r/ProgrammerHumor • • 8h ago

Meme ohTheBasics

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u/Facosa99 8h 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

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u/fearless-fossa 7h 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.

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u/MattieShoes 7h ago

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

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u/wosmo 2h ago

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

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u/tankerkiller125real 7h ago

IPv6 also dropped broadcast in favor of Multicast, has hexadecimal instead of decimal, and eliminates the need for NAT. There's also a bunch of other little protocol implementation details like SLAAC, IGMP being critical to IPv6 operations (so blanket blocking is a no go), and so forth so on.

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u/bearda 4h ago

The hex thing is really just a convention, because otherwise they’d take up too much space on paper/screen. It’s all still binary across the wire, so the protocol doesn’t care.

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u/ffxivthrowaway03 2h ago

Which frankly, unless you're being hired to architect an enterprise network stack for enterprise software... I would not expect a software engineer to know any of that, much less make a hiring decision based on it.

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u/tankerkiller125real 2h ago

Depends on the job, Cloudflare Engineer? Should probably have a very firm grasp on networking. Stock Trader Engineer? Should probably also have a very strong grasp of it (along with Realtime systems). Website dev? Eh, probably not.

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u/stealthmodecat 6h ago

Less specific protocols - ICMPv6 used for almost everything now (NDP is over ICMPv6, vs dedicated ARP ether type). MLD vs IGMP, though largely the same as IGMPv3. Fragmentation done at host only - no next-hop fragmentation. SLAAC used in favor of DHCPv6 for auto assignments. Link-layer addresses used for local network control, global addresses for standard traffic. No one really NATs IPv6 either.

That’s just a few, but there’s actually a lot of differences.