The most important module in this security solution is the Security Module, which contains the implementation of functionalities to sign and verify an SSON certificate in a digital signature message as proxy credentials. In this module, the messages for requesting and distributing a proxy credential as well as the three-way handshake messages between the master node and the slave nodes are encapsulated as specified protocols, which are implemented as serializable objects. In this way, the messages between the communication parties can be easily managed without taking care of the packet loss in the network.