[BCP34]    Best Current Practice 34,
              <https://www.rfc-editor.org/info/bcp34>.
              At the time of writing, this BCP comprises the following:

              Senie, D., "Changing the Default for Directed Broadcasts
              in Routers", BCP 34, RFC 2644, DOI 10.17487/RFC2644,
              August 1999, <https://www.rfc-editor.org/info/rfc2644>.