Image: The Spinoff
Image: The Spinoff

PartnersJuly 7, 2020

Do you know how the internet works?

Image: The Spinoff
Image: The Spinoff

In the 90s, the so-called information superhighway was more of a dirt road. Now it’s a multi-lane motorway. Vodafone NZ’s Sharina Nisha explains the technology that makes it all possible.

They used to call it the information superhighway. Back in the heady days of the 1990s, the term was used to describe the burgeoning potential of telecommunications technology, and particularly the internet. 

While the term has long been retired (along with “surfing the web”), it has become more accurate every year. That original superhighway now seems much more like a dirt road, and the development of the infrastructure that technology runs on has allowed it to be paved, new lanes and onramps added, until it’s become a massive motorway with millions of commuters every day. In fact, as the recent lockdown showed, for many people getting online became much more important than being able to get into the office at all.

The massive changes in workplaces, education, entertainment, commerce, and almost every other field of human endeavour that have taken place since the 90s have all relied heavily on telecommunications technology. So how does the network technology that keeps our lives running actually work? The Spinoff asked Vodafone NZ’s head of platforms, Sharina Nisha, to explain the infrastructure behind the information superhighway. 

First of all, what exactly does the internet run on, in terms of technological hardware?

The best place to start is with the first point of connectivity – or how you connect to the internet. There are two main ways, depending if you’re on a mobile connection or a fixed connection with a modem and cabling back to the network. If you’re on mobile it sends a signal to a cell tower, and if it’s a fixed connection that might be via a copper or fibre cable. 

Within the Vodafone network, there are a couple of components. There’s the core network, or the “brain”, which is all the smarts – like who you are, what plan you are on, all your subscription details, how much data you have access to. 

Then there’s the transport network, which has all the fibre connections between networks here and internationally. Much of the data we consume is stored around the world. A lot of information is stored in caches here, so when there’s a request it’s already local enough to be picked up easily. But generally data is hauled around on very big fibre networks up and down the country, and then across to international destinations. Those cables, like the Southern Cross Cable or Hawaiki Cable, traverse the entire Pacific Ocean to connect the US, Pacific Islands, New Zealand and Australia. 

And what are those international cables made of?

These are fibre optic cables, which are made up of very thin strands of glass that carry light beams. They aren’t necessarily just one straight line of cable either – rather, they’re more like a rail network with multiple landing points, so they can transport data at lightning speed.

What is it that makes fibre faster than another material like copper? 

Essentially, fibre technology sends information as rapid pulses of light. Copper uses electromagnetic fields and the characteristics are quite different. Think about fibre as light from a laser beam – it can travel up to 200km without any interruption or loss of connection. In other words, it’s incredibly useful for delivering data over long distances – to use the train analogy again, it’s more like an express line from the outer suburbs to the inner city.

Copper, by contrast, is more like wiring that electricity travels along at a particular frequency. But copper’s electromagnetic field is susceptible to higher frequencies, so there are more losses, especially the further away from the point of exchange that you get.

Vodafone NZ’s head of platforms, Sharina Nisha (Photo: Supplied)

Why are there caps on data? Shouldn’t it be easy once the infrastructure is in place to send as much information as you want along it?

Not necessarily. This is because the system has many parts – from the customer’s device, through the core and transport network, the international connectivity – at all of those points there are limits to capacity. This means that there is limited space, which has to be allocated accordingly, and we need to build more capacity as data use increases. 

How do telecommunications companies plan for that space to be allocated, in a world where more and more information is going online? 

In short, we plan a long way out. Telco companies project future growth by looking at the internet plans that are being sold, the number of customers we have, and what customers are doing with their devices. Capacity is built so that the telecommunications company is about 12-24 months ahead of projected demand. 

But what if there’s an unexpected spike in demand?

That can happen, and in fact was seen very recently when New Zealand went into alert level four lockdown. Everyone was stuck at home, and data use went through the roof, increasing by 20-50% on average. Fortunately, in the case of Vodafone we had already built a lot of spare capacity into the system, so it wasn’t such a struggle. 

Last year we had to get ready for a moment in which hundreds of thousands of people all sat down at the same time to stream a Rugby World Cup game, which itself required an unprecedented level of capacity. Who knew that would prepare us for managing a global pandemic. 

When people talk about changes in generations of networks, from 2G through to 5G, what does that mean?

In the mobile network, the second generation (2G) technology was predominantly a voice network, so it was good for making calls, basically. That has now evolved into a 4G/5G network where the technology allows telcos to carry a lot more data on the same amount of radio spectrum. Similarly, the fibre optic technology has evolved and much more data can be carried on a single wavelength. In terms of numbers, it is now possible to get up to 17 terabits of throughput on a single pair of fibres – that’s equivalent to over 700,000 channels of 4K TV streaming at the same time or more than 100 million simultaneous phone calls.

How does the information get from the modem in one corner of the room to a laptop in the other corner?

Wifi is the commonly used technology, and it uses radio waves, just like a cell tower – the 2.4 gigahertz spectrum or the 5 gigahertz spectrum. 2.4 GHz is more commonly used and can go longer distances, whereas 5 GHz is cleaner but goes shorter distances. It is best to spread the in-home usage across both these channels.

The Hawaiki cable landing at Mangawhai Heads in February 2019 – a fibre optic cable that connects New Zealand, Australia, American Samoa, Hawaii and the US west coast

Should I be worried about cellphone towers turning up near my house? There are a lot more of them around these days.

As people have been using phones a lot more, for example streaming YouTube videos while they are on the bus, we’ve needed to build additional cellphone towers to add capacity to the network. In Auckland, for example, the number has gone from just a few to hundreds in the space of a decade.

But in short, no, they’re not dangerous. Basically a cell tower is a giant wifi transmitting device. It’s the same as what you have in your house, it’s just transmitting more power to more devices. It’s absolutely safe, because it uses non-ionising rays to transmit data. These have been used for a long time, and use a similar spectrum to what radio is broadcast over. On the flip side, an example of an ionising ray would be something like an X-ray – you wouldn’t want to spend more than a short amount of time in one of those.

What if the towers are transmitting for 5G? 

There’s no difference  – 5G (as the fifth generation mobile network is known) is newer technology, so it is better and more efficient at doing the job than previous generations of networks. It can be normal to feel uneasy about new infrastructure going up near you, particularly if there’s a sense of it being unknown. But think about it this way – setting up cellphone towers is skilled engineering work, and real people do it for a living. If 5G really was dangerous, they’d likely take those skills and go and do a different job.

There have been arson attacks on cellphone towers by people worried about the effects of 5G. What effect does that have on the wider infrastructure?

Here, it makes sense to stick with the analogy of roads, and network capacity as a set of lanes. A crash on one lane won’t necessarily stop traffic, but it might slow it down. A crash that takes out all of the lanes means a whole city could grind to a halt. It can mean cutting away people’s lifelines to the rest of the world. 

When the lockdown started, all of a sudden people desperately needed connectivity to work or study from home, or keep in touch with their families. Technology and infrastructure can make our lives a lot easier, but the more we rely on it, the more dangerous it can be to take it away.

Keep going!