Charles Lindsey wrote:
In <41541BE8(_dot_)7030702(_at_)erols(_dot_)com> Bruce Lilly
<blilly(_at_)erols(_dot_)com> writes:
Temporarily leaving aside "strip these angle brackets", there
are several issues that should be taken into consideration
when comparing identifiers:
* domain names are case-insensitive, so
"<1234(_at_)foo(_dot_)example(_dot_)net>"
is semantically identical to "<1234(_at_)FoO(_dot_)ExAmPlE(_dot_)nEt>". RFC
2822 presents a problem here, because a receiver can never
be sure whether or not an RFC 2822 id-right is a case-
insensitive domain name or something else (which might be
case-sensitive).
No, I don't think that is right. An id-right, as defined by RFC 2822[...]
You have missed the critically important fact that in all cases
discussed, the relevant RFCs refer to RFC 822 (a full Standard),
not RFC 2822 (a Proposed Standard). And RFC 822 defines the
identifiers in question as containing a local-part and a domain.
RFC 2822 id-right is a problem because it changes the semantics.
* local-parts and domain literals need to be canonicalized
w.r.t. quoting conventions prior to comparisons. The
following are all semantically identical:
<foo(_dot_)bar(_at_)[1(_dot_)2(_dot_)3(_dot_)4]> (canonical form)
<"foo.bar"@[1\.2.3.4]>
<"f\oo.bar"@[1\.2.3.4]>
<"f\oo\.bar"@[1\.2.3.4]>
<"f\oo\.bar"@[1\.\2.3.4]>
Yes, that is indeed true within Email, but it is not true (and cannot be
true) within Netnews.
Content-ID is a MIME production which applies wherever MIME
is used. The start parameter refers to a content identifier,
as does the cid URI scheme. Whether they are used in "mail"
messages or "news" messages or even in unrelated formats and
protocols such as HTTP, the syntax and semantics are those
assigned by the MIME RFCs, whether you like it or not.