blockchain_protocol_package.txt

 0                   1                   2                   3   
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                MagicNo (blockchain identifier)                |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|C|Pay-|Chec|         Payload of dynamic length, e.g.           |
|M|load|ksum|     block, transaction or primitive value         |
|D|Size|    |                                                   |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

MagicNo     : 32 Byte length : Uniquely identifies the blockchain
                               to which this package belongs.
CMD         :  1 Byte length : Command flag that indicates the
                               purpose of this message.
Payload Size:  4 Byte length : The size of the payload in bytes. 
Checksum    :  4 Byte length : The first 4 bytes of the payload
                               hash. (TODO: Specify hashing
                               algorithm)

Command Specification (CMD field)

VERSION           0x00 Initiates the handshake, first package
                       send to a new node
VERSION_ACK       0x01 Response to the VERSION package and
                       finalizes the handshake
REQUEST_BLOCK     0x02 Periodical message to request a new block
BLOCK             0x04 Response to REQUEST_BLOCK request 
TRX               0x08 Propagation of transaction
CONFIRM_TRX       0x10 Confirmation of a received transaction
GET_PEERS         0x20 Request all known nodes, related to a 
                       specific blockchain
PEERS             0x40 Response to the GET_PEERS request with
                       a list of known nodes.