Interstellar relay
An interstellar relay was a type of communication relay station operated by Starfleet Communications in the mid-23rd century.

During the 2250s, Starfleet had an exemplary reputation for tech hygiene, as evidenced by it consistently sending a ship to fix any relay that went down. In 2256, the  was sent to investigate damage to an interstellar relay located in a binary star system at the edge of Federation space. It was eventually found that the Klingons had damaged the relay to lure in Starfleet. ()

There were interstellar relays orbiting Earth. ()

Communications technology
Space stations
Subspace