Digital Transformation is reshaping almost every industry, heralding unprecedented opportunities and challenges for each vertical. Digital continues to shape the new marketplace as brick-and-mortar gives way to e-commerce, structured industries yield to uberization and content goes over the top. Disrupt or be disrupted, is the mantra of this Digital marketplace. And 5G is about hypercharge this Digital Transformation.
5G will be the transformational tipping point that will deliver unprecedented productivity gains, redefine competitive advantages and accelerate global market reach reshaping every industry vertical (including agriculture, automotive, healthcare, manufacturing, energy, transport, gaming, media & entertainment etc.). Businesses will reexamine their P&L with a 5G lens. Network will become the differentiator that will redefine business processes, foster business innovation and pioneer new production, distribution and consumption models. Those who prepare well for 5G have much to gain and will be the disruptors. Others run the risk of being disrupted.
5G Use Cases
To meet the diverse Digital requirements of different industry verticals, 5G use-cases are broadly classified into three buckets: eMBB (Enhanced Mobile Broadband), MIoT (Massive IoT) and uRLLC (Ultra-Reliable Low Latency Communication). Each with different set of requirements for the network:
Following three network KPIs (Key Performance Indicators) succinctly capture the use cases’ diverging requirements:
5G must solve delivering one network that can meet all these diverging requirements
5 Laws shaping 5G
5G has to solve for delivering one network that meets all the aforementioned diverging requirements. Following are the five laws that are fundamentally shaping the 5G network:
5G Infrastructure: A Distributed Telco Cloud
Networks are inherently hierarchical and distributed in nature. 5G Infrastructure will be a Distributed Telco Cloud built by leveraging merchant silicon, COTS hardware and Cloud OS. Network Functions (NFs) themselves will be dis-aggregated, virtualized, will be truly cloud native and deployed as workloads on the Telco Cloud. Decoupling NFs from the underlying infrastructure enables them to be orchestrated and dynamically placed at different locations of the Telco Cloud, thereby, enabling creation of logically independent network slices on a shared infrastructure. This in turn enables CSPs to create multiple logical network slices that best meet the varying requirements of bandwidth, connection density, latency, elasticity and cost. The distributed infrastructure will further enable CSPs to host NFs as well as 3rd party applications from different industry vertical in a way that best meet both the technical and business requirements. Edge Cloud in particular will bring compute and storage capabilities closer to the end device/thing (UE) and will be critical for meeting the requirements of ultra-low latency applications and for efficiently managing ultra-high bandwidth applications.
A three tier Distributed Telco Cloud Architecture can vary depending on CSP’s existing infrastructure, geographic footprint and end application requirements. Distributed Telco Cloud will enable CSPs to achieve the Cloud-like economies of scale and simultaneously balance stringent requirements like ultra-low latency. The Distributed Telco Cloud operating model will be: “Centralize what you can. Distribute only what you must”.
5G is changing the network’s anatomy to enable CSPs to offer wide range of Digital Services. Historically, appliance centric networks were engineered to meet the requirements of limited set of services like voice, messaging, data and video. These networks however have proven to be inflexible to meet the diverse and varying requirements of Digital Services. As we move past the era of limited killer-apps to an era of diverse Digital Services, 5G is holistically redefining the network end-to-end, including both the Access and the Core Network.
5G AN: Access Network
To meet the diverging needs of eMBB, MIoT and uRLLC use cases, 5G AN (Access Network) will be dis-aggregated and virtualized. To meet the ultra-high throughput and ultra-low latency requirements, 5G NR (New Radio) will operate in diverse spectrum bands spanning across low, mid and high spectrum bands. To deliver average 1Gbps data rates and to solve for the cell edge problem, 5G AN will employ advanced phased antenna array technologies including MU-MIMO and Beamforming.
In the world of Cloud, best-of-breed has already won. With 5G, CSPs now have the opportunity to dis-aggregate and virtualize the RAN (vRAN) and pave the way for best-of-breed 5G AN solution. Leveraging the vibrant eco-system of vBBU, RRH, AAS, SON and COTS white-box suppliers, CSPs can drive margin stacking out of their supply chain and break the large OEM’s vendor lock-in on their RAN. Benefits of vRAN go well beyond the equipment cost, as it greatly simplifies/reduces the RAN site deployment cost and significantly reduces OpEx by driving energy and cooling costs down at the Base Station (BS) sites. vRAN further provides added benefits of energy management, dynamic network scaling and high availability, all of which will be key requirements for 5G.
5G splits the gNodeB architecture into Centralized Unit (CU), Distributed Unit (DU) and the Radio Unit (RU). The architecture offers various options for splitting the gNB stack across real-time and non-real time functions of the RAN. The split choice would depend on a number of factors including underlying transport network, spectrum channel bandwidth, fronthaul bandwidth requirements, connection density and latency tolerance. Above all, vRAN will enable end-to-end network slicing in 5G network.
5G NR (New Radio) will enable operators to tap into mmWave spectrum bands, above 24GHz, to create fat OTA (over the air) pipes. Ample spectrum available in these mmWave bands, facilitate CSPs to create network that will deliver ultra-high throughput and ultra-low latency. However, use of these higher spectrum bands have their own set of challenges including high propagation loss, required line-of-sight (LoS) and high susceptibility to signal blocking. Challenges span across both indoor and outdoor environments as typically these signals cannot even penetrate walls and can easily be blocked by foliage or even moving vehicles in urban environment. Deploying in mmWave bands necessitates sites to be in close proximity. Poles and other street furniture provide ideal deployment sites as these bands would be best suited for dense urban population areas that need massive capacity boost. Advanced antenna techniques including beamforming and beam tracking will be employed for mobilizing mmWave in non-line-of-sight environments. In addition to mmWave, CSPs will also employ diverse spectrum assets below 6GHz and even below 1GHz to provide ubiquitous 5G coverage. Balancing traffic demand against deployment costs will govern how CSPs acquire and deploy their spectrum assets to create adequate coverage and capacity for their 5G network nationwide.
5GC: Core Network
5G Core will be truly cloud-native, deployed on a Distributed Telco Cloud infrastructure, delivering unprecedented Service Agility. SDN and NFV are the foundational pillars of the 5G Core Network. For the very first time, 3GPP has specified Service Based Architecture for 5G Core, in addition to the traditional Reference Point Architecture (used in 2G, 3G, 4G and now 5G). Service Based Architecture holds the key to rapidly enabling wide range of Digital Services with varying requirements from different industry verticals.
Existing mobile core networks have only one set of logical control functions and this in turn has artificially limited the service set that CSPs can offer to their customers. If a new service introduction required modifying an existing network function or introducing new network function(s), then CSPs had to undertake the complex task of integrating and retesting their entire core network end-to-end and would typically take anywhere from six to eighteen months – this will no longer works in the Digital Services era. This architectural rigidness has fundamentally inhibited CSPs to rapidly offer new services and efficiently seize market opportunities. In sharp contrast, web-scalers have demonstrated rapid service introduction and elastic scaling capabilities. Service Based Architecture brings that cloud agility to the 5G Core Network. Different Network Functions can be quickly composed and orchestrated into a new end-to-end service making it easier to add, modify or remove NFs from service chains and even quickly realize new service chains.
Just like microservices interact to create complex cloud applications, 5G Core will be composed of self-contained reusable software modules of network function services. This modularity enables dynamic composition of different network cores on a per slice basis, with varying capabilities, that best meet the end service requirements. Also like cloud application, 5G core network functions will mostly be stateless decoupling the compute and storage resources which in turn enables faster scale-out, flexible NF placement and new software enabled redundancy models for high availability and geo-redundancy. Minimizing state will be a key challenge for 5G NFs and key is to keep stateful services to a minimum.
Cloud native, Service Based 5G Core lends itself very well for Network Slicing by allowing reuse of network function services and even rapid network function customization, as needed, across slices. In addition to the traditional core network functions like authentication, session management and mobility management, 5G Core introduces new functions like Network Slice Selection Function (NSSF), NF Repository Function (NRF) and Network Exposure Function (NEF) to support cloud native Core and Network Slicing. NRF maintains NF repository enabling registration and discovery of could native NFs for cloud-like operations. NEF is like an API Gateway, allowing external users to define and enforce policies per their end application requirements. NEF is particularly important to enable Digital Services for diverse industry verticals and enable cloud like Self-Service/DIY operational models. NSSF enables Network Slicing by assisting selection of the right Network Slice instance, in a multi-sliced core, that best meet service specific requirements.
An important aspect of the cloud native 5G Core is the separation of Control and User Plane functions. Web-scalers have used similar architectures to efficiently scale their cloud applications with centralized control and distributed processing to efficiently scale sessions and transactions. Control and User Plane Separation (CUPS) in 5G Core will enable independent scaling and evolution of control plane and user plane functions. Architecturally this will enable networks to efficiently scale and respond to data tsunamis and/or signaling storms, as the case maybe. Furthermore, this will enable flexible deployment of user plane functions at regional or edge clouds to optimally meet the high throughput and low latency requirements of the end application.
5G Core will be Access agnostic. This will enable CSPs to deploy a converged core network which will integrate both 3GPP ANs (like 5G NR, 4G LTE) as well as non-3GPP Access Network (like WiFi).
Network of the Future will be dynamically sliced and differentially priced.
Network Slicing will enable CSPs to create different logical networks, on a shared Telco Cloud infrastructure, with varying capabilities that best meet the varying requirements of different applications. Throughput, latency, security, mobility requirements can all vary from application to application. Furthermore, economic models across eMBB, MIoT and uRLLC will greatly vary and in turn will put varying demands on the network.
To enable cloud-like On-Demand, Self-Service/DIY models for different industry verticals, Network Slicing will pave the way for CSPs to offer differentiated services at differential price points. CSP can offer network slices with varying throughput, latency, mobility, security etc. to the end user and can even offer varying levels of granular control for the slice.
Harnessing the power of Virtualized RAN (vRAN) and cloud native Core, 5G network can dynamically allocate resources and generate network topologies with the right set of NFs (Network Functions) that best meet the end service requirement. Resources can be dedicated or shared across slices. A slice itself can support one or many services.
In a nutshell, Network Slicing can be summed up as the network adapting itself in software to deliver optimal network topology capability and resources that best meet the end service requirements. To illustrate the adapting capabilities of a 5G network, let’s take three different use cases with three different service requirements:
Barring an unforeseen Greenfield operator, 5G will be rolled out in phases. 3GPP standardized Non-Standalone (NSA) mode in December 2017, and in June 2018 3GPP released the standards for Standalone mode (SA) as well.
Most of the 5G trials and early rollouts will be deployed in Non-Standalone mode leveraging 4G LTE Core and RAN for ubiquitous coverage and 5G NR selectively deployed to boost capacity and data rates. This provides the fastest path for CSPs to launch 5G commercial services. Non-Standalone mode is also currently being used by CSPs to study and characterize RF Propagation characteristics of mmWave spectrum band.
Eventually, to reap the full benefits of 5G, CSPs will migrate to Standalone mode. Enabling wide range of Digital Services will require CSPs to deploy 5G Core Network and automate end-to-end Network Slicing. Progressive CSPs have already initiated deploying their Telco Cloud, LTE vRAN and Virtualizing their 4G EPC. Further, they are also deploying CUPS in their 4G EPC, paving the way for 5G Network and simultaneously minimizing stranded investments.