When the first cellular communications protocol was launched in the UK, mobile phones evolved from science fiction theory into an attainable reality.
In the early 1990s, the Global System for Mobile protocol was developed to underpin the second-generation of mobile communications – 2G.
Switching from 1G’s analogue services to 2G’s digital connections ensured calls were clearer and more stable, while 2G also supported new technologies like encrypted text messaging.
As home internet services gained critical mass, phone manufacturers and network operators began looking for ways to get their handsets online.
The result was a system known as Enhanced Data rates for GSM Evolution, or EDGE – launched in the early Noughties and informally known as 2.5G.
This built on the success of an earlier upgrade on 2G known as GPRS, or General Packet Radio Services, which was up to twice as fast as the dial-up internet connections of the day.
EDGE was twice as fast again, with a theoretical maximum speed of 0.2Mbps – quick for the time, but leisurely by modern standards.
When Hutchison launched 3G in 2003, it might have seemed self-evident that the 2G mobile networks would be rendered obsolete.
Yet they weren’t. And they still aren’t.
To this day, smartphones use the 2G network established almost thirty years ago for basic services like text messaging and photo messaging – SMS and MMS respectively.
If you’re in a remote area, or struggling to get 4G/5G connectivity, your smartphone screen might display a G (GPRS) or E (EDGE) symbol.
These indicate the device has dropped back onto the 2G network for data transfers.
Living on the EDGE
Newer generations of smartphone connectivity have focused on speed, attempting to match the performance improvements seen in landline connectivity over recent decades.
Yet 4G and 5G aren’t really doing anything 3G didn’t do, or EDGE/GPRS before it.
Indeed, in many respects, the old ways are still the best.
Because the 2G network isn’t burdened with torrents of streaming and gaming traffic, it remains effective and dependable in terms of delivering SMS and MMS.
In rural areas, GPRS/EDGE are dependable fallbacks, and 2G is also used by many Internet of Things devices like smart meters. It even supports some international roaming services.
As such, 2G is likely to remain in service long after 3G has been consigned to history.
Vodafone is already beginning this process, aiming to have 3G switched off by 2022. Other networks are expected to follow suit, across a slightly longer timeframe.
Two by four
Discussions have been taking place between the four big UK mobile networks about the feasibility of switching off the 2G mobile networks in favour of exclusively 4G/5G services.
It’s a measure of the old protocol’s durability that no consensus has been formed about migrating voice calls and text messaging away from 2G.
While 4G now carries 85 per cent of the UK’s smartphone data traffic, and 3G/EDGE are only used in remote regions, 2G remains necessary as a backup.
Indeed, a report from the UK Spectrum Policy Forum (published last month) suggested it might be 2030 before we can relinquish 2G connections entirely.
Network operators will need to take a number of steps before then, such as launching replacement radio access technologies with comparable levels of coverage and reliability.
A great deal needs to happen behind the scenes before the UK’s remaining 2G mobile networks can be switched off without affecting millions of consumers.