## page was renamed from DNS/1/RFC/1123
## page was renamed from DNS/基礎知識/RFC/1123
## page was renamed from DNS/RFC/1123
## page was renamed from DNS/RFC1123
= DNS/RFC/1123 =
DNS関連は第６章です。

https://datatracker.ietf.org/doc/html/rfc1123

https://jprs.jp/tech/material/rfc/RFC1123-ja.txt (JPRS訳)

http://www2s.biglobe.ne.jp/~hig/tcpip/HostReq_Appl.html
 訳のおかしいところもあるので、どうするかは検討中。

== full resolver ==
リゾルバは、個々の要求に対するリモートアクセスの繰り返しを避けるために、
ローカルなキャッシング機能を実装しなければならず (MUST)、
キャッシュ内の情報をタイムアウトしなければならない (MUST)。

== stub resolver ==
接続されたネットワーク上の再帰ネームサーバや "近くの" ネットワークのサービスに頼る。

要求を冗長なネームサーバに向けることができなければならない (MUST)

== host name ==
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.

Host software MUST handle host names of up to 63 characters and
      SHOULD handle host names of up to 255 characters.

Whenever a user inputs the identity of an Internet host, it SHOULD
      be possible to enter either (1) a host domain name or (2) an IP
      address in dotted-decimal ("#.#.#.#") form.  The host SHOULD check
      the string syntactically for a dotted-decimal number before
      looking it up in the Domain Name System.


   6.1 DOMAIN NAME TRANSLATION

      6.1.1 INTRODUCTION