> Why are we stuck with nat in 2022 again? Why did we not map the 32 bits of ipv4 to ipv6?
Oh, you mean like this:
> Addresses in this group consist of an 80-bit prefix of zeros, the next 16 bits are ones, and the remaining, least-significant 32 bits contain the IPv4 address. For example, ::ffff:192.0.2.128 represents the IPv4 address 192.0.2.128. A previous format, called "IPv4-compatible IPv6 address", was ::192.0.2.128; however, this method is deprecated.[61]
You still need to upgrade bit of networking kit between the source and destination to understand "IPv4+", and this (lack of) upgrading and enabling is what is hampering deployment.
What makes you think that companies would have been willing to make the effort to deploy "IPv4+" any more than IPv6?
> Because it is a mess. Stop denying that. If ipv6 was designed to be easily deployed via backwards compatibility then we would be using ipv6 already.
Backwards compatibile IPv6 was impossible.
IPv4 has 32 bits of address. Anything after IPv4 needed >32 bits of address. How do you fit in >32b in a data structure that is 32b? You cannot.
So you have to go an replace every bit of networking code out there to change the data structures. You know, like was done to deploy IPv6.
Oh, you mean like this:
> Addresses in this group consist of an 80-bit prefix of zeros, the next 16 bits are ones, and the remaining, least-significant 32 bits contain the IPv4 address. For example, ::ffff:192.0.2.128 represents the IPv4 address 192.0.2.128. A previous format, called "IPv4-compatible IPv6 address", was ::192.0.2.128; however, this method is deprecated.[61]
* https://en.wikipedia.org/wiki/IPv6#IPv4-mapped_IPv6_addresse...
* https://datatracker.ietf.org/doc/html/rfc4291#section-2-5-5
You still need to upgrade bit of networking kit between the source and destination to understand "IPv4+", and this (lack of) upgrading and enabling is what is hampering deployment.
What makes you think that companies would have been willing to make the effort to deploy "IPv4+" any more than IPv6?
> Because it is a mess. Stop denying that. If ipv6 was designed to be easily deployed via backwards compatibility then we would be using ipv6 already.
Backwards compatibile IPv6 was impossible.
IPv4 has 32 bits of address. Anything after IPv4 needed >32 bits of address. How do you fit in >32b in a data structure that is 32b? You cannot.
So you have to go an replace every bit of networking code out there to change the data structures. You know, like was done to deploy IPv6.