5G And Fibre

Not at all, is the answer from Zoltan Miklos, general manager of network planning at MTN South Africa. “When people talk about 5G, they often approach it from a radio perspective,” says Miklos, “but 5G is really an end-to-end architecture. You need to make sure the various building blocks of the network support 5G and its use cases. The radio base station elements, radio spectrum, high-capacity backhaul to the core network, the core network and supporting systems are all critical for 5G.”

Miklos says the main metros will use fibre predominantly to support 5G deployments, because this is where infrastructural development has been concentrated. Where fibre is not available, high-capacity microwave links are used, which can support bandwidths in excess of 1Gbit per second. “Ideally, you need 10Gbit per second connectivity to a 5G-enabled mobile base station site, which fibre enables.”

Further enabling 5G and the required national network capacity is fibre technology called dense wavelength division multiplexing (DWDM), which allows data signals from a variety of sources to share a single optical fibre. “DWDM is used in the national optical transport network, which interconnects our core sites,” explains Miklos. “This high-availability core carries mobile, enterprise and wholesale traffic.”

The business case

The interplay between fibre and 5G is a complex one, both on a technical and business level. “Fibre won’t be deployed everywhere in South Africa, especially to the end user,” says Miklos. “The business case is difficult: low user density scenarios and high cost structures don’t allow for it to be deployed in some areas. There are long-haul fibre routes outside the metros that connect remote locations. But for clusters that are far from fibre infrastructure, long-haul microwave systems using multiple hops are required to provide high bandwidth connectivity to these clusters.”

Key to deployment considerations, says Miklos, is the fact that capacity requirements vary between rural low-density areas and urban areas. “Ideally, if the capacity requirements grow over time, fibre will be planned to those locations.”

While fibre deployment is much more widespread in urban areas, it still requires capital investment prioritised by required bandwidth and the density of that demand. In some situations, 4G and 5G provide an opportunity to service fixed connectivity requirements. “It is optimal to deploy fibre as deep as possible, then have a wireless tail,” says Miklos. “A smart capital approach we follow is once there is sufficient densification of demand, then you extend the fibre network to the user to augment the wireless infrastructure.”

SD-WAN: a paradigm shift for network management

Modern businesses find themselves juggling sprawling, complex, diverse systems and applications, making reliable, comprehensive network management crucial. Software-defined wide-area networking (SD-WAN) presents a centralised solution for network management with the potential to greatly simplify the process. “A key benefit of SD-WAN is predictability,” says Julian Liebenberg, chief of converged communications at BCX. “In the previous dispensation, it was possible to configure two devices on a network in such a way that they could not establish communication with each other. Now this is impossible: you’re using a centralised controller to establish connectivity between these devices, so by default your devices can communicate.”

Liebenberg says this represents a paradigm shift in terms of network management: you don’t need someone to configure the network, because it configures itself. What this means is that network management becomes more of a business than a technical case. “The network becomes part of your intelligence. It collects information about business transactions. You start to think about how to get more out of the network. Your applications can learn from it: perhaps sales of a product line are picking up in a given branch, so your application needs to behave in a different way. This provides far more real-time data than looking at month-end reports, but only if someone takes the time to program the network to givethose values.”

Supporting your strategy

Although there is a glut of vendors offering quality SD-WAN solutions, Liebenberg says choosing one can be quite tricky. “Firstly, it is not interoperable. Each vendor is proprietary; you can’t pick two and run them concurrently, so you need to make the right decision first time.”

A second consideration is to what degree the SD-WAN supports your software-defined networking (SDN) strategy, as very few vendors do this comprehensively. “SDN covers the LAN – wireless and cable, which is software-defined access. Then there’s the SD-WAN in the middle. And at the top end, you have the infrastructure where your applications reside, be that in a hyperscaler in your own data centre or a private cloud. Those are the three environments of SDN, and you have to ask yourself if the vendor you’re dealing with gives you a strategy across all three areas.”

Security is also an important factor. “If you deploy SD-WAN over a private underlay – such as metro ethernet or MPLS – then you are typically less concerned about security, as even though you connect all your branches, you apply security at a central firewall.” However, if you deploy over any form of public internet (for example broadband) – an increasingly common scenario during lockdown – then every branch becomes exposed. “At this level, though, most leading vendors are able to address these concerns. Many are PCI DSS compliant, which is the credit card industry standard, a very high level of compliance.”

Connecting business parks

Virtually no business can function without internet these days, so it goes without saying that high-speed internet connectivity for business parks is essential. “Fibre has almost become a commodity, like water or electricity,” says Gary Webster, head of wholesale department at Metrofibre. “A couple of years ago, clients would contact landlords a couple of months before they moved in to check if they had fibre. These days it’s expected.

“We’re in an environment where cloud computing is becoming more and more prevalent, and the COVID-19 crisis has only reinforced that,” continues Webster. “Working from the cloud makes fibre an absolute necessity. A key advantage of fibre over previous access technologies is high-speed synchronised connectivity, meaning the upload and download speeds are the same, which is critical for cloud applications.”

Making the right choice

According to Webster, whereas in the past individual companies within business parks would approach their preferred internet service provider (ISP) when they needed to get connected, more business parks and property developers are using Open Access fibre network operators (FNO) to fibre up their business office parks, thus offering the tenant the ability to choose the ISP of their choice. “We implement a turnkey solution, from planning and surveying to managing marketing and sales. This mitigates the risks of having multiple ISPs lifting up paving, potentially cutting existing lines and creating havoc.”

There are ancillary benefits to a good fibre service provider, including Voice over Internet Protocol telephony and enhanced cyber security, but Webster says that when making the choice, a crucial question landlords or property developers should be asking is whether or not the FNO is an open-access provider. “You don’t necessarily want to be stuck with one specific provider, and you need to establish if the ISP offers uncapped, unshaped services. It’s important that tenants and developers understand all the terminology to ensure that the service they provide to their tenants is open-access, uncapped and includes the desired ancillary benefits.”