TL;DR: DARPA's quantum network was one of the world's first operational quantum networks, running in the Boston metropolitan area since 2004. It has tested multiple QKD protocols and hardware from different
DARPA's quantum network was one of the world's first operational quantum networks, running in the Boston metropolitan area since 2004. It has tested multiple QKD protocols and hardware from different vendors. The network continues to serve as a testbed for quantum networking research and interoperability testing.
Type
Government quantum network testbed
Protocol
Multiple QKD and entanglement protocols
Range
Boston metropolitan area
Status
Operational; one of the first quantum networks (2004-present)