With the potential for exponentially more capacity, lower latency, increased reliability and availability, 5G holds the promise of ubiquitous connectivity, converging both fixed and wireless access technologies as well as licensed and unlicensed spectrum. With these lofty goals, the vision of a fully mobile and connected society offering services and capabilities far beyond today’s mobile networks may become a reality.
In short, 5G is expected to offer the following capabilities to everyone whether human or machine:
- Service available anywhere at anytime
- Services delivered with consistent experience
- Services accessible on multiple devices and access technologies
- Services supporting multiple interaction types
- Services delivered seamlessly and transparently across access technologies
- Services delivered in a contextual and personalized manner
- Services that are enabled by secure and trusted communications
- Services supported by a highly reliable and resilient network
- Services delivered in a responsive and real-time manner
Combine these features with networks that are more spectrally efficient than their predecessors, support substantially more users and higher device connection densities, offer higher data rates, lower latency and prolonged battery life of connected devices and you are looking at the holy grail of networks.
Of course, a lot of things – and I mean A LOT of things – have to happen in the near term, with an agreement on a standard being a priority. With multiple organizations throwing their hat in the ring, there is no lack of enthusiasm for developing a 5G standard. In the end, it is expected that the ITU, in partnership and cooperation with 3GPP, NGMN, and GSM among others, will take the lead in standards development for 5G, building on its IMT family, which includes IMT-2000 (3G), IMT-Advanced (4G) and the current work in progress, IMT-2020 – which will serve as the foundation for 5G.
5G’s Unique Value Proposition – Anything-as-a-Service
With each generation of mobile networks the service focus has shifted – from voice to data to mobile broadband. Although the mobile broadband usage scenario will continue to play a key role in 5G, a much wider set of diverse usage scenarios are anticipated. With performance parameters being defined, such as virtually no latency combined with broadband speeds of more than 1Gbit/s, the services offered with 5G will move beyond audio and data towards visual, tactile and cognitive, creating an environment that allows for Anything-as-a-Service.
However, while variety is the spice of life, 5G use cases will demand very diverse and sometimes extreme requirements. In addition, with several diverse use cases anticipated to be active concurrently in the same operator network, the need for a high degree of flexibility and scalability will be critical.
Per the ITU’s IMT-2020 Focus Group, three major uses cases have been defined:
Each of these use cases has substantially diverse requirements. For instance, sensors and many IoT applications typically do not require massive bandwidth or mobility, but they do need low energy consumption and long battery life. On the other hand mission-critical services, such as public safety, require ultra-high reliability, high-security, mobility and ultra-low latency.
So how do they support all of these variations?
5G: A Showcase for Virtualization
5G is expected to fully leverage the advantages and capabilities of open-source, software-driven networks. With a large portion of the network elements expected to be virtualized, the 5G network will be able to both automatically and dynamically adapt radio access and core network resources to support the wide-ranging requirements of the various use cases. Additionally, by understanding how the connectivity is being used, the network will be able to provision network resources as needed, allowing it to run more efficiently and hence more cost effectively.
A key element to making all this happen is the ability of 5G to adapt network resources in both the user plane and the control plane to meet the performance levels of each service and device. By “slicing” the single physical network into multiple, virtual, end-to-end networks, an operator can software define the necessary performance criteria – such as speed, security, coverage area, etc. to match the requirements required by a service using the slice.
Each slice will be composed of the necessary logical network functions that support the service requirements of the particular use case or even class of service. While some slices will have extensive functionality, others may be very limited. In this scenario, a device will be directed to the appropriate network slice that fulfills the operator and user needs based on either the device type or subscription.
This level of flexibility opens up tremendous opportunity for operators to not only expand existing services, but also introduce new services/subscriptions, etc. And there are many technologies expected to be expanded and/or introduced into 5G, such as mobile edge computing (MEC), massive MIMO, millimeter wave (mmWave) and device-to-device (D2D) communications, to name only a few.
The concept of network slicing should help operators deliver on the many promises of 5G and provide that holy grail of networks. But virtualization isn’t the only technology that will be fully exploited in 5G networks: D2D communications, MEC, mmWave, Massive MIMO, and contextual awareness (at the device, network and user levels) are only a few that will have significant impact on how the world will become fully mobile and connected.
For additional information on network slicing, the NGMN Alliance has recently issued a document defining the concept of network slicing which consists of three layers: Service Instance Layer; Network Slice Instance Layer, and Resource Layer.
The Service Instance Layer represents the services which are to be supported, with each service represented by a service instance. A network slice instance provides the network characteristics, which are required by a service instance and may be shared among multiple service instances. While the resource layer comprises the physical and logical resources. The network slice instance may have none, one or more sub-network instances, which may be shared by another network slice instance. A sub-network instance comprises of a set of network functions and the resources for these network functions.