IPv5 – What happened with this protocol?

IPv5 is version 5 of the IP Protocol defined in 1979 and that did not transcend beyond the experimental field, IPv1, IPv2, and IPv3 only existed in the test and demonstration stage. IPv5 is an experimental resource reservation protocol known as the Internet Streaming Protocol (ST). The purpose is to provide quality of service compatible with multimedia services (voice \ video and data traffic in real time) and is transmitted over the Internet. It consists of two protocols: the ST protocol for data transmission and the Flow Control Message Protocol (SCMP). It is also known as ST2. This protocol was never used beyond the experimental field. The IP version of IPv6 is an alternate version of IPv4.

Both ST2 and IP apply the same addressing schemes to identify different hosts. ST2 and IP packets differ in the first four bits, which contain the version number of the inter-network protocol: number 5 is reserved for ST2. As a network layer protocol, like IP, ST2 operates independently of its underlying subnets. Existing implementations use ARP for address resolution, and use the same Layer 2 SAPs as IP.

IPv6 was supposed to be the next gen over IPv4: increased the number of bytes used in addressing from 4 bytes to 16 bytes, introduced any broadcast routing, removed the IP layer checksum, and many of other improvements. . One of the fields that remained, of course, was the version field: these 8 bits identify this IP header as version “4” when there is a 4 there, and they would presumably use a “5” to identify this next gen version. . But as we saw this they had already been given a role.

More reads:
IPv6 Protocol and how it replaces IPv4
IPv4 or Internet Protocol version 4

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