scope:

This part of IEC 62351 defines the application profile (A-profile) secure communication mechanism specifying messages, procedures and algorithms for securing the operation of all protocols based on or derived from IEC 60870-5, Telecontrol Equipment and Systems - Transmission Protocols.

The initial audience for this document is intended to be the members of the working groups developing the protocols listed in Table 1.

For the measures described in this document to take effect, they must be accepted and referenced by the specifications for the protocols themselves. This document is written to enable that process. The working groups in charge of taking this document to the specific protocols listed in Table 1 may choose not to do so.

The subsequent audience for this document is intended to be the developers of products that implement these protocols.

Portions of this document may also be of use to managers and executives in order to understand the purpose and requirements of the work.

This document is organized working from the general to the specific, as follows:

• Clauses 2 through 4 provide background terms, definitions, and references.

• Clause 5 describes the problems this specification is intended to address.

• Clause 6 describes the mechanism generically without reference to a specific protocol.

• Clauses 7 and 8 describe the mechanism more precisely and are the primary normative part of this specification.

• Clause 9 define the interoperability requirements for this secure communication mechanism, including the relationship of this standard to IEC 62351-3 for transport layer security..

• Clause 10 describes the requirements for other standards referencing this document.

The actions of an organization in response to events and error conditions described in this document are expected to be defined by the organization's security policy and they are beyond the scope of this document.