Key exchange 3
Second method:
- Signed Public Master key emailed to RIPE NCC;
- Using the Master key RIPE NCC then encrypts a `secret` and emails it back to the contact address
- LIR decrypts the `secret` and confirms with RIPE NCC
Remarks:
- We trust the contact information belonging to the reg-id to be correct.
- We trust e-mail to the LIR not to be intercepted and blocked.