Match each cryptographic concept with its closest analogue in the traditional postal system. Each concept has exactly one match, but some numbered items will not be used.
Cryptographic concepts:
- Public key
- Private key
- Digital signature
- Encryption
- Authentication
- Message (plaintext)
- Ciphertext
- Authentication code/tag
- Trusted third party
Postal analogues:
- Name and address displayed on a mailbox
- Postage stamp
- Checking the authenticity of a wax seal
- Placing a letter inside an opaque envelope and sealing it
- Wax seal on an envelope
- Handwritten signature inside a letter
- Letter before it is placed in an envelope
- Sealed envelope containing a letter
- Postal authority that verifies the identity of mailbox owners
- Publicly accessible slot of a locked mailbox
- Key that opens the mailbox
Post a solution as sequence of 9 numbers, like 1 3 4 5 6 9 8 7.