Terran Neutral Zone

In the mirror universe, the Terran Neutral Zone was a ten-lightyear-wide zone around the Galactic Commonwealth. It was established in 2377 by the Tripartite Armistice and open to expansion to the Commonwealth. 

History
In the armistice signed between the then-Terran Protectorate, the $𝜇$ and the $𝜇$ in 2377, more than two dozen worlds were formally ceded to the Commonwealth in a 20 lightyear zone around Sol. The entire territory was surrounded by the Terran Neutral Zone. The Commonwealth was intend on peaceful expansion by voluntary admission of worlds. The territory shared borders with the Klingon Empire, Cardassian Union, $𝜇$ and the Taurus Pact.

In Januaray 2379, Memory Omega detonated a Genesis Device on Rhenvara V, a planet just outside the TNZ and inside Commonwealth territory, to dissuade neighboring powers from attacking.

In July 2379, the free starship Enterprise was ordered to conduct a six-week patrol of the Terran Neutral Zone.