In article <[EMAIL PROTECTED]>, Mark Andrews <[EMAIL PROTECTED]> wrote:
> Labels start with a letter or digit. Labels end with a > letter or digit. Letter, digit or hypen in the middle of > the label. > > All labels meet the above with the exception of a mbox where > second to last labels meet the above. > > A single period can also be used as a place marker. > > The rules are applied to the owner names of A, AAAA and > MX records. > NS and MX records rdata. > IN-ADDR.ARPA and IP6.ARPA PTR records rdata. > (I don't think I've missed any cases). > > Underscore was choosen for SRV records so that they would > *not* clash with hostnames. Even folks who put underscores in hostnames are practically never going to clash with SRV records. Labels in SRV records *start* with underscores, and no one does that with hostnames, even if their nameservers allow it. Underscores, like hyphens in standard-conforming hostnames, are always used as word separators in hostnames. -- Barry Margolin, [EMAIL PROTECTED] Arlington, MA *** PLEASE don't copy me on replies, I'll read them in the group ***
