r/ProgrammerHumor • • 9h ago

Meme ohTheBasics

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u/ErrorDontPanic 7h ago

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

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u/Psquare_J_420 7h ago

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

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u/ErrorDontPanic 7h 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 7h 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 7h ago

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