ITP Techblog

Brought to you by IT Professionals NZ
« Back to Government

Let's talk copper

Paul Brislen, Guest contributor. 30 August 2021, 11:06 am

There seems to be some confusion about copper lines and how they work, not to mention why we're moving away from them to newer technology, so I thought I'd have a go at explaining it all.

Copper lines were the mainstay of the telecommunications world for almost 200 years. Starting in the mid-1800s with the telegraph, copper lines have been strung around the world providing users with binary information ever since.

Those early dots and dashes are identical to today's high-speed broadband connections in every way except one: speed. Today's networks send trillions of dots and dashes per second, something the copper lines could never do.

Copper lines use huge amounts of electricity to push signals up and down them, which means you need a lot of shielding to avoid interference, which makes it more difficult to send signals through. You get the picture - the power costs for VDSL are about six times the costs for a similar length of fibre.

On top of that, the further away from the exchange your phone was, the worse the signal. That might be OK for voice calls, but once you start trying to use them for internet access line quality becomes crucial. Too many users were told they were too far from the nearest exchange to get any kind of internet connection, and with the introduction of home computers, that became a major problem.

The resilience of copper

Copper lines did have one thing going for them - the power to run the call was sent from the exchange down the line. Homeowners and businesses weren't expected to plug in their landlines into a power source at their end - it was done for them. That gave users great peace of mind, especially when they needed to call emergency services. You could pick up the handset and be almost guaranteed to hear a dial tone.

That all ended about 15 years ago when the industry introduced roadside cabinets to improve the broadband connection for customers by reducing the distance to each household. Since then, each cabinet and exchange includes battery back-ups to power the lines, which means in the event of a disruption to the power supply (an earthquake, for example) even users of landlines will have a couple of hours of battery life before the phone goes silent.

Today there are new technologies that are rapidly replacing copper lines that provide improved capacity and reduced maintenance overheads.

That's good, because today's user has much higher levels of expectation around what they do with their connections than ever before.

If you want to talk to someone on the far side of the world, you don't have to bite the bullet and hope the toll call won't be too much - you use Zoom and get to see them in full HD quality video while chatting. Or you can play a game online with them, or you can both watch television together, or transact business, make music, do your banking, go shopping, learn, teach - the options are endless.

A glimpse of the future

All of these things require bandwidth. They require increased capacity and as they become more of an essential item than a 'nice to have', it's important we have a network that keeps up with demand.

Network deployment around New Zealand continues apace, and we are connecting far more places to a far better infrastructure than we ever have before. Our experience during COVID has been a glimpse into the future: we can work remotely, we can lock the doors but carry on being connected, and that's important for our economy, but just as important for our community and our society.

The next few years will see the digital economy in New Zealand race ahead in terms of value but also in terms of jobs and opportunity, especially in regional areas that have struggled in the past because of their isolation - something good communication networks can help overcome. If we want New Zealand to take its place on the world stage we have to have the network to back it up. Thankfully, work is already well underway on that front.

Paul is the  New Zealand Telecommunications Forum's CEO.


You must be logged in in order to post comments. Log In

Citation Needed 31 August 2021, 10:25 pm

"Sending pulses of electricity up and down a copper line heats the metal and cools it repeatedly, and leads to degeneration over time."

That's a fascinating point. Must be a pretty crankin' landline or DSL modem you have there. Are there any reputable scientific studies that show this is happening?

Web Development by The Logic Studio