Monica Paolini is the founder and president of Senza Fili. She is an expert in wireless technologies and has helped clients worldwide to understand technology and customer requirements, evaluate business plan opportunities, market their services and products, and estimate the market size and revenue opportunity of new and established wireless technologies.

How must wireline networks evolve to ensure the wireless side of an end-to-end network can deliver the expected promises of 5G? Much of the current attention focuses on the wireless side of 5G, or the Radio Access Network (RAN) side, where a significant increase in capacity and decrease in latency will change the user experience, man and machine, to enable new and innovative use cases.

However, 5G is much more than a new wireless access technology. 5G will fundamentally change how Mobile Network Operators (MNOs) build, operate, and use mobile networks, from the RAN to the data center where accessed content is hosted, and everything in between.

Consequently, wireline networks play a fundamental role to enable and optimize 5G end-to-end network performance and mobile user quality of experience, and must evolve in parallel with the wireless side of 5G. With the increase in traffic loads, lower latency requirements, and denser infrastructure, the wireline transport infrastructure must grow to avoid becoming the bottleneck in 5G networks.

Rather than a separation between the two domains, there will be convergence, where the demarcation between wireline and wireless will seamlessly blur into a unified end-to-end network.

The evolution of wireline networks is not limited to higher capacity and lower latency – which are needed to support new RAN capabilities – but to a deeper change in the relation between the wireline and wireless components in wireless networks. Rather than a separation between the two domains, there will be convergence, where the demarcation between wireline and wireless will seamlessly blur into a unified end-to-end network.

Access to content is predominantly wireless, and wireline predominantly fiber-based, but it is only through the convergence of the two that an optimized end-user experience is possible – in residential, enterprise and public networks – and that networks can deliver the reliability, security and performance that IoT applications need.

The use cases that 5G enables will change how wireless and wireline networks work together. At the access end, wireless will become even more prevalent than it is today in connecting people and machines through IoT. Wireline plays a crucial role in connecting end-users, radios, and content-hosting data centers together.

Today’s static, atomistic networks, where functions are fixed and tied to a location and an equipment element, will give way to pervasive adaptive networks that will be highly automated and optimized in near real-time.

Today’s static, atomistic networks, where functions are fixed and tied to a location and an equipment element, will give way to pervasive adaptive networks that will be highly automated and optimized in near real-time. As we move toward this goal, operators gain unprecedented freedom and flexibility. This will bring innovation driven by densification, virtualization, edge computing, network slicing, integration of multiple generations of wireless access technologies, and analytics to full fruition. But it will also increase the prominence of core functions – and the wireline connections that support them – in defining user experience.

How will wireline connectivity evolve to meet 5G requirements and user expectations?

“We're going to be capacity constrained if we're not using fiber in the network. Conventional microwave will give way to fiber,” Andy Sutton, Principal Network Architect, Architecture & Strategy, TSO, at BT told us. But the change goes further.

Kostas Chalkiotis, Vice President Mobile Access, Technology & Innovation, at Deutsche Telekom added: “We need more than just fiber connectivity. We need to change the architecture, the topology, even the media that we are using for our transport network today. Both fronthauling and backhauling have huge challenges on both throughput and latency.”

“We're going to be capacity constrained if we're not using fiber in the network. Conventional microwave will give way to fiber.” - Andy Sutton, Principal Network Architect, Architecture & Strategy, TSO, at BT

Regional Adoption of 5G Around the World
In Europe, the evolution of the wireline connectivity started long ago with the transition from wireless backhaul to fiber, which is increasingly necessary for the 4G infrastructure ahead of 5G. A more cautious approach to 5G than in Asia and North America, will make the overall transition to 5G slower, but European carriers may turn this to their advantage because they will have more time to get their networks ready for it, and they will be better prepared for the disruption that 5G as a major technology advance will bring.

As in other regions, however, mobile operators see the transition to 5G as necessary to unlock the performance potential of new technologies and revenue potential from new services. But European operators appear less optimistic that 5G use cases are sufficiently compelling to justify the investment and upgrade effort, or that they will require 5G.

Some proposed 5G use cases can actually run on 4G, but only if adoption is very limited. Wide-scale adoption of new use cases, such as IoT-based Smart Cities, will require the scalability of 5G. Although use cases will generate additional revenues (e.g., IoT applications), 5G is unlikely to dramatically raise subscriber revenues in the near-term. A better reason to deploy 5G is that it is a more cost-effective technology – i.e., the per-bit costs are lower than for 4G, and even more so for 3G.

We just published a white paper, 5G in Europe: More than a wireless upgrade. The wireline network evolution in preparation for 5G which looks at how the transition to 5G affects wireline backhaul, fronthaul, and the emerging converged-haul variations. We also consider the impact of those changes on how mobile operators transport traffic across their networks, and how they can plan for them as they transition to 5G. We specifically look at the implications for European mobile operators, with their more cautious approach to 5G compared to that of their Asian Pacific and North American counterparts.

Want to hear more? Watch Ciena’s on-demand webinar: Preparing your wireline network for 5G to learn more and you’ll also get a free copy of the paper.