Security and Reliability Research of Remote Access for Subsea Blowout Preventer System

Remote access for subsea blowout preventer system based on virtual private network technology over the Internet is developed. The hardware configuration and software development for remote access are described. The redundant Ethernet networks, cryptography with smart card and firewall are used to improve the security and reliability. With respect to common cause failure, the performances of Ethernet network are evaluated by using Markov method with multiple error shock model. Due to the complexity, the system is split into a set of independent modules which are merged with Kronecker product approach. The availability and reliability are researched. The reliability analysis shows that the redundant Ethernet network equipments have safety integrity level of 4, which meets the requirement of remote access of subsea blowout preventer system. In addition, the effects of failure rate of Ethernet card on the availability and reliability are obvious, which should be paid more attention when designing the Ethernet network.