e hmac authentication prior to operation an initialization process should be performed to set the system up for operation the system should be initialized in a physically secure environment since the bmc will be transmitting keys in plain text over the i 2 c bus in an exemplary initialization process the bmc first receives a command to initialize the authentication agents included in this command is the shared secret key to be used for all communications the bmc stores this key in its non volatile storage the bmc then proceeds to write this key to the write once registers of all the attached authentication agents the bmc then validates that all the authentication agents keys have been written properly by performing at least one authenticated transaction to an i 2 c device on each bus as described above with respect to fig3 and 4 if an error is detected during the authentication the authentication agent 39 s key is cleared and reprogrammed after all the authentication agents have been verified then the system is ready for normal operation as an alternative the bmc code and authentication agents could have the secret key embedded in their designs this would eliminate the initialization procedure however care would have to be taken to make sure that the key is not recoverable from code updates using any known manner the above described steps can be implemented in hardware and or using standard well known programming techniques the novelty of the above described embodiment lies not in the specific programming techniques but in the use of the steps described to achieve the described results software programming code which embodies the present invention is typically stored in permanent.