Novel 5G architecture based on virtual networks
5G promises to usher in a new era of the all-connected, where anyone or anything that can benefit from a mobile connection will have one. As well as the enormous impact that it will have on our daily lives and businesses, 5G will also represent an opportunity to create an agile network that can adapt to the different needs of specific vertical industries such as energy, transportation and education as well as the economy. For example, some organisations may require more capacity, increased security and reliability, or a faster response time. The requirements for implementation of 5G technology cannot be satisfied by simply introducing new radio access technology; instead, a redesign of the whole network architecture is needed. Within the EU-funded project 5G NORMA, leading players in the mobile ecosystem worked to underpin Europe’s leadership position in 5G. The key objective was to develop a conceptually novel, adaptive and future‐proof 5G mobile network architecture. This architecture should allow adaption of the network to a wide range of service-specific requirements, resulting in novel service‐aware and context‐aware end‐to‐end function chaining. Customised networks 5G NORMA set out to meet the diverse requirements expected of next-generation mobile services through a flexible end-to-end architecture that takes into consideration both radio access network (RAN) and core network aspects. The first step towards this flexible architecture was the decomposition of network functions. This implies that some network functionalities consolidated in the RAN will move from the physical to the virtual world. “The proposed architecture allows the creation of dedicated virtual networks to be created on top of a common shared physical infrastructure. These virtual networks are then customised to meet the specific needs of applications, services, devices, customers or operators,” points out project coordinator Peter Rost. The flexible allocation of network functions provides an increased level of deployment flexibility, because instead of introducing diverse parameterisations of a common virtual network function (VNF), different VNFs can be allocated to different services. “A major aspect of the flexible architecture proposed by 5G NORMA was the ability to configure different functions or function blocks - both in terms of operation and physical location – and allocate them to different network slices,” notes Rost. In total, the project team developed 25 access and core network function blocks. Network slices’ management 5G NORMA’s network slicing solution – the partitioning of network architecture into virtual elements – capitalises on the capabilities of software-defined networking in addition to the VNF. Each network slice is controlled by a dedicated software-defined mobile network controller (SDMN-C), whereas the shared part is controlled by the SDMN-C coordinator that spans multiple slices. An SDMN orchestrator is used to manage slices throughout their life cycle. The project team also designed interfaces between the different modules and developed several methods to characterise the interaction amongst the different system components. The adaptability of the architecture is further strengthened by multi-tenancy and multi-service concepts. Multi-tenancy refers to the ability to serve multiple service providers from a shared infrastructure. Multi-service is the provision of a mix of services with varying quality-of-service requirements, in terms of throughput and reliability from a single network platform. “Within 5G NORMA, the consortium endeavoured to ensure economic sustainability of the network operation and open opportunities for new players, while leveraging a future-proof architecture in a cost- and energy-effective way,” Rost sums up. Given that service provider revenues stem primarily from post-paid mobile phone consumers, end-to-end network slicing should enable service providers to create new business opportunities with vertical sector customers.
Keywords
5G NORMA, 5G, virtual network, network architecture, flexible architecture, network slicing, mobile services, virtual network function
