Subject: [Simple] mapping im: and pres: URIs

From: Peter Saint-Andre <[email-masked]>
Date: Mon, 16 Apr 2007 16:56:54 -0600

In draft-saintandre-xmpp-simple-09, we define mappings of sip:, sips:, 
pres:, and im: URIs to XMPP addresses and vice-versa. Unfortunately I am 
confused about exactly which characters are reserved, unreserved, and 
forbidden (i.e., to-be-escaped) for the relevant addressing schemes. In 
this mail I ask about im: and pres: URIs (I still need to research 
sip/sips URIs further before posting).

RFC 3859 defines the syntax of the pres: URI scheme as follows (the im: 
URI scheme is defined equivalently in RFC 3860):

    The syntax follows the existing mailto: URI syntax specified in RFC
    2368.  The ABNF is:

    PRES-URI         = "pres:" [ to ] [ headers ]
    to             =  mailbox
    headers        =  "?" header *( "&" header )
    header         =  hname "=" hvalue
    hname          =  *uric
    hvalue         =  *uric

    Here the symbol "mailbox" represents an encoded mailbox name as
    defined in RFC 2822 [3], and the symbol "uric" denotes any character
    that is valid in a URL (defined in RFC 2396 [10]).

A few questions:

1. What does it mean to follow the syntax of the mailto scheme from RFC 
2368 but specify that the "mailbox" rule follows RFC 2822 rather than 
RFC 822 (to which RFC 2368 refers)?

2. What does the term "encoded mailbox name" mean? (As far as I can see, 
it is not defined in RFC 2822.) Does this mean a mailbox as specified 
according to RFC 2822 but encoded according to the rules in RFC 2368 
(e.g., percent-encoding reserved characters such as "%", "&", "=", and 
"?" from RFC 2368)?

3. Was it really intended for pres: and im: URIs to completely track the 
mailbox format (from 822 or 2822), so that things like the following are 
URIs of good standing?

    pres:%20Juliet%20Capulet%20<[email-masked]>

4. In draft-saintandre-xmpp-simple-09 we make the simplifying assumption 
that we are interested in mapping local-part addresses only (leaving 
domain mapping out of scope), so that in the previous address would be 
interested in mapping "juliet" only (since domains are what they are and 
the phrase is immaterial to address mapping for routing purposes); do 
folks on this list think that is reasonable?

Thanks!

Peter

-- 
Peter Saint-Andre
XMPP Standards Foundation
http://www.xmpp.org/xsf/people/stpeter.shtml

_______________________________________________
Simple mailing list
[email-masked]
https://www1.ietf.org/mailman/listinfo/simple