What is Latency?
People often make the mistake of confusing internet speed for bandwidth. It’s not their fault, though. Internet service providers claim that their connections are as fast as 35 Mbps, or that their speeds are 20% faster than their competitors. But the truth is that your 25 Mpbs connection has little to do with speed, and more to do with how much data you can receive every second.
True internet speeds comes down to a combination of bandwidth and latency. What is latency? The definition for latency is simple:
Latency = delay. It’s the amount of delay (or time) it takes to send information from one point to the next. Latency is usually measured in milliseconds or ms. It’s also referred to (during speed tests) as a ping rate.
How is Latency Different from Bandwidth?
Well, for one thing latency is a way to measure speed. Ironically, bandwidth isn’t, despite the fact that everyone refers to bandwidth as speed.
More seriously, though, the best way to explain the difference is like this (using a pipe as an example):
- Bandwidth has to do with how wide or narrow a pipe is.
- Latency has to do with the contents of the pipe; how fast it moves from one end to the next.
Latency and Bandwidth – Cause and Effect
There is a cause and effect when it comes to latency and bandwidth. In other words, one will affect how the other functions. And ultimately, the final outcome is the speed of your internet connection.
For example, if you have a real low latency, but you have a small bandwidth, it’ll take longer for information to travel from point A to point B compared to a connection that has a low latency and high bandwidth. To put this into perspective, 5 Nascar race cars will get from point A to point B faster if they’re on a 5 lane freeway (low latency, high bandwidth) compared to the same number of cars making the same trip down a 1 lane freeway (low latency, small bandwidth).
What is a Good Latency?
A good figure for latency, like bandwidth or anything internet related, is relative. What are you going to be using the internet for? That would make the question much easier to answer.
That said, anything under 100ms is reasonable. If you want to play games, especially first person shooters or driving games, then you should aim for a latency of less than 50ms and preferably less than 30ms.
What Affects Latency?
There are a number of things that affect latency:
Connection Type – The type of connection you use will affect your latency. A good example is satellite internet. Satellites are tens of thousands of miles away in space. When you make a request it goes to the satellite, to the main ISP hub and internet, and then back again. It has to make multiple trips to space and back for you to get the data you requested. This (obviously) takes a long time. As a result satellite connections have ping rates in the range of 500ms. This is very high, especially when you compare it to a solid cable connection (like mine) that has a ping rate of 12ms.
Distances – The further you are away from something (satellites, ISP hub, etc) the longer it’ll take for information to be sent from there to your computer.
Congestion – This goes hand in hand width bandwidth. The smaller your bandwidth connection (or if you share bandwidth), the more likely you’ll experience congestion (slower internet), especially with a low latency. All of this information is coming at you real quick but has to slow down because there the pipe (bandwidth) is only so big and can only fit so much in it at once. So your data has to wait it’s turn.