Contentious enough to cause diplomatic ructions, 5G is the mobile technology upgrade that continues to hit the news.
For consumers, the next generation of mobile networks promises to deliver faster connections, fewer delays and new services.
For telcos, the upgrade will allow many more connections in a given area, and opens up the chance to earn extra revenue from the "Internet of Things", connecting anything from your fridge, to your car, or city streetlights to the mobile network.
But for now, that's all in the future. Despite the increasing noise, 5G remains a work in progress.
However, trawling through the standards documents and vendor announcements provides a reasonably good idea of what to expect.
The first technical specification for 5G will arrive in a document called the 3rd Generation Partnership Project (3GPP) Release 15, due in April this year.
Developers have already started working on building 5G network equipment, mainly for testing, based on Release 15.
The final Release 16 is scheduled to come out a year later in April 2020. At that time the two releases will be submitted to the International Telecommunication Union (ITU), an ancient and august United Nations body in Geneva.
The ITU will see how the releases adhere to its International Mobile Technology specification for 5G (IMT-2020).
This process is largely a formality, but goes to show the level of complexity that's required to navigate international telecommunications bureaucracy at the technology level.
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Also, there's good reason for the telco industry and the ITU to move carefully: the technology must be substantially better than 4G is now, or subscribers won't bother to upgrade.
As well, 5G must offer cost savings and capacity upgrades for telcos and has to last long enough into the future, and create new revenue streams, to pay for itself.
Building mobile (and fixed) wireless communications infrastructure for entire countries while your revenue base is being eroded by operators who deliver their services over the internet is a huge challenge for telcos.
What makes a network 5G?
Everyone wants faster connections, but the radio frequency spectrum used by wireless data signals is a finite resource.
There's only so much capacity you can wring out of a data channel, even with very complex and clever new modulation techniques that pack in more information per Hertz.
What's the solution? Add more bandwidth, and 5G will do just that — up to five times as much as 4G networks can avail themselves of.
Using multiple radio frequency ranges for increased bandwidth is already here.
Called channel aggregation (CA), 4G can use five bands of up to 100 megahertz of spectrum to boost data speeds.
But 5G takes that up a notch by adding more frequencies in ranges that aren't used for mobile devices now, including millimetre wavelengths between 24 and 86 gigahertz (GHz), and lower ones below 6GHz.
Telcos have spent up large on management rights for spectrum recently, with hundreds of millions of dollars flowing into government coffers.
It's the millimetre wavelengths that will provide the big speed increase: while the theoretical speed of a 4G connection of is 1 gigabit per second (Gbps), IMT-2020 says 5G needs to deliver 10Gbps, and peak speeds of up to 20Gbps.
While that sounds impressive, there are several caveats: millimetre wavelengths don't travel far, don't go through objects very well and scatter easily — including when it rains — compared to longer frequencies.
Lots of small new millimetre wave access points with a reach of a few hundred metres need to be deployed for the high 5G speeds, and that won't happen everywhere. Outside millimetre wave coverage, users can expect slightly improved 4G speeds.
As with 4G, 5G will mix it up with WiFi in the unlicensed 5GHz spectrum. The new WiFi 6 standard will come out next year, providing 1-2Gbps real-world speeds, which is as fast as most wired networks currently.
The high numbers above should be compared with the real-world 100Mbps performance experience for each user that 5G is required to provide.
Interestingly, former Vodafone chief executive Russell Stanners expects typical 5G use to be relatively modest by 2020, at just 10 to 20GB per month.
That compares to Chorus' latest usage figures for the ultra fast broadband (UFB) fibre network, which say the average New Zealand household went through 235GB in December last year. As a side note, Chorus is also trialling 10Gbps UFB fibre connections, no doubt to unnerve the telcos ahead of the 5G launch.
What most users will notice more than super-high theoretical speeds is the improved "latency" — in other words, shorter delay in data transmissions — that 5G promises.
Latency is what makes 3G networks so annoying to use if you're accustomed to 4G.
Today's apps and websites use a huge amount of small data connections, and the less delay a network adds to those, the snappier the connection will be.
Here, 5G must deliver a 30 to 50 times improvement, dropping the latency from 30-50 milliseconds for 4G, to just a single millisecond. Improved electronics, radio technology with multiple active aerials and direct device-to-device communication that can do some of the computing work now done at the core of the network will help achieve this.
The first release of 5G will be non-standalone, meaning it will run alongside 4G networks.
Later, from next year and onwards, is when we'll get the low delay and machine-to-machine communications that require the full standalone 5G core to be rolled out.
What's in it for telcos?
Forking out big money on spectrum licences and buying and operating costly infrastructure is a gamble for telcos which face competition from internet-based "over the top" providers.
Those providers have eroded the traditional business of selling minutes, and they don't have to invest in physical networks.
But moving to 5G provides benefits for telcos such as having many more customers, or rather more devices, per cell site sector.
Whereas 4G specified up to 10,000 connections per square kilometre, 5G ups that figure to one million.
This will allow large-scale deployment of wireless "Internet of Things" (IoT) devices connected via 5G, and that's where telcos hope to eke out a new revenue stream from the technology.
Masses of small, inexpensive wireless sensors and actuators with long battery life for utilities, smart cities, and homes can be leased to subscribers at a low cost with 5G.
They will use built-in eSIMs and take advantage of 5G's software defined networking and network function virtualisation — called "network slicing".
With 5G, telcos can "slice up" their 5G networks so that one virtual part of it handles IoT devices, which don't use lots of bandwidth, aren't sensitive to delays and don't use much power.
Other virtual parts of the 5G network can handle mobile subscribers, another can be configured to talk to self-driving vehicles, and more, all over the same physical infrastructure.
IoT connections also have to be very reliable and provide ultra-accurate location information for self-driving vehicles, and this is a key 5G requirement.
5G also continues the re-engineering of telco networks to become fully internet protocol (IP) based.
When you look at the new capabilities 5G brings, and the IP-based structure, you start to understand why our spy agencies worry about the new technology's security.
5G will be everywhere, including in critical infrastructure such as power and water systems.
Across the Tasman, the head of the Australian Signals Directorate, Mike Burgess, defended banning Chinese vendors Huawei and ZTE from the country's 5G networks as a risk management exercise.
Simply put, companies from countries with strategic objectives that clash with those of Western nations can't be trusted to supply 5G equipment.
China is not happy with Five Eyes nations, including New Zealand, and European countries banning its telco companies from 5G, and tensions over the issue will continue to flare this year.
Pervasive 5G coverage that offers very accurate location information for precise user and device tracking, thanks to small cell sizes, also has the potential to spark privacy concerns.
Unravelling the abbreviations
Mobile telecommunications terminology is confusing and difficult to follow, with lots of indigestible acronyms.
The go-faster tech for 5G is called eMBB (enhanced Mobile BroadBand), and the quicker response and network reliability is URLLC (Ultra Reliable Low Latency Communications).
Good luck trying to get customers to remember those abbreviations, or mMTC (massive Machine Type Communications) and other obscure terms.
That's why upgrades are supposed to be marketed with a number and "G" for Generation, so subscribers get a rough idea of what bundle of capabilities they're buying into.
At least that's the theory. In practice, telco marketers have rendered that simple concept almost meaningless. The older 3G ended up with 3.5G, 3.75G and 3.9G variants as data speed upgrades were added.
Similarly, 4G had an upgrade to 4.5G. Now, 4G is also known as Long Term Evolution (LTE). As new features have been bolted on, many of which will make it across to 5G, telcos and their equipment vendors have started using "LTE Advanced" and — no joke — "LTE Advanced Pro".
Telco marketing departments like to jump the gun to make it look as though they're first with the new tech, even though 5G is not officially ready to be released.
For example, United States telco giant AT&T sent out an update to some devices that changed the network connection icon from 4G to 5GE. The "E" stands for Evolution and AT&T added go-faster features such as support for multiple aerials (4x4 MIMO, which stands for multiple input, multiple output) and packing more information in the signal itself.
However, the new capabilities have been available on other 4G networks for a couple of years already and AT&T was roundly slammed by competing telcos and tech media for the 5GE stunt.
Closer to home, Spark has set up a 5G test lab with LED streetlights that incorporate Internet of Things technology, and Telstra boss Andy Penn boasted that the telco will have 5G handsets ready this year, having stitched up some exclusive deals with manufacturers.
Real and bogus early announcements apart, 5G is an exciting technology upgrade for businesses and end users alike.
For users, speed is the key
Fifth-generation wireless technology may one day handle sci-fi tasks like guiding driverless cars, but today's consumers are more concerned with making their phones work faster.
That fact wasn't lost on mobile carriers at the giant CES consumer technology show in Las Vegas last week.
Fully-fledged 5G networks are still more than a year away in the US, but selling investors on the idea and touting eye-popping speeds is every bit the game — even if it means slapping that label on technology that isn't really fifth generation.
For example, AT&T will rebrand recent models of 4G Android phones as 5G Evolution or "5G E", a transitional step intended to reflect speed and capacity upgrades to the carrier's current network.
And if it's noticeably faster, mobile customers might not split hairs about 5G definitions, says BTIG analyst Walt Piecyk.
"The broad availability of 'real 5G' could be years away, providing AT&T with a window of opportunity to surpass Verizon's historical dominance as the wireless network leader in the US," he says.
The mobile carriers are touting benefits such as virtually eliminating "latency" — those annoying delays when you're trying to connect — enabling services that aren't possible now, and supporting many times more connections than 4G within the same service area.
Among AT&T's plans are deals to help cities automate some services, and embedding more communications technology in cars.
But as well as the potential consumer benefits, 5G has also set off warning bells among US executives and the military.
This month, a retired US general said China's desire to dominate new wireless technology posed a global threat that should be thwarted by a new, secure network.
China will gain a capability for mayhem and mass surveillance if it dominates advanced 5G networks that link billions of devices, retired Air Force Brigadier General Robert Spalding said in a memo obtained by Bloomberg News.
"The more connected we are, and 5G will make us the most connected by far, the more vulnerable we become," said Spalding, who left the National Security Council last year.
Beyond the security implications, the building of 5G could unleash many billions of dollars of spending on product development and networks.
And for carriers, 5G can open the door to sales of advanced services.
- The Washington Post
- Juha Saarinen is a commentator and Herald columnist who has been covering technology for more than 20 years.