Using Monero keys implement the capability for users to broadcast encrypted messages to subscribers, or vendors to broadcast to multiple customers etc.
(1) Alice generates a random session key, K, and encrypts M using K.
E (M)
K(2) Alice gets Bob’s, Carol’s, and Dave’s public keys from the database.
(3) Alice encrypts K with Bob’s public key, encrypts K with Carol’s public key, and then
encrypts K with Dave’s public key.
E (K), E (K), E (K)
B C D(4) Alice broadcasts the encrypted message and all the encrypted keys to anybody who cares
to receive it.
E (K), E (K), E (K), E (M)
B C D K(5) Only Bob, Carol, and Dave can decrypt the key, K, each using his or her private key.
(6) Only Bob, Carol, and Dave can decrypt Alice’s message using K.
Using Monero keys implement the capability for users to broadcast encrypted messages to subscribers, or vendors to broadcast to multiple customers etc.
Reference:
Schneier, B. (2015). Front Matter. In Applied Cryptography, Second Edition, B. Schneier (Ed.). https://doi.org/10.1002/9781119183471.fmatter