October 1997 - dns-wg - mailman.ripe.net

RE: SLD starting with digit (or containing only digits)
by zsako＠banknet.net 10 Oct '97

10 Oct '97

> From woeber(a)cc.univie.ac.at Fri Oct 10 13:51:53 1997 Thanks to all who answered me. I am still confused, because the RFCs seem to be somewhat in contradiction with each other. The RFC1912 says: (Labels were initially restricted in [RFC 1035] to start with a letter, and some older hosts still reportedly have problems with the relaxation in [RFC 1123].) Note there are some Internet hostnames which violate this rule (411.org, 1776.com). On the other hand RFC1123 says: If a dotted-decimal number can be entered without such identifying delimiters, then a full syntactic check must be made, because a segment of a host domain name is now allowed to begin with a digit and could legally be entirely numeric (see Section 6.1.2.4). However, a valid host name can never have the dotted-decimal form #.#.#.#, since at least the highest-level component label will be alphabetic. This is in my view in contradiction with the last sentence quoted by me from RFC1912... [ More than that, RFC2181, which obsolates RFC1123, basically says that the DNS should be able to handle any binary string as a domain name (with the length limitations that apply). However, it emphasizes that the applications may impose restrictions on this... I am curious when will *.com be registered? :)) ] Janos

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RE: SLD starting with digit (or containing only digits)
by Wilfried Woeber, UniVie/ACOnet 10 Oct '97

10 Oct '97

Hi Janos! >I would be grateful if someone could tell me what problems could arise >by permitting domain names starting with a digit, or even containing >*only* digits, under a TLD. You might want to refer to RFC1912: Common DNS Operational and Configuration Errors and pages 2, 3 in particular. Wilfried.

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SLD starting with digit (or containing only digits)
by zsako＠banknet.net 10 Oct '97

10 Oct '97

Dear all, I would be grateful if someone could tell me what problems could arise by permitting domain names starting with a digit, or even containing *only* digits, under a TLD. I know this is not in accordance with RFC952. My question really is what technical problems could be expected if a TLD were to decide that it allows the above (and currently the required domain name length is only two characters). Thank you for any help on this. Janos Zsako

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