Today, we dive into a digital enigma – the case of the missing Internet Protocol version, IPv5, and how its story intertwines with IPv6’s current challenges.
To appreciate the IPv5 narrative, we must begin with IPv4. Introduced in 1981, IPv4 has been the backbone of the internet, providing us with 4.3 billion unique addresses (IPv4 – 123.45.67.89). But, with the internet’s explosive growth, this number proved insufficient by the late 80s【19†source】.
While many expected a sequential jump to IPv5, it never materialized in the public domain. Instead, IPv5 was the unofficial name for the Internet Stream Protocol, an experimental system for streaming voice and video. It was a pathfinder, not a fully-fledged successor to IPv4, and it included the number ‘5’ in its packet headers, hence the confusion.
| Feature | IPv4 | IPv6 | IPv5 (ST/ST2) |
|---|---|---|---|
| Address Example | 123.45.67.89 | 2001:db8::ff00:42:8329 | N/A |
| Address Space | 4.3 billion addresses | 340 undecillion addresses | N/A |
| Introduction | 1981 | Standardized in 2017, introduced in 1995 | Experiment in the 1970s-1990s |
| Primary Use | General internet connectivity | Designed to replace IPv4, but slow adoption | Experimental streaming of voice/video |
| Current Status | Still widely used, but addresses exhausted | Gradually being adopted, coexists with IPv4 | Never widely deployed |
IPv6 (e.g., 2001:db8::ff00:42:8329) emerged as the actual successor with a staggering 340 undecillion addresses, addressing the limitations of IPv4 and adding improvements in efficiency, security, and performance. It was introduced in 1995 and became a standard in 2017【18†source】【19†source】.
Despite its benefits, IPv6 adoption has been slow. Migrating to IPv6 is a significant investment, and incompatibility issues with IPv4 infrastructure persist. As of December 2021, only about 33% of Google users accessed the web using IPv6【20†source】.
IPv5, or rather the lack of it, teaches us a valuable lesson. Not all protocols make it to global implementation, but they pave the way for more advanced systems, much like IPv6, which continues to face adoption challenges but remains the best long-term solution for the internet’s growth.
Stay connected, and until next time, keep looking beyond the numbers!
Alexey Shkittin
CEO
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