Definition
A permanent virtual circuit is a fixed, pre-defined data communication path established between two endpoints across a shared network. It behaves like a dedicated line for the user, but the underlying network resources are shared with other traffic. The path stays in place at all times, so data can flow whenever needed without setting up a new connection.
Plain English
A reserved 'always-on' data link between two points on a shared network. It looks and acts like a private wire, but it's really a permanent route through equipment that handles other traffic too.
Context Anchor
Seen in aviation acronym lists and in discussions of digital communication systems that move information between aircraft, ground systems, or support equipment.
Derivation
Permanent means it stays in place rather than being set up each time it's used. Virtual means it acts like a dedicated circuit even though no physical wire is reserved just for it. Circuit comes from the idea of a complete path that data travels along. Together: a path that is always available and behaves like a private line, but is actually shared.
Why Pilots Care
A pilot usually does not manage a PVC directly, but knowing the term helps when reading about communication systems that rely on pre-set digital paths to move flight or system information reliably.
Analogy
Think of a carpool lane that's always reserved for two specific commuters. The road is shared with everyone else, but their lane is permanently set aside, so they never wait to get on.
Intuition Check
Do not read permanent virtual circuit as a separate physical wire that is permanently installed just for one user. Here it means a prearranged data path that behaves like a dedicated connection inside a shared network.
Example Sentence 1
The weather data from the regional office reaches the flight service station over a permanent virtual circuit, so updates arrive continuously without dialing in.
Example Sentence 2
Network logs showed the PVC remained active throughout the flight without reconnection.