A Deep Space Communications Link Station was a K-class space station that served as part of Starfleet's communications grid in the 23rd century. Several such stations operated in Federation space, and at least one was in the general vicinity of the Tau Delta system in the galaxy's Beta Quadrant, not far from one of the main territorial regions of the Klingon Empire.
In 2268, Ronald Tracey coerced Harry Mudd, disguised as Captain James T. Kirk, to retrieve daily operations schedules for several nearby Starfleet outposts from the Federation starbase on Tau Delta IX, including scheduled maintenance periods for Deep Space Communications Link Stations.
Tracey then took "Kirk" to one of the stations aboard a stolen class F shuttlecraft, timed to coincide with a busy maintenance shift. After landing in the station's shuttle bay, they approached station commander Barlow on the pretext of performing a surprise inspection. While there, Tracey collected vital data to sell to Koloth as part of a planned Klingon incursion into newly claimed Federation territory. (TOS - New Visions comic: "Made Out of Mudd")