March 12, 2026
Ports, penguins, and packet dreams
The Road Not Taken: A World Where IPv4 Evolved
Geeks dream up ‘IPv4x’ — and the comments explode over addresses, nostalgia, and hacks
TLDR: A thought experiment imagines “IPv4x,” a backward‑compatible way to make internet addresses huge without breaking old devices. Commenters split between retro dreams, jokes that ports already turned IPv4 into a hacky upgrade, and fears about compatibility—highlighting why IPv6 adoption remains a messy, slow standoff.
What if the internet never moved on and just bolted a mega‑garage onto IPv4? That’s the thought experiment behind “IPv4x,” a fantasy upgrade that keeps today’s addresses but tucks extra space into the packet—so old gear still works and new gear sees a vast new neighborhood. The crowd went wild.
The nostalgia squad rolled in first: one commenter pined for “36‑bit addressing like the PDP‑10,” claiming 64 billion “phone numbers” might’ve dodged the shortage drama. The snark brigade fired back with the meme of the day: “IPv4 already evolved—it’s 48‑bit now: IP:PORT,” translation: we crammed everything behind one address using ports and tricks, like stuffing an entire family plan onto one phone. Meanwhile, the killjoy realists poked holes in compatibility: if an old device only knows a 32‑bit address, how does it reach a 128‑bit destination? Cue existential router panic.
Then came the classic hot link: “The IPv6 mess”, tossed like a grenade. Others argued the real sin wasn’t IPv6 itself (the bigger‑address successor) but deploying it like it’s still IPv4, missing its new powers. Underneath the jokes about penguins taking the first plunge, the thread split: dreamers who love a backward‑compatible upgrade vs. pragmatists who say we’ve already hacked our way here—and it kinda hurts.
Key Points
- •The article presents a hypothetical IPv4 extension, “IPv4x,” designed in 1993 to expand addresses while remaining backward compatible.
- •IPv4x would keep Version=4 and a 32‑bit destination in the header, embedding an additional 96 bits of source and destination address in the packet body, flagged in the header.
- •Legacy IPv4 routers would route based on the 32‑bit address, while IPv4x-capable routers would use the full 128‑bit address for routing.
- •Ownership of address space would map directly: each IPv4 address holder would own the corresponding 96‑bit subspace beneath it.
- •The proposal is motivated by IPv4 exhaustion, the widespread use of NAT/Carrier-Grade NAT, and slow adoption of IPv6 despite its technical advantages.