[ih] Tell me about host names and 3com

[John Levine]

The domain in an e-mail addresss after the @ sign has to be a
hostname. RFC 1035 says that a hostname contains letters, digits, and
hyphens, with the first character being a letter.

RFC 1035 was published in November 1987, but 3com.com was registered
in December 1986. It is my vague recollection that the initial letter
rule was inherited from HOSTS.TXT, but since everyone knew Bob
Metcalfe, they said, oh, all right, a leading digit is OK so long as
it's not all digits.

Does anyone remember the details? RFC1035 is still the official
standard for hostnames, and the initial letter rule has been wrong for
a long time.

R's,
John

PS: This came up as we are finally trying to update RFCs 5321 and 5322
to match reality.