4 ms·

"Ipv4 with more bits" could have a very simple cut-over. You internally update your stack and networks. Up until the cut-over date, the addresses are truncated

"Ipv4 with more bits" could have a very simple cut-over. You internally update your stack and networks. Up until the cut-over date, the addresses are truncated into IPv4. After the cut-over, they're routable. This could have been given a time table of say 5 years.

p_l 3y ago
No, it didn't work. Other than already mentioned issues of hardware, you also had for years the issue of lots of applications requiring substantial rewrite to support another protocol due to use of BSD Sockets which leaked protocol internals up to application layer. It was a very big and vocal issue about porting to v6 even in early 2000s despite BSD Sockets finally getting a new API (lifted from the Streams-based XTI) that made handling dual stack easier - but everyone still learnt from older manuals. And tricks with time table were tried - vendors would lobby for all sorts of extensions "while they work to update the code", the result was that none did because none wanted to actually put the work to upgrade network stacks and handle dual-stack in applications. After all, IPv6 is not the first attempt to replace the "temporary" solution that was IPv4 whose planned EOL was in 1990.
- comex 3y ago
  > you also had for years the issue of lots of applications requiring substantial rewrite to support another protocol due to use of BSD Sockets Past tense? I still regularly see code that uses BSD sockets and doesn't support IPv6. Actually, I feel like among C and C++ codebases that make direct TCP or UDP connections, the majority are IPv4-only, even in 2023. Though, direct TCP and UDP connections themselves are less popular than they used to be, and so are C and C++...
  - p_l 3y ago
    Past tense on have to write two complete code paths to support v4 and v6 at the same time. Today we have getaddrinfo, so if you're writing from scratch you can just use that, you can also simplify older code with it and get v6 at the same time. But there's a lot of old code that still doesn't use GAI and was never upgraded.
  - deleted 3y ago
    [deleted]
Dagger2 3y ago
v6 basically is v4 with more bits. You could do what you describe with it. The problem is that nobody has the authority to enforce such a timetable on the Internet as a whole, so that's not actually a workable plan.

p_l 3y ago

No, it didn't work. Other than already mentioned issues of hardware, you also had for years the issue of lots of applications requiring substantial rewrite to support another protocol due to use of BSD Sockets which leaked protocol internals up to application layer. It was a very big and vocal issue about porting to v6 even in early 2000s despite BSD Sockets finally getting a new API (lifted from the Streams-based XTI) that made handling dual stack easier - but everyone still learnt from older manuals. And tricks with time table were tried - vendors would lobby for all sorts of extensions "while they work to update the code", the result was that none did because none wanted to actually put the work to upgrade network stacks and handle dual-stack in applications. After all, IPv6 is not the first attempt to replace the "temporary" solution that was IPv4 whose planned EOL was in 1990.

comex 3y ago
> you also had for years the issue of lots of applications requiring substantial rewrite to support another protocol due to use of BSD Sockets Past tense? I still regularly see code that uses BSD sockets and doesn't support IPv6. Actually, I feel like among C and C++ codebases that make direct TCP or UDP connections, the majority are IPv4-only, even in 2023. Though, direct TCP and UDP connections themselves are less popular than they used to be, and so are C and C++...
- p_l 3y ago
  Past tense on have to write two complete code paths to support v4 and v6 at the same time. Today we have getaddrinfo, so if you're writing from scratch you can just use that, you can also simplify older code with it and get v6 at the same time. But there's a lot of old code that still doesn't use GAI and was never upgraded.
- deleted 3y ago
  [deleted]

Dagger2 3y ago

v6 basically is v4 with more bits. You could do what you describe with it. The problem is that nobody has the authority to enforce such a timetable on the Internet as a whole, so that's not actually a workable plan.