1.1. Requirements Notation and Conventions (要件の表記と慣習)

本書のキーワード "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", "OPTIONAL" は, ここに示すとおりすべて大文字で出現する場合に限り, BCP 14 [RFC2119] [RFC8174] に記載のとおりに解釈される.