This part of IEC 62351 specifies procedures, protocol extensions, and algorithms to facilitate securing ISO 9506 – Manufacturing Message Specification (MMS) based applications. It is intended that this technical specification be referenced as a normative part of other IEC TC 57 standards that have the need for using MMS in a secure manner.This technical specification represents a set of mandatory and optional security specifications to be implemented for applications when using ISO/IEC 9506 (Manufacturing Automation Specification).NOTE Within the scope of IEC TC 57, there are two identified standards that may be impacted: IEC 61850-8-1 and IEC 60870-6.This