I don't think we need DNS64 just because the alternative is 464XLAT. As long as applications use the system for DNS (eg. getaddrinfo), the OS can synthesize the equivalent of DNS64 from the PREF64. (For apps that do DNS themselves, there's a good chance they DoH anyway).
Then what remains as on-the-wire DNS64 is only used by OSes that don't process PREF64, and at least in v6mostly nets, they are in the fraction of legacy hosts that don't send option 108 and thus get v4 via NAT.
chrysn
npub1st…99zp6
2025-11-23 16:09:38 UTC
in reply to nevent1q…pvdw
Author Public Key
npub1st5k4cl9vwxme9afyh2z6n08vwn06wfg2ypud62k30hsmrrrdyvs299zp6Seen on
wss://relay.momostr.pinkPublished at
2025-11-23 16:09:38 UTCEvent JSON
{
"id": "68b033481621c3708c381dbac62b38b46f2880ee69f0c5a3833707f75f78c80d",
"pubkey": "82e96ae3e5638dbc97a925d42d4de763a6fd39285103c6e9568bef0d8c636919",
"created_at": 1763914178,
"kind": 1,
"tags": [
[
"p",
"f9d775eb638c05c904dc2333bbe328b52561e2e2da42e3cbea73230079560a02"
],
[
"e",
"d6ec3daf1df032b8e09850e4a64a574d8da9638d42ac1c892b1ded87cb8cc755",
"",
"root",
"f9d775eb638c05c904dc2333bbe328b52561e2e2da42e3cbea73230079560a02"
],
[
"proxy",
"https://chaos.social/@chrysn/115599879634812536",
"web"
],
[
"e",
"ba4aa086450ba4d5091d5645267798b031ced6ee3716b95bf815421f2237b0c8",
"",
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[
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"5ae0bc70b0339b90c5a312c13dccf19c3b2b705c2d87d95fc57b740136aa4f10"
],
[
"proxy",
"https://chaos.social/users/chrysn/statuses/115599879634812536",
"activitypub"
],
[
"L",
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],
[
"l",
"pink.momostr.activitypub:https://chaos.social/users/chrysn/statuses/115599879634812536",
"pink.momostr"
],
[
"-"
]
],
"content": "I don't think we need DNS64 just because the alternative is 464XLAT. As long as applications use the system for DNS (eg. getaddrinfo), the OS can synthesize the equivalent of DNS64 from the PREF64. (For apps that do DNS themselves, there's a good chance they DoH anyway).\nThen what remains as on-the-wire DNS64 is only used by OSes that don't process PREF64, and at least in v6mostly nets, they are in the fraction of legacy hosts that don't send option 108 and thus get v4 via NAT.",
"sig": "02130b911647c39a10a79c1b8cb915b4d4e1ce72cc4c9a11f069d8e65ae0b51a944169817b4c381d645c9a9121f8c099c25edb564847a747ec97b98f0fa5ee42"
}