List of IP version numbers
Packets that hold Internet Protocol data carry a 4-bit IP version number as the first field of its header.REFERENCE FOR RFC791 IS NOT DEFINED YET. You are invited to add it here.'REFERENCE FOR RFC8200 IS NOT DEFINED YET. You are invited to add it here. Currently, only IPv4 and IPv6 packets are seen on the Internet, having IP version numbers 4 and 6, respectively.
IP version numbers
As the version number is carried in a 4-bit field, only numbers 0–15 can be assigned.
| IP version | Description | Status |
|---|---|---|
| 0 | Internet Protocol, pre-v4 | Reserved.[1] |
| 1–3 | Unassigned. | |
| 4 | Internet Protocol version 4 (IPv4)REFERENCE FOR RFC791 IS NOT DEFINED YET. You are invited to add it here. | Active. |
| 5 | Internet Stream Protocol or ST | Obsolete; superseded by ST-II. |
| 5 | Internet Stream Protocol or ST-IIREFERENCE FOR RFC1819 IS NOT DEFINED YET. You are invited to add it here. | Obsolete. |
| 6 | Simple Internet Protocol (SIP) | Obsolete; merged into IPv6 in 1995.[1] |
| 6 | Internet Protocol version 6 (IPv6)REFERENCE FOR RFC8200 IS NOT DEFINED YET. You are invited to add it here. | Active. |
| 7 | TP/IX The Next Internet (IPv7)REFERENCE FOR RFC1475 IS NOT DEFINED YET. You are invited to add it here. | Obsolete.REFERENCE FOR RFC6814 IS NOT DEFINED YET. You are invited to add it here. |
| 8 | P Internet Protocol (PIP)REFERENCE FOR RFC1621 IS NOT DEFINED YET. You are invited to add it here. | Obsolete; merged into SIP in 1993. |
| 9 | TCP and UDP over Bigger Addresses (TUBA) | Obsolete.REFERENCE FOR RFC1347 IS NOT DEFINED YET. You are invited to add it here. |
| 9 | IPv9 | April fools' day joke.REFERENCE FOR RFC1606 IS NOT DEFINED YET. You are invited to add it here. |
| 9 | Chinese IPv9 | Abandoned. |
| 10–14 | Unassigned. | |
| 15 | Version field sentinel value | Reserved. |
History
During the development of the first version of the Internet Protocol in the 1970s, the initial experimental versions 1 to 3 were not standardized. The first working version that was widely deployed was assigned version number 4.REFERENCE FOR RFC760 IS NOT DEFINED YET. You are invited to add it here.
A separate protocol based on reliable connections was developed and assigned version 5.
IP version 7 was chosen in 1988 by R. Ullmann as the next IP version because he incorrectly assumed that version 6 was in use for ST-II. However, ST-II had reused version 5 of the original ST protocol.REFERENCE FOR RFC1475 IS NOT DEFINED YET. You are invited to add it here.
In the early 1990s, when it became apparent that IPv4 could not sustain routing in a growing Internet, several new Internet Protocols were proposed. The Internet Protocol that finally emerged was assigned version number 6, being the lowest free number greater than 4.
The PIP protocol and TUBA protocol used versions 8 and 9, following version 7 for TP/IX.
In 2004, an IPv9 protocol was developed in China using 256-bit addresses.
References
- ↑ 1.0 1.1 Jeff Doyle; Jennifer Carroll (2006). Routing TCP/IP. 1 (2 ed.). Cisco Press. p. 8. ISBN 978-1-58705-202-6.
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