2. 要求语言
本文档中的关键词 "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY" 和 "OPTIONAL" 按 BCP 14 [RFC2119] [RFC8174] 中的描述解释, 但仅当它们如这里所示以全部大写形式出现时才如此.
本文档中的关键词 "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY" 和 "OPTIONAL" 按 BCP 14 [RFC2119] [RFC8174] 中的描述解释, 但仅当它们如这里所示以全部大写形式出现时才如此.