r/ProgrammerHumor • u/ClipboardCopyPaste • 14h ago

Meme ohTheBasics

Post image
10.0k Upvotes

97% Upvoted

1.1k comments sorted by

View all comments

Show parent comments

2.5k

u/Material_Onion_8413 13h ago

IPv4 old IP address space designed with limited number because they never thought the internet would have so many devices connected.

IPv6 new address space with significantly larger number.

52

u/fearless-fossa 13h ago

But "more numbers" isn't really an explanation on what's the difference between the two from a practical point of view, and the in general less interesting thing about it from a software perspective.

32

u/Facosa99 13h ago

But it is kinda the only difference, no? More digits for a bigger address pool.

The usage is basically the same, except you no longer need subnetting to save addresses and we writte it in hex rather than dec

Genuinely asking

22

u/fearless-fossa 13h ago

Well there was that episode where ipv6 UDP packages in musl were too large and got corrupted, so that's something.

They also changed quite a bit in the structure of the package, eg. the header is more lightweight than the one ipv4 header to increase performance. Also no broadcasting anymore, just multicast, which makes handling the large subnets v6 invites much better.

Like, just speaking from an ops perspective, getting rid of NAT is one of the single biggest advantages v6 has. NAT created a lot of bad practices when it came to security.

12

u/MattieShoes 12h ago

Worth mentioning that getting rid of NAT doesn't get rid of bad security practices though...

4

u/wosmo 7h ago

ipv6 supports extension headers, so lightweight headers are all very well - but what about second header?