Message originator can be identified

[fed-franz]

Description
Since broadcast messages include a maximum height, nodes receiving a message during the first relay know that the sender created the message.

Expected behaviour
When receiving a message, nodes should not be able to determine if the sender is its originator or simply a relayer.
In particular,

Possible solutions

• Seppia trick: when receiving a message with height=MAX, this is relayed with the same height to at least another peer.
• Dandelion style solution: use an "anonymity phase" in which the message is relayed linearly through a path of nodes, using an initial height chosen at random, but bigger than MAX. At each step, the node probabilistically decides whether to continue the anonymity phase or to switch to the standard behavior.