ISO (the International Organisation for Standardisation) and IEC (the International Electrotechnical Commission) form the specialised system for worldwide standardisation. National bodies that are members of ISO or IEC participate in the development of International Standards through technical committees established by the respective organisation to deal with particular fields of technical activity. In the field of information technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.

In todays modern world, most organisations have their information systems connected by networks either within the organisation, between different organisations or between the organisation and the general public. The purpose of this International Standard is to provide detailed guidance on the security aspects of the management, operation and use of information system networks, and their inter-connections. 

This part of ISO/IEC 27033 provides an overview of network security. It defines and describes the concepts associated with, and provides management guidance on, network security. It also defines how to identify and analyse network security risks and then define network security requirements. It also introduces how to achieve good quality technical security architectures, and the risk, design and control aspects associated with typical network scenarios and network technology areas.