Interstellar Communication and Quantum Key Distribution on a Protected Ground Node

Maintaining secure key distribution, and protected local node state, across an intermittent or disrupted long-distance link is the problem addressed here. A deep-space path is the extreme case. Dust, distance, and loss of the carrier do not by themselves preserve that state, distribute a key, or protect the ground system that holds the key register. The March 2025 communications file raised deep-space relays as a subject. A baryonic radio or laser terminal is not the regulator of the deposited layer partition. Frequency-bin entanglement supplies the key on a channel that can break and resume. The proposed ground architecture uses a haloscope mesh to intercept and dissipate an in-band microwave disturbance before it can couple into the key register or the clock. The node keeps its own state through the outage. The monitor may read telemetry and may not write protected state. Write-back remains W = 0, as an architectural constraint and not as a consequence of operator commutation. No new link, key protocol, or industry is claimed.