The difference between bandwidth and latency

What’s the difference between bandwidth and latency? By reading the definition of both terms above you probably already spot the difference between the two, but I’ll give you an analogy to make it easier to understand it if you are still confused. Imagine a highway with 4 lanes where the speed limit is 60 mph. Now on the Internet, bandwidth is the highway, and latency is the 60 mph speed limit. Now if you want to increase the amount of cars that travels through the highway you can add more lanes, but because the highway has too many curves, and bumps, you can’t increase the speed limit so all cars have to travel at 60 mph still. It doesn’t matter how many lanes the highway has, the cars will get to their destination at the same time regardless of the size of the  highway!

Why increasing bandwidth increases download speed then you might ask, isn’t that speed? No, by increasing bandwidth you increase capacity not speed. Following the highway analogy, imagine that vehicles traveling through that highway were all trucks with house bricks for delivery. All trucks have to travel at 60 mph, but once they arrive at their destination instead of delivering 4 loads of bricks, 6 loads are delivered because 2 more lanes were added to the highway. The same thing happens when you add bandwidth to an Internet connection, the capacity is increased but the latency (speed ) stays the same.

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