5G Infrastructure Design

In this chapter, we will focus on the infrastructure design required to successfully implement the network foundation for 5G. We will look at the changes and evolution in the infrastructure as the industry evolves from the prior generation to standalone 5G. In addition, we will look at the impact of the maturity of cloud computing in Information Technology (IT) and its impact on the operators.

Here, we’ll cover the following main topics:

• Understanding NFV
• MEC-C-RAN (centralized/cloud RAN)
• O-RAN
• Using hybrid clouds

Understanding NFV

Network Functional Virtualization (NFV) borrows several concepts from enterprise IT to utilize server virtualization. This alleviates the need for custom hardware systems and appliances for various network functionalities. The goal of NFV is to decouple the hardware from the software stack for 5G. This reduces the dependence on custom-built hardware. In Figure 12.1, we show the high-level 5G core architecture to illustrate the relationship between the different concepts covered in this chapter.

NFV provides a great deal of flexibility to network operators to improve and enhance the capabilities of their network. This includes the ability to adopt virtualization for software applications. This allows independence from custom-built and expensive hardware in the form of specific physical appliances as part of the main network architecture. Companies such as Ericsson are driving the thought leadership around NFV: https://www.ericsson.com/en/nfv.

The adoption of...

Understanding MEC C-RAN

C-RAN is often used interchangeably with Centralized-RAN. C-RAN refers to cloud computing-based architecture for RAN and implements Radio Access Technology (RAT). RAN also connects the Core Network (CN) with User Equipment (UE). For 5G, one of the goals is to leverage public cloud infrastructure for RAN, which is already used in the mainstream IT world, and future-proof it for 5G. Where the cloud has too-high latency, an edge cloud is used.

C-RAN represents an architectural evolution over the following areas:

• An all-in-one macro base station for 1G and 2G networks
• A distributed base station for the 3G network

Historically, a RAN’s radio and baseband processing capability has resided in a base station. In C-RAN, we decouple the base station capabilities and processing power into Remote Radio Heads (RRHs), which exist in a distributed fashion at the cell site and the central Baseband Units (BBUs). The connectivity between the BBU and...

Understanding O-RAN

Open RAN or O-RAN is a vastly popular term in the 5G network world. It deals with the interoperability of open hardware, software, and interfaces for cellular wireless networks. The goal is to allow the use of Commercial Off-The-Shelf (COTS) servers and network equipment as opposed to customer hardware similar to those used in the base stations. In other words, O-RAN is a movement to standardize and allow for the interoperability of RAN’s building blocks (https://www.viavisolutions.com/en-us/solutions/o-ran).

O-RAN provides flexibility for operators to mix and match vendor equipment and not get locked into particular propriety hardware, software, and interfaces. See Figure 12.8:

Figure 12.8 – A simplified view of O-RAN

O-RAN promotes a more vibrant supply chain ecosystem for 5G compared to its predecessors due to the use of open standards for communication. This adds agility to the innovation process for the network...

Using hybrid cloud

In Chapter 3, Building Blocks – Cloud Native Infrastructure, we covered the topic of cloud-native infrastructure for 5G to drive the move from proprietary hardware to increased use of mainstream COTS products. This creates composable architecture with the ability to mix and match building blocks. These building blocks can be COTS hardware or microservices for the software stack. Figure 3.2 in Chapter 3, illustrates some of these components prevalent today. This also enhances the ability to port 5G infrastructure across different types of infrastructure building blocks. The focus on the public cloud landscape to support hybrid cloud comes in handy here.

The 5G industry landscape is gradually maturing and going through Non-Standalone (NSA) and Standalone (SA) evolutionary phases. (See the document located here: https://www.t-mobile.com/content/dam/tfb/pdf/TFB_TechTarget-whitepaper_SA-NSA-5G.pdf). This is given further context by the following descriptions...

Summary

In this chapter, we learned about the infrastructure required to support 5G networks. We looked at NFV, C-RAN, vRAN, and O-RAN, as well as the use of hybrid clouds for 5G networks. A thorough understanding of the infrastructure allows the development of a composable network over the life cycle of 5G.

In the next chapter, we will introduce the concept and architecture of network slicing for 5G. We will understand how network slicing acts as a differentiator for 5G. We will look at several use cases for slicing to better understand its applications.