Things are pretty easy in the world of wired Ethernet when it comes to speed. As a client, you get 100 Mbps or 1 Gbps on a switch port and the only potential limiting factor tends to be the size of your internet service provider.
However, Wi-Fi gets more complex, with endless data rate permutations depending on a lot of factors. Yet, you can still get a general sense of your speed by taking your device-stated data rate and cutting that in half. With mobile networks and discussions on the difference between 4G and 5G technology, however, things get real fuzzy real fast.
If you're trying to come to grips with what 5G networking will really amount to, it's important to grasp what 4G is. To understand the essence of what 4G is, you need to keep an open mind and not get hung up on the notion of exact metrics.
Mobile networking goals vs. reality
Let's start with the easy part: the G thing. G stands for generation, and each generation of mobile networking technology has its own loose descriptors and promises. Every iteration promises to be faster than the previous one by some multiplier, even if the previous generation's speed wasn't clearly defined. As I said, it's all fairly fuzzy.
4G works in a range of discrete frequency slices located between 700 MHz and 6 GHz. It's up to 10 times faster than 3G, which tops out at a few dozen Mbps maximum. The goals of 4G, as defined by the Telecommunication Standardization Sector of the International Telecommunications Union (ITU-T), are peak general speeds of 100 Mbps and, for non-moving devices like hotspots, speeds up to 1 Gbps.
In reality, you might get 10 Mbps, 7 Mbps or 43 Mbps. It's all over the place, and if a cell gets busy with a hundred or so connected and busy clients, it can feel very unlike 4G. Thankfully, it all works well enough in well-covered areas that most subscribers don't have to worry what speeds they are getting. Good is often good enough, and the ITU-T's goals don't often mean that much in practicality.
Next-generation services will blossom
Now let's consider the difference between 4G and 5G technology and what is gained with the new magic. The same frequencies 4G relies on are still in play, with additional allocations -- and potential allocations -- in different spectrum slices between 6 GHz and almost 90 GHz.
As with 4G, the ITU-T has stated performance goals for 5G: download speeds of as much as a whopping 20 Gbps, uploads as fast as 10 Gbps and super low latency. Additionally, 5G promises up to 1,000 times the bandwidth of 4G in its various permutations and support for between 10 times and 1,000 times the number of connected devices per cell -- depending on what those devices are. To that end, 5G is intended to support all our smartphones, hotspots and the predicted deluge of machine-to-machine utility devices.
That's all very impressive sounding, but in reality, none of these huge gains may ever be truly achieved. That said, as you examine the difference between 4G and 5G technology, 5G will be impressive, and its capabilities will be some order of magnitude better than 4G. Accept 5G's loosely defined parameters, and expect marketing departments to have a field day with the overall non-specific wonder of 5G.
At the same time, 5G will remain a metered service -- or pay as you go -- which adds complexity and perhaps barriers to how many IoT clients come to the 5G party.