Reserved for future expansion or special protocol functions. Slave ID vs. Register Address
This paper proposes a "Security Enhancement Protocol" that uses digital signatures (private keys) and symmetric encryption (shared keys) to prevent data tampering and unauthorized commands. modbus slave key
A thesis from Georgia Tech describes a version of Modbus that prevents "replay attacks" by requiring the master to generate a new secret key with the slave before a counter wraps. Reserved for future expansion or special protocol functions
identity = ModbusDeviceIdentification() identity.VendorName = 'Modbus Slave Example' identity.ProductCode = 'PYM' identity.VendorUrl = 'https://github.com/pymodbus-dev/pymodbus' identity.ProductName = 'PyModbus Slave' identity.ModelName = 'PyModbus Slave' identity.MajorMinorRevision = '1.0' modbus slave key
context = ModbusServerContext(slaves=store, single=True)
from pymodbus.server import StartTcpServer from pymodbus.device import ModbusDeviceIdentification from pymodbus.datastore import ModbusSlaveContext, ModbusServerContext from pymodbus.datastore import ModbusSequentialDataBlock