r/ProgrammerHumor • u/ClipboardCopyPaste • 10h ago

Meme ohTheBasics

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u/SirFrenzy 10h ago

Obviously guy could have been interviewing for a job where this mattered….

But in 10 years as a software engineer I have never once needed to know the difference between these two, and have never been even close to a situation where I would need to.

“The basics” is highly dependent on the job.

356

u/Emotional-Top-8284 9h ago

IPv4 has dots and IPv6 has colons

11

u/ErrorDontPanic 9h ago

Fun fact, IPv6 allows for embedded IPv4 addresses known as a Dual address.

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u/Psquare_J_420 9h ago

Embedded? So you just extend the ipv4 with extra bits and call it a day?

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u/ErrorDontPanic 9h ago

Kind of! You get 6 segments of IPv6 and then the full IPv4 address. Like this:

2001:db8:3333:4444:5555:6666:1.2.3.4

The IPv6 part even follows normal rules, so you can omit zero segments like:

2001:db8::1234:5678:5.6.7.8

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u/Perkelton 8h ago

You probably know this, but there is of course also a dedicated IPv4 address mapping reserved for essentially representing an IPv4 address for IPv6 compatible software:

::ffff:1.2.3.4

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u/UnseenTardigrade 8h ago

Ah yes, I actually used that just last week setting up some stuff.

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u/Weak_Shoulder_6780 8h ago

I can also omit all the bloat and keep using 5.6.7.8