Bitmessage 的设计很神奇
Bitmessage is a public key encrypted messenger with two key points of difference from most encrypted messengers: first, messages are sent using a gossip protocol (all users receive and forward all messages), and second, messages are sent without a destination address.
Traffic analysis (even by a GPA) becomes extremely difficult. It is not possible to know whether a user is receiving a message or simply flooding someone elses message, since Bitmessage clients/users relay all messages they receive even ones that they successfully decrypt.
Although all clients are routers, routers cant gain any information about the messages they relay, as messages contain only a small proof of work and no destination address.