Why IPv5 was never used?

Question

Just wondering why IPv5 was never used? It's based on ST-II right? A QoS extension for IPv4 if I'm not taking it 100% wrong.

Does it have to do with the comparison with RSVP protocol too?

Answer 1

From what ever happened to ipv5:

In the late 1970’s, a protocol named ST — The Internet Stream Protocol — was created for the experimental transmission of voice, video, and distributed simulation. Two decades later, this protocol was revised to become ST2 and started to get implemented into commercial projects by groups like IBM, NeXT, Apple, and Sun. Wow did it differ a lot. ST and ST+ offered connections, instead of its connection-less IPv4 counterpart. It also guaranteed QoS. ST and ST+, were already given that magical “5″. And now as the Internet clock ticks, our PCs don’t use IPv5. So we’re moving onto 6.