IPv3

IPv3 is the roughly the third specified version of the Internet Protocol; it never entered service. (A pity, as it had variable-length addresses, the availability of which would have avoided many headaches caused by the provision of only fixed-length addresses in IPv4.) IPv3 was also the first version in which the functionality of the Internet Protocol was formally separated from those of the 'application' (to the internet layer) layers such as TCP and UDP.

External links

• Vinton G. Cerf. Jonathan B. Postel, Specification of Internetwork Transmission Control Program - TCP Version 3 - IPv3 is given in section 4.3.1, 'Internetwork Packet Format' (starting on pg. 61 of the PDF)