5G Network Architecture and 5G Wireline Network Convergence

The Performance of 5G Is Directly Impacted by Transport

 - Overview

The 3GPP standards that underpin the 5G network architecture were introduced by the 3rd Generation Partnership Project (3GPP), an organization that develops international standards for all mobile communications. The International Telecommunication Union (ITU) and its partners define the requirements and timelines for mobile communication systems, defining a new generation approximately every ten years. 3GPP develops specifications for these requirements in a series of releases.

The 5G technology architecture presents a major advance over 4G LTE (Long Term Evolution) technology, which follows 3G and 2G. There is always a time slot for the 5G journey. During this period multiple network generations existed simultaneously. Like its predecessors, 5G must coexist with previous networks for two reasons:

• Developing and deploying new network technologies requires significant time, investment, and collaboration of key entities and operators.
• Early adopters always want to get to grips with new technologies as quickly as possible, while those who have already made significant investments in large-scale deployments of existing network technologies (such as 2G, 3G, and 4G LTE) want to leverage those investments for as long as possible, Of course until the new network is fully viable. (Note that 2G and 3G networks are being phased out to make room for 5G deployments.

- Traditional Mobile Network Domains

Traditionally, mobile telecommunications networks consist of 4 major domains:

• The device, such as a smartphone, a tablet device, a router etc. which is also called the User Equipment. 
• The Radio access network (RAN), which uses radio frequencies to provide wireless connectivity to the devices. 
• The core network (CN), which provides coordination between different parts of the access network and also provides connectivity to the internet. 
• The transport network, which provides connectivity between the RAN and the CN.

- Key Advantages of 5G Technology

The network architecture of 5G mobile technology has greatly improved on the basis of past architectures. Large cellular dense networks enable huge leaps in performance. Additionally, the architecture of 5G networks provides better security than today's 4G LTE networks.

5G technology has three main advantages:

• Faster data transfer speeds, up to multi-gigabit/s speeds.
• Greater capacity to power a large number of IoT devices per square kilometer.
• Lower latency, down to single-digit milliseconds, is critical in applications such as connected and autonomous vehicles in ITS applications where near-instantaneous response is required.

- The 5G Network Architecture

The primary goal of previous generations of mobile networks has been to simply offer fast, reliable mobile data services to network users. 5G has broadened this scope to offer a broad range of wireless services delivered to the end user across multiple access platforms and multi-layer networks. 

5G is effectively a dynamic, coherent and flexible framework of multiple advanced technologies supporting a variety of applications. 5G utilizes a more intelligent architecture, with Radio Access Networks (RANs) no longer constrained by base station proximity or complex infrastructure. 5G leads the way towards disaggregated, flexible and virtual RAN with new interfaces creating additional data access points. 

The 5G architecture will have a significant impact on today’s mobile networks, physical networking, computing facilities, hosting and deployment systems, and service and infrastructure orchestration. Whole of the 5G system includes a user terminal which is supported by autonomous radio access technologies consisting of cells, towers, systems that connect the mobile users and wireless devices to core networks.Core networks, on the other hand, are responsible for the handling of mobile connections as well as Internet connections. 

Cutting-edge technologies and a redesigned wireless network architecture are the foundation of 5G architecture. 

- Optical and Wireless Convergence for 5G

5G is a Network of Networks. 5G networks will combine numerous wireless technologies, such as 4G LTE, Wi-Fi, and millimeter wave technology. 5G will also leverages cloud infrastructure, intelligent edge services and virtualized network core. Compared to previous technology generations, 5G is a network of networks or system or systems. Higher level of interconnectedness means factoring in all kinds of telecom infrastructure. The previous ones were focused on terrestrial systems - 3G and 4G - but now this concept of integration is really in place.  Satellite has been included into 5G standards, and now can become an integral part of 5G. One of the main differences between 4G and 5G is that 5G will need many more base stations to cover the same geographic area - three to five times as many base stations - be they connected to towers, buildings or lamp posts - will be needed to cover an area with the amount of capacity and speed demanded. 

"To bring 5G to life, we need to deploy hundreds of thousands of cell sites. Current manual processes require in-person site visits, but we’re using machine learning to create a “virtual world” that describes its environment - poles, buildings, building materials, foliage - to help operators determine where cell sites can be placed without requiring a site visit. This technology also helps us identify faults in our towers." - (AT&T Labs - Research)   

- Transport Networks Have To Evolve As 5G Scales

When considering 5G, the current focus of industry discussion is largely on radio access - certainly a key element given that it connects the end user with the network. But, in addition to enhancements to the Radio Access Network (RAN), making the most of 5G requires investment in new core infrastructure as well as in the transport network, the vital link between where services are created and where they’re passed onto subscribers. 

It is clear that any 5G system will integrate optical communications, which is already a mainstay of wide area networks. Using an optical core to route 5G data raises significant questions of how wireless and optical can coexist in synergy to provide smooth, end-to-end communication pathways. Optical and Wireless Convergence for 5G Networks explores new emerging technologies, concepts, and approaches for seamlessly integrating optical-wireless for 5G and beyond. Considering both fronthaul and backhaul perspectives. 

One of the biggest challenges the mobile industry faces is how to accommodate the extraordinary increases in data volume and performance expectations over the next couple of decades. We’ll have to look at the entire system from end to end. The underlying transport network provides the all-important connection from the Radio Access Network (RAN) to the packet core, which subsequently makes the connection to the public Internet. Changes in the transport network architecture tend to get less attention than developments in radio access technology, but they are no less important.  Distributed antenna systems (DAS), remote radio heads (RRHs), and small cell base stations will all be part of 5G deployments and all place different requirements on the transport network.