2. 要求语言 (Requirements Language)
本文档中的关键词 "MUST"、"MUST NOT"、"REQUIRED"、"SHALL"、"SHALL NOT"、"SHOULD"、"SHOULD NOT"、"RECOMMENDED"、"NOT RECOMMENDED"、"MAY" 和 "OPTIONAL", 当且仅当它们以此处所示的全大写形式出现时, 应按 BCP 14 [RFC2119] [RFC8174] 中的说明解释.
参考文献
- [RFC2119]: Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997
- [RFC8174]: Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017