Your main attack vectors are: 1) A disgruntled employee sets up a surreptitious tap on the network to see if any secret material comes through. A high value ta

Your main attack vectors are: 1) A disgruntled employee sets up a surreptitious tap on the network to see if any secret material comes through. A high value target would be `Authorization: Bearer` in HTTP headers, but there are plenty of other things to slurp up. 2) A normally honest employee running an unrelated network tap to diagnose an issue with the SDN spots your Authorization headers (or other secrets), and knowing that they have a legitimate reason to have the wire capture, copies out the key material. This is very hard to prevent, since network admins can and should be tapping the network from time to time. I'm not particularly concerned about someone from outside Google breaking into the SDN fabric, though a hypervisor breach could leak network traffic from other tenants on your instance (if you are sharing).