A critical analysis of open protocol for subsea production controls system communication

摘要

Production control system communication protocols used in subsea fields are primarily proprietary to the subsea vendor. Due to the proprietary nature of this communication system, the operators encounter many challenges including obsolescence management, knowledge management and conformity assessment. This paper presents an investigation of the option of using open standard protocols for subsea production control communication system. The features, functionality and standardization of existing communication protocols used in subsea control system are analyzed and compared with open standard protocols such as DNP3 (Distributed Network Protocol) and IEC60870-5-101 and their variants used with Transmission Control Protocol/Internet Protocol (TCP/IP). The features of open standard protocols were also analyzed along with the possibility of its use in subsea production control system communication. The analysis showed that the open standard protocol DNP3 and DNP3 over TCP/IP could provide significant advantages over proprietary protocols as the specifications of DNP3 are publicly available and controlled by non-profit user group. DNP3 supports unsolicited response messages, time stamping, peer-to-peer communication and its implementation can be verified by external bodies. Furthermore, DNP3 allows the operator to integrate multiple vendors' products on a single subsea network and allows the integration of slower network with faster network without losing the data throughput.