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0 pointsmagicalhippo1y ago0 comments

I'm just a casual homelab guy, but all my hardware now supports IPv6 but I'm not really using it precisely because it is just so different from IPv4.

How you assign addresses is completely different. How you configure your firewall as a result is completely different. In fact software support for the latter was one of the things I struggled with for years before having to change router software from pfSense to OpenWRT. Last I checked pfSense still didn't have full support.

They changed the way you write the addresses, using the port separator as group separator as well, leading to needing special software support for parsing IPv6 addresses. I know because I had to fix this in a few projects where we bothered to add IPv6 support, and that was the biggest PITA by far when adding IPv6 support, the rest was trivial.

Out of all the trouble I've had with IPv6, the wire format was the least problematic by far. All the wire format did was cause it to take some time to get IPv6 capable hardware.

But I've had that hardware for decades at this point. The thing keeping IPv6 back is all the other things they changed.

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Plasmoid1y ago

> They changed the way you write the addresses, using the port separator as group separator as well, leading to needing special software support for parsing IPv6 addresses. I know because I had to fix this in a few projects where we bothered to add IPv6 support, and that was the biggest PITA by far when adding IPv6 support, the rest was trivial.

OMFG!

The hardest part of supporting IPv6 was fixing your address parsing? THAT!?

Here's my frustration. Everyone who doesn't understand the why of IPv6 always complains that the address format is such a huge problem and that is why the IPv6 deployment is so slow and hard. It's basically a shibboleth for poor understanding.

The reason why this isn't a good take is that IP address parsing is a standard function of every standard library on the planet. You dump in a string and they all figure it out, and spit back an object with everything you need. The reason you had so much trouble with supporting it is that you weren't using the platform libraries. You hacked together some junk, probably a few broken regex's and string concatenation. Your homebrew IP library was broken and I guarantee you didn't handle all the IPv4 parsing rules correctly.

magicalhippoOP1y ago

> The hardest part of supporting IPv6 was fixing your address parsing?

That was actually a non-trivial part of implementing IPv6. Sure RFC 2732 had come out a few years earlier, but we weren't parsing URLs so it was not clear if it applied to our use-case.

All the rest that was required for us to support IPv6 was quite trivial. This was the only thing we had to spend time on.

> The reason why this isn't a good take is that IP address parsing is a standard function of every standard library on the planet.

Ok, I stand to be corrected, after all none of us were network programming experts.

How do you parse a IPv6 address, including the port number if present, using Boost 1.35 or C++03 STL? Note should run on Windows XP, as well as Linux and OSX of similar era. Does your solution require the format specified in RFC 2732?

Anyway my point still stands. There main friction to adopting IPv6 is not the wire format, it's everything else they changed.

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