How does one reliably track down all of the defined RFC [2]822
headers? That is, when proposing a new header, how is one to be sure that
it is not already defined somewhere?
From the RFC index:
0822 Standard for the format of ARPA Internet text messages. D.
Crocker. Aug-13-1982. (Format: TXT=109200 bytes) (Obsoletes RFC0733)
(Obsoleted by RFC2822) (Updated by RFC1123, RFC1138, RFC1148,
RFC1327, RFC2156) (Also STD0011) (Status: STANDARD)
and
2822 Internet Message Format. P. Resnick, Editor. April 2001. (Format:
TXT=110695 bytes) (Obsoletes RFC0822) (Status: PROPOSED STANDARD)
Apart from the RFC822 "updated by" references to MIXER, there is no
indication here that MIME adds a new set of header names that occupy (part
of) the same naming scope as RFC [2]822 headers. Also, there are numerous
other documents that define additional headers that may appear in an
Internet message.
The usual IETF way to deal with these situations is to have an IANA
registry of values. But none exists for message headers (I can find no
reference to RFC822 or email messages in
http://www.iana.org/numbers.htm). The nearest to a registry we have seems
to be Jacob Palme's RFC 2076 and more recent Internet Draft updates
(currently draft-palme-mailext-headers-05.txt).
I would like to suggest taking Jacob's draft, and:
(a) adding an IANA considerations section to create a message header
registry (or creating a new companion document)
(b) incorporating all of the standards-track-defined headers noted in
Jacob's draft into the registry
(c) issuing the result as BCP RFC(s)
(d) noting in the RFC index that the document updates RFC 2822.
Before taking on any drafting work, I'd like to gauge the sense of whether
this general approach is likely to fly.
------------
Graham Klyne
(GK(_at_)ACM(_dot_)ORG)