RFC 2052:A DNS RR for specifying the location of s...
RFC-Ref

2. Introductory example

   When a SRV-cognizant web-browser wants to retrieve

      http://www.asdf.com/

   it does a lookup of

      http.tcp.www.asdf.com

   and retrieves the document from one of the servers in the reply.  The
   example zone file near the end of the memo contains answering RRs for
   this query.

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