> I note the IETF last call was issued for rev. 2. That > revision no longer exists, hence I reviewed rev. 3. > > This document specification of a "User Principal Name", > I believe, is inadequate. > > The I-D indicates that a user_principal_name is a sequence of > 0 to 65535 bytes in the form of user@domain. However, > such a form implies the value is a character string, > but there is no mention of what character set/encoding > is used here. I would think interoperability > requires both client and server to have a common > understand of what character set/encoding is to > be used. Additionally, there is no discussion > of UPN matching. Are byte sequences that differ > only due to use of different Unicode normalizations > to be consider the same or differ? Are values > case sensitive or not? etc.. > > The domain_name field suffers not only from the > above problem, but is flawed due to use of the > outdated "preferred name syntax" of RFC 1034. > This syntax doesn't allow domains such as > 123.example. The text should likely reference > the RFC 1123 which updates the "preferred name > syntax" for naming hosts. Could the IESG / RFC editor please reject any request to publish a document which use the '"preferred name syntax" of RFC 1034'. RFC 952 as modified by RFC 1123 which was the the intent of this section of RFC 1034. For mail domains it was RFC 821 as modified by RFC 1123 (even though RFC 1123 fails to mention RFC 821). If it didn't apply you could send mail to the address records for 3com.com but not to the MX records and I don't think that was ever the intent. Domain name, hostname and mail domain are not interchangable concepts. There are too many RFCs which incorrectly interchange these concepts which leads to lots of confusion. The latter to are very restriced subsets* of the first. > Additionally, no mention of how International > domain names (IDNs) are to be handled. If we restrict to RFC 952 as modified by RFC 1123 then IDN comes into play. That doesn't help with the user side however unless we apply the mailbox translation for the DNS. > I recommend ABNF be used to detail the syntax > of each of these fields and that the I-D detail > how values of these fields are to be compared. > Additionally, the I-D should discuss how IDNs > are to be handled. > -- Kurt * Hostnames that are 254 and 255 characters long cannot be expressed in the DNS. -- Mark Andrews, ISC 1 Seymour St., Dundas Valley, NSW 2117, Australia PHONE: +61 2 9871 4742 INTERNET: Mark_Andrews@xxxxxxx _______________________________________________ Ietf@xxxxxxxx https://www1.ietf.org/mailman/listinfo/ietf