The keywords “MUST”, “MUST NOT”, “REQUIRED”, “SHALL”, “SHALL NOT”, “SHOULD”, “SHOULD NOT”, “RECOMMENDED”, “NOT RECOMMENDED”, “MAY”, and “OPTIONAL” in the specification are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.
An implementation of the specification is not compliant if it fails to satisfy one or more of the “MUST”, “MUST NOT”, “REQUIRED”, “SHALL”, or “SHALL NOT” requirements defined in the specification. Conversely, an implementation of the specification is compliant if it satisfies all the “MUST”, “MUST NOT”, “REQUIRED”, “SHALL”, and “SHALL NOT” requirements defined in the specification.
The specification uses a set of conventions to describe the structure of
strings. Terms surrounded by < and > are placeholders for the actual value.
For example, <name> is a placeholder for the actual name of the column. Terms
surrounded by [ and ] are optional. For example, <[name]> means that the
name is optional.