The world today has become more connected than ever before thanks to globalization and the need to stay online all the time.

“Hey! Do you have a Netflix subscription?” Isn’t it very common to hear these words today? A leading report has revealed that around 20.8 billion devices will become connected to the Internet by 2020. Therefore, there is an increasing demand for a telecom network that is fast, robust, and can match the capabilities of other components in the ecosystem. This is where 5G network will play a major role. Not only will it provide faster access, but also provide enhanced capabilities like zero buffer video streaming that will become instrumental to the Internet of Things (IoT), artificial intelligence (AI) technologies, virtual reality applications, machine learning (ML), and so on. To be ready for 5G, there is an imminent need to shift the focus towards software-defined infrastructure that will serve as the foundation for future digital and other cloud-native services.

To be ready for 5G, there is an imminent need to shift the focus to software-defined infrastructure.

With Digital transformation becoming all about customer experiences and business model agility, 5G is expected to act as a true accelerator of change. So far, each generation of network technologies have broken existing barriers of supported speed and functionalities. 1G brought to us the very first cell phones, 2G let us exchange text messages for the first time, 3G brought us online, and 4G delivered the speed and capabilities that serve as the foundation of our digital lives. As the number of endpoints keep increasing, 4G is expected to fast reach its limitations, both in terms of speed and volume. 5G architecture is being seen as the alternative and solution to the limitations of existing telecom networks. For this, operators must embrace network slicing to cater to faster network demands, facilitate network automation, and allow network infrastructure simplification. This will allow software-defined networking (SDN) to truly act as the foundation for 5G.

What is Network Slicing?

Network slicing allows the creation of multiple virtual networks from a single physical network using the attributes of two closely associated network virtualization technologies such as Network Functions Virtualization (NFV) and software-defined networking (SDN), that are moving modern networks toward software-based automation.

The benefits of network slicing include better personalization through configurable services for specific customer use cases, driving more network automation, and network simplification. This in turn, is also expected to drive revenues through faster and newer services, and positively affect cost management as well. Customers, in the end, will get a faster, efficient, and reliable network to achieve their digital transformation objectives.

1. Role of SDN in Network Slicing for 5G

   5G claims to be truly Software Defined in terms of its core functions and end-to-end thereby adhering to bring advances to the telecom network where NFV architecture forms the base. The benefits of network slicing can be applied to today's networks including fixed networks and 4G mobile networks by providing configurable services based on customer need. 5G provides the unique ability to realize the vision of a truly converged next-generation mobile network infrastructure. It can enhance data transfer speeds, network capacity and reliability, and mobility while reducing latency. Understanding impact of 5G architecture on datacenter is very important as it can include expulsion of a lot of storage, computer, and network hardware from a typical data center in its current state.

   Typical functions improved by 5G capabilities are:
   1. Management and Orchestration of SDN/NFV Services

      This includes service coordination and instantiation through orchestration software that must communicate with the underlying NFV platform creating the virtual instance of a service on the platform followed by Service chaining for cloning and scaling of service to find and manage sufficient resources and finally Service monitoring for platform monitoring and management.

   2. Implementation of Network Slicing

      Network slicing is used to partition the core network into multiple virtual networks that can support different Radio Access Networks (RANs). Each virtual network comprises of a set of logical network functions isolated from each other. They are configured with their own network architecture, mechanism and network provisioning, providing independent orchestration and management. Slicing the network provides a unique set of optimized resources and network topology based on customer needs.

      1. SDN-Based 5G Architecture and Components

         Network slicing can introduce greater flexibility by partitioning network architecture to virtual elements. A major component of wireless telecommunications that connects individual devices to other parts of a network through radio connections, is 5G Radio Access Network (RAN). Each virtual element can support a different RAN along with different service types running across them. Each virtual network slice will be made of independent sets of logical network functions. It will also be virtualized based on SDN/NFV infrastructure which divides the user plane from the control plane into separate elements. User data messages can then be exchanged by the RAN controller through one of the SDN switches, and a second set through a control-based interface.

         

         Figure: Illustration of the software-defined 5G radio access and core networks

         Source: [Research Journal] https://www.hindawi.com/journals/wcmc/2018/6923867/

         In order to provide flexibility and scalability, SDN/NFV infrastructure provides orchestration of the resources revolutionizing the world of wireless communication.

   3. Allocation of Wireless Resources

      The resource allocation consists of a single base station connected to many receivers. Data for each receiver is maintained in a separate buffer. The goal is to allocate the network capacity fairly among users in accordance with their needs.

   4. Monitoring of Network Components

      To monitor a 5G network, operators can deploy physical and software agents in multiple strategic locations. The NFV infrastructure platform is monitored at edge locations and the orchestration is performed using similar tools that are used to deploy and manage the virtual network.

Security Challenges: There are security challenges that come along because of their open, flexible, and programmable nature. Also, the RAN side of 5G devices might pose the threat of Distributed Denial of Service (DDoS). Network slicing capabilities would demand unique security capabilities based on user needs. For example, the management interfaces in SDN could be used to attack the SDN controller or the management system, bringing the entire system down.

Tackling Security Challenges

To tackle security threats to 5G devices, there are four security mechanisms 5G networks need to meet:

• Cross-layer security: It refers to the coordination of different security methods for each security layer using a unified framework.
• End-to-end security: It will secure the communication paths between the user and the core network. It is challenging because of the distributed nature of 5G networks.
• Cross-domain security: It is a mandated need to fulfil vertical specific use cases. This requires cooperation between different domains in the 5G system for the enactment of integrated cross-domain security solutions.
• Security-by-design: Security must be built into the design during the development phase. As the network evolves, it should be able to adapt to changing environmental factors.

Business Impact of Software-defined Mobile Networks: New open-control interfaces and software-defined control will significantly reduce time and cost to reconfigure and optimize RANs. Upon implementation its will provide CAPEX benefits. In addition, 5G will also provide OPEX benefits through the more efficient use of radio spectrum, energy resources, and network infrastructure in the long run. Content providers and mobile network operators will be benefited by Over-the-Top (OTT) services tuned for RANs by network slicing and RAN sharing, while the end-user will experience smoother and faster network performance.

5G Popular Use Cases Across Verticals: A major chunk of consumer-related use cases will now become a reality with 5G. Market research shows that there will be 50 billion connected IoT devices by 2022. Drones, driverless cars, smart cities, and transportation can leverage the low latency of 5G networks and communicate faster, making real time insights in all walks of life a reality.

These networks have the potential to disrupt business models by enabling a range of new services and demanding high security levels across different industry verticals. In the healthcare field, 5G capabilities will facilitate faster transfer of large patient files, remote surgeries, and monitoring via IoT devices among other advances. Applications built on technologies such as Augmented Reality, virtual reality, AI, and IoT will benefit from the implementation of 5G.

5G networks are expected to be at least 100 times faster than 4G networks and cut latency to less than one-thousandth of a second. It will explore entirely new regions of the radio spectrum. SDN, NFV, and network slicing on 5G networks are poised to deliver benefits rolling out profits for related industries. Every upgrade has also been accompanied by concerns of compatibility with existing infrastructure, and 5G is no exception. Due to the lack of immediate architectural support for 5G networks, consumers will continue to experience 4G networks working in parallel with new-generation networks.

With the accelerating hype around 5G, there is no doubt that 5G holds a promising future as these networks will completely revolutionize how we use our phones and the Internet. But it will still be a couple of years before 5G reaches its full potential. Looking ahead, even as 5G rolls out, the buzz around 6G is starting up. Though 6G network technologies are still in their research and development phase, the promises of higher connectivity speeds, ultra-dense cell networks, and millimeter waves for user access would remain crucial in an industry where speed is everything.