@startuml
Client1 -> Server: Send Message (PubKeyClient2 +  Payload)
Server -> Client1: Ack Message (Server UUID +  DateReceived)
Client1 --> Server: Message delivery ? (PubKeyClient2 +  Payload)
Server --> Client1: Message delivered (Server UUID +  DateReceived)

Client2 -> Server: Get Messages (PubKeyClient2)
Server -> Client2: Get Messages [](PubKeyClient2 + Payload)
Client2 --> Server: Ack Messages Processed
@enduml