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Re: Underscore in Host names
>
> ----- Transcript of session follows -----
> ... while talking to yukon.cren.org.:
> >>> MAIL From:<descombes@ima_vms.enst.fr>
> <<< 501- ^
> <<< 501 Path data: Extra garbage before terminating ">"
> 554 <listproc@yukon.cren.org>... Remote protocol error
>
> ----- Message header follows -----
>
> Underscore is legal, Zmailer 2.9.3-940816 is rejecting them ????
>
Not quite.
Although it is acceptable for RFC-822 but it is NOT acceptable
for Internet host according to RFC-952 and RFC-1123.
Host/domain names can consist of: letters, digits and hyphen.
Thats all.
Here is a fragment of the grammar [RFC-952]:
<name> ::= <let>[*[<let-or-digit-or-hyphen>]<let-or-digit>]
RFC-1123 states it this way:
2.1 Host Names and Numbers
The syntax of a legal Internet host name was specified in RFC-952
[DNS:4]. One aspect of host name syntax is hereby changed: the
restriction on the first character is relaxed to allow either a
letter or a digit. Host software MUST support this more liberal
syntax.
Jurek
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Jerzy Sobczyk ____________ ___ Institute of Control and
J.Sobczyk@ia.pw.edu.pl / / | |/ _\ Computation Engineering,
tel.+48 2 6210070 / / /| | | (____ Warsaw University
ext.7297 / / _>| | |\____ \ of Technology
fax.+48 22 253719 /__/__/__|__|__|_____) \ Nowowiejska 15/19
tlx. 813 307 pw pl /________________________/ 00-665 Warsaw, POLAND
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