If you have secrets to keep, and your adversaries have that kind of access, better a DDOS than a leak.
Edit:
This kind of observation would already require physical access to the communications medium (e.g. a fiber optic cable). So if you could DoS a quantum encrypted channel by measuring it, you could equally well DoS a classical channel by just cutting the fiber.
The comment just above mine, which does a better job than me of explaining the degree of access required.
Besides which, it’s not as though you can only use this. You try your quantum channel first, and if it’s down you know you’re under attack, and act accordingly with your Classical backups.
Edit: This kind of observation would already require physical access to the communications medium (e.g. a fiber optic cable). So if you could DoS a quantum encrypted channel by measuring it, you could equally well DoS a classical channel by just cutting the fiber.
The comment just above mine, which does a better job than me of explaining the degree of access required.
Besides which, it’s not as though you can only use this. You try your quantum channel first, and if it’s down you know you’re under attack, and act accordingly with your Classical backups.