The prospect of new revenue streams from Internet of Things (IoT) is enticing for carriers. But there’s an elephant in the room.
The centralized cellular network architecture in use today across the globe was designed to handle millions of smartphones, but not billions of IoT endpoints using a wide variety of network protocols. It is likely not up to the job of handling the looming mobile network traffic overload problem expected to arise from the projected massive influx of IoT devices.
The IoT Crunch
Billions of IoT devices are predicted to come on stream within the next few years: Gartner expects 6.4 billion connected “things” to be in use worldwide this year, up 30 percent from 2015. The analyst firm further expects the number to reach 20.8 billion by 2020.
IoT will demand much more of our wireless networks, in terms of load as well as flexibility. The embedded sensors already keeping tabs on electricity meters or tracking shipping containers are just the tip of the iceberg. IoT will enable new levels of wireless connectivity in a huge range of things by bringing devices, people and analytics platforms together. Combining sensor and aggregated data with other available facts and figures will spark new services, applications and opportunities.
With the influx of IoT, I believe we will see an increasingly heterogeneous communication landscape. Over the past decade, mobile networks have assumed that all devices are on the same evolutionary path – from 2G to 3G to LTE – all running on protocols defined by 3GPP. In the IoT world, however, no single protocol will prevail. We are already seeing several parallel efforts with specialised and optimised non-3GPP protocols, LoRa and Sigfox representing just two examples.
High bandwidth, low latency IoT applications such as live video streaming from a remote camera will require LTE, whilst LoRa and Sigfox are better suited for lower bandwidth applications – such as smart water meters or other sensors requiring infrequent data transport – where low power consumption and low costs are the main criteria. If operators want to play a central role in IoT, they will need to open up to the new heterogeneous world of IoT and embrace true openness.
Considering the massive influx of devices to existing networks, I further believe that we are at risk of overloading the core networks. In order to avoid cellular network meltdown and to help carriers benefit fully from the IoT boom we need to reduce the pressure on the central core. And to do this, we need to rethink how mobile networks are designed. I’m not suggesting a complete overhaul, which would be rather unrealistic, but an evolution: one in which carriers take advantage of Mobile Edge Computing to enhance and prepare their existing LTE networks for the tidal wave of IoT.
To provide more insight into the problem, let’s look at the current mobile network architecture. Today’s LTE networks are based on a star topology with a centralised Evolved Packet Core (EPC) for handling authentication, signalling and network traffic. The average base station typically handles signalling for up to 1,000 to 1,500 devices. As future IoT applications emerge, a base station might have to manage hundreds of thousands of sensors and actuators, each one sending signals and transmitting data.
Besides the radio congestion issues, which could be addressed with smaller cells and radio planning, this surge of devices will likely put significant strain on backhaul traffic, which will become a critical bottleneck as devices communicate back to centralised core networks. Handling authentication, signalling and traffic for billions of devices will overload the centralised EPC, resulting in degradation of service quality for smartphones and triggering large investment requirements for carriers struggling to handle the load.
Lessons from the Internet
Fortunately, the Internet offers some interesting lessons for the carrier community. It is a perfect example of a decentralised mesh combined with a star-of-stars topology, which is why the growth to billions of endpoints was handled so elegantly. By applying this model to the mobile telecoms world, we can prevent the central core networks from drowning in the flood of data and signals emanating from billions of IoT devices.
Telcos have already started out on their journey to bring more Internet technology to the mobile networks with new initiatives like Network Functions Virtualization (NFV) and Software Defined Networks (SDN) igniting network architecture redesign. With NFV and SDN, carriers no longer need to use expensive dedicated hardware for separate service functions, but can virtualize services using software running on standard computing hardware. As a result, cellular networks will become more flexible and cost-effective.
Mobile Edge Computing as a Solution
However, a complete overhaul of existing cellular networks will be very expensive and will probably take many years to complete. Therefore, I expect to see the first significant deployments of NFV/SDN at the edge of the mobile network. Mobile Edge Computing (MEC) is a new concept, which provides an IT service environment and cloud-computing capabilities at the edge of the network, close to or even right at the base station. Based on virtualization, MEC promotes decentralised core networks providing connectivity and computing at the edge, running applications and even the EPC closer to the devices.
With a decentralized EPC running at the edge of the network, some of the load from all these devices can be sectioned off from the central network and local traffic can stay local, preventing central EPC overload and reducing backhaul traffic at the same time. Applications, such as sensors and actuators for factory automation for example, will reap the benefits of reduced latency and much faster device-to-device communication as a result. I believe offloading signalling to the edge and keeping local traffic local will become key to preventing central network and backhaul overload.
Mobile Edge Computing will have an important role to play in the evolution of core networks for the IoT era. By taking the existing core network architecture to the edge of the network, and opening up the cellular network to non-3GPP protocols, carriers will be able to provide a resilient, cost-effective wireless infrastructure for the foreseeable future.
Carsten Brinkschulte is the CEO of Core Network Dynamics (CND). CDN is a European mobile technology start-up that developed OpenEPC, a complete mobile network infrastructure in software that can run on commodity hardware as small as a Raspberry Pi.
Filed Under: Infrastructure, IoT • IIoT • internet of things • Industry 4.0