1. The formula for computing iterations is simplified, so that only one division is necessary, and inverting the (1-x) into just x.
2. There are new timestamp rules. A block N must have a greater timestamp than block N-1. Also, a block's timestamp cannot be more than 5 minutes in the future.
3. A List[Tuple[uint16, str]] is added to the handshake. These are the capabilities that the node supports, to add new features to the protocol.
4. The message_id is now before the data in each message.
Richard Kiss
Mariano Sorgente
Gene Hoffman