Bandwidth and Latency
When people complain about slow internet, they might be experiencing two very different problems. Understanding the difference between bandwidth and latency helps you diagnose issues and set realistic expectations.
Bandwidth: The Width of the Pipe
Bandwidth measures how much data can flow through a connection in a given time — typically expressed in megabits per second (Mbps) or gigabits per second (Gbps).
Think of it as the width of a highway. A six-lane highway can carry more cars per hour than a two-lane road. Similarly, a 100 Mbps connection can transfer more data per second than a 10 Mbps connection.
High bandwidth matters for:
- Downloading large files
- Streaming high-definition video
- Multiple devices using the network simultaneously
Latency: The Travel Time
Latency measures how long it takes for data to travel from one point to another — typically expressed in milliseconds (ms).
Using the highway analogy, latency is how long the drive takes, regardless of how many lanes exist. A car on an empty highway still takes time to travel from point A to point B.
Low latency matters for:
- Video calls (you want responses to feel instant)
- Online gaming (actions need immediate feedback)
- Interactive applications (typing in a remote document)
They're Independent
Here's the key insight: bandwidth and latency are separate measurements. You can have:
- High bandwidth, high latency: Satellite internet often works this way — lots of data capacity, but signals travel to space and back, adding delay
- Low bandwidth, low latency: A slow but local connection might respond quickly even if it can't transfer much data
- High bandwidth, low latency: The ideal scenario — fast and responsive
- Low bandwidth, high latency: The frustrating scenario — slow and unresponsive
Diagnosing Problems
If video streams buffer but eventually play smoothly, you might have a bandwidth problem. If video calls have awkward delays but the picture is clear, latency might be the issue.
Understanding these concepts helps you communicate with internet providers, choose appropriate services, and troubleshoot effectively.