Wi-Fi technology, their offloading strategy is slowly evolving. Now, they are not only extensively using Wi-Fi offloading to reduce load on their network but also integrating it with their cellular (macro and small cell) networks for delivering better user experience and better traffic management. “Managed Wi-Fi improves coverage, capacity, and QoE offsetting backhaul costs. However, despite Wi-Fi ubiquity, it lacks control plane integration, seamless session control, telephony service integration, security, and regulatory compliance,” said John DePietro, Director of Strategy and Business Development, Benu Networks. The other challenges are delivering end-to-end QoS as that of licensed spectrum, and intelligent network selection and routing to selectively offload traffic.
As compared to Wi-Fi offloading, small cell is a fairly new technology. Small cell offers benefits such as control over the spectrum, traffic management, they are fully integrated with macro cells/mobile network, and the handover is seamless. Operators can manage traffic and capacity as they do for macro cells. However, small cells have their own set of challenges like high deployment cost and frequency interference (often both macro and small cell use the same spectrum channels).The interference can offset the capacity gains. Also, because they are fairly new solutions, operators are still exploring their backhaul challenges, deployment models, and tools to manage interference.
The delegates I interacted with at LTE Asia suggested that the potential of both the technologies could be best realized as complementary technologies rather than one replacing the other. Both technologies have different deployment scenarios and different advantages. While Wi-Fi access points are mostly deployed in indoor locations, small cells are deployed in outdoor locations in dense traffic zones that can cover both indoor and outdoor users in smaller areas. Because of the ubiquity of Wi-Fi infrastructure, Wi-Fi offloading is an immediate solution to relive network load and improve capacity. However, in the longer run, operators need to use both small cell and Wi-Fi to overcome the capacity and coverage challenges. In fact, unlike 3G, small cells are part of network planning in LTE deployment, rather than an afterthought for improving in-door coverage. It is very likely that with the proliferation of LTE networks, small cells and Wi-Fi will be provided more as an integrated solution.
Whatever be the deployment case, the experts at the event suggested that operators need to address the following challenges to deliver a seamless connectivity and throughput to their users.
- How to implement Wi-Fi Alliance PassPoint program, Hotspot 2.0, and SIM-based authentication to improve Wi-Fi offload experience?
- How to offer seamless handover between Wi-Fi and small cells/mobile network?
- How to build device capability to automatically choose the best available access point?
- How to integrate QoS/performance on Wi-Fi networks?
- How to implement secure, scalable, small/macro cell backhaul, and aggregation solutions?
- How to reduce cell interference in small cell networks?
For further insights on addressing these and other challenges please read: