alt Hacker NewsHuh. I believe that, but didn’t know it (I write apps for Apple kit). I have done low-level networking stuff that would definitely have run into issues, but that was over ten years ago. These days, I rely on the upper layer of the stack.
I really should try an exercise like the one the author did. I’m not necessarily against IPv6, but I’m still a bit skeptical of it. We’ll likely be forced into it, as there’s no alternative, but that’s not exactly a ringing endorsement.
Replies
Dagger2 • yesterday at 11:22 AM
If your low-level networking code (I assume you mean BSD sockets here) is correct, it shouldn't even need to be aware of v4 or v6. The BSD socket API is designed so that the addresses are in an opaque data structure that you just pass around.
My carrier (NTT docomo in Japan) only provides IPv6 to the end device. Access to IPv4 servers is through DNS64/NAT64, where their DNS server rewrites any DNS response that has an IPv4 in it to [64:ff9b::(the IPv4)] which gets handled by a CGNAT gateway. So anything that looks up a server over DNS and connects to that works fine, but any hard-coded IPv4 address does not.
I presume Apples requirement is there so that all apps work on carriers like this.
The only times I've run into issues is when tethering and forgetting I can't ping an IPv4, or trying to tether a Nintendo Switch (which does not support IPv6)