CSA Preface Standards development within the Information Technology sector is harmonized with international standards development. Through the CSA Technical Committee on Information Technology (TCIT), Canadians serve as the SCC Mirror Committee (SMC) on ISO/IEC Joint Technical Committee 1 on Information Technology (ISO/IEC JTC1) for the Standards Council of Canada (SCC), the ISO member body for Canada and sponsor of the Canadian National Committee of the IEC. Also, as a member of the International Telecommunication Union (ITU), Canada participates in the International Telegraph and Telephone Consultative Committee (ITU-T). For brevity, this Standard will be referred to as \"CAN/CSA-ISO/IEC 11770-4\" throughout. This Standard supersedes CAN/CSA-ISO/IEC 11770-4:07 (adopted ISO/IEC 11770-4:2006). At the time of publication, ISO/IEC 11770-4:2017 is available from ISO and IEC in English only. CSA Group will publish the French version when it becomes available from ISO and IEC. Scope This document defines key establishment mechanisms based on weak secrets, i.e. secrets that can be readily memorized by a human, and hence, secrets that will be chosen from a relatively small set of possibilities. It specifies cryptographic techniques specifically designed to establish one or more secret keys based on a weak secret derived from a memorized password, while preventing offline brute-force attacks associated with the weak secret. This document is not applicable to the following aspects of key management: — life-cycle management of weak secrets, strong secrets, and established secret keys; — mechanisms to store, archive, delete, destroy, etc. weak secrets, strong secrets, and established secret keys.