ABNF
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... Uniform Resource Identifier in
its absolute form according to the 'absoluteURI' production in the
Collected ABNF found in RFC2396(-> 3986std66) [4].
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As specified in the ABNF found in Section 2.4.2, an 'enumservice' is
made up of 'types' and 'subtypes'. For any given 'type', the
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... Enumservice is made up of a type and a type-
dependent subtype, it is sufficient to require that the 'type' itself
be unique. The 'type' MUST be unique, conform to the ABNF specified
in Section 2.4.2, and MUST NOT start with the facet "X-" which is
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The subtype, being dependent on the type, MUST be unique within a
given 'type'. It must conform to the ABNF specified in Section
2.4.2, and MUST NOT start with the facet "X-" which is reserved for
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