2. Requirements Language

この節では optimistic HTTP/1.1 protocol transitions の RFC 原文を保持し, request smuggling risks, parser exploit risks, existing Upgrade tokens, HTTP CONNECT requirements, IANA status を含めます.

2.  Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in
   BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.