Glossary of terms

Latency is the reaction speed of a network connection — the time it takes to send data and receive a reply — measured in milliseconds (ms). If this is too high, the resulting "lag" can be a problem for activities that rely on rapid communication, such as online gaming. This is not something most of us need to worry about as any fixed-line home broadband service will, on average, have very low latency. But a satellite broadband connection will have a very high latency due to the time it takes to transfer data to and from orbit