RFC 1149, "Protocol for IP over Avian Carriers", has been
proven in the field. See the news at:
http://www.blug.linux.no/rfc1149/
For RFC 1149 itself, see either the original at:
http://www.faqs.org/rfcs/rfc1149.html
or the amendment, RFC 2549, at:
http://www.faqs.org/rfcs/rfc2549.html
RFC 2321 "RITA -- The Reliable Internetwork Troubleshooting Agent"
also may deserve review...