registration guidelines draft 04 comments

I was surprised that there was no mention of reserved characters in 
draft-hansen-2717bis-2718bis-uri-guidelines-04.txt [1].

Since the determination of whether a character must be percent-encoded is 
partially dependent upon whether it has a reserved purpose in the URI 
component in question, shouldn't a URI scheme spec be clear about which 
reserved characters that might appear in the URI have a reserved purpose,
above & beyond that specified by the generic syntax?

For example, in April, Bruce Lilly noticed that it's insufficient for RFC 2368 
and the new mailto draft to just say 'Within mailto URLs, the characters "?", 
"=", "&" are reserved' because those characters don't always have to be 
treated specially. [2] He is right, I think, but he doesn't go far enough; the 
new draft should adhere to the new terminology: a scheme cannot say that 
characters X, Y, and Z are reserved; RFC 3986 has established the set of 
characters that are reserved and this cannot be changed. Rather, the scheme 
should clarify exactly when & where the characters designated as reserved must 
be percent-encoded. It should also make it clear, or at least implicit, how to 
interpret percent-encoded octets corresponding to those reserved characters.

For example, are these equivalent?

mailto:mailinglist-return-user=host.com@lists.otherhost.com
mailto:mailinglist-return-user%3Dhost.com@lists.otherhost.com

I think they are, but if "=" is always considered to have a reserved purpose 
no matter where it appears in a mailto URI, then they are not.

Sorry I haven't time to come up with a very carefully worded phrase to add to 
the guidelines for new URI schemes, but I hope someone can make a good 
suggestion for how schemes should refer to and make recommendations for
reserved characters.

Thanks,
Mike


[1] http://www.ietf.org/internet-drafts/draft-hansen-2717bis-2718bis-uri-guidelines-04.txt
[2] http://lists.w3.org/Archives/Public/uri/2005Apr/0002.html

Received on Tuesday, 21 June 2005 02:38:05 UTC