IPv6 is the only way forward

Original Article ↗ Hacker News Discussion ↗

IPv4 vs IPv6: necessity and philosophy

  • One camp argues IPv6 is the only realistic path beyond the hard 32‑bit IPv4 limit, especially for late‑arriving regions.
  • Others say IPv4 “crisis” has been talked about for decades but NAT and CGNAT keep working; they expect IPv4 to remain dominant.
  • Some see IPv6’s “every host has a public address” model as fundamentally flawed and insecure; others note this was also IPv4’s original design and that firewalls, not NAT, should provide protection.

NAT, CGNAT, and P2P connectivity

  • Critics of CGNAT highlight: no true port forwarding, unreliable hole punching, degraded gaming and VoIP, mandatory relays, higher latency/cost, and overloaded carrier NAT boxes.
  • Skeptics downplay this, claiming most real‑world apps already rely on relays/tunnels and users mainly care about outbound web and streaming.
  • Debate centers on lost potential for simple P2P and home hosting versus the acceptability of client–server everything.

Backward compatibility and “IPv4 but bigger”

  • Several proposals suggest a hypothetical “IPv4+” or IPv8 with 64‑bit addresses, more compatible with IPv4 or easier to read.
  • Network‑savvy participants argue these are effectively new protocols with the same transition costs as IPv6: new packet formats, DNS records, APIs, and upgrades to all routers, OSes, and apps.
  • Comparisons to ASCII→UTF‑8 are rejected because IP headers are fixed‑size, not variable‑length like text encodings.

Usability, configuration, and tooling

  • Common complaints: long, non‑memorable addresses; SLAAC vs DHCPv6 confusion; dual‑stack doubling troubleshooting; inconsistent OS and router UX.
  • Others say v6 complexity is comparable to “IPv4 + ARP + DHCP”; issues are mostly poor CPE/router implementations and legacy scars.
  • Many emphasize DNS/mDNS and tools like Tailscale’s “magic DNS” as the real UX layer; memorizing IPs (v4 or v6) is seen as obsolete.
  • Some report concrete IPv6 pain: changing ISP prefixes breaking pfSense configs, Android’s SLAAC‑only behavior, and fingerprinting via stable global addresses (partly mitigated by privacy extensions).

Deployment realities and ecosystem gaps

  • Mobile networks and some residential ISPs heavily use IPv6 (often with NAT64/464XLAT); for many users “ping6 just works.”
  • Major gaps: ISPs that still offer no IPv6, enterprise networks that remain IPv4‑only, and large cloud/SaaS providers (e.g., GitHub, some Azure services) lacking full IPv6 support.
  • This fragmented support forces dual‑stack setups and deters operators who don’t see clear short‑term benefits.

Equity and address scarcity

  • Several comments frame IPv6 as an equity issue: early US/EU actors hold large IPv4 blocks, while countries like India and China must rely on CGNAT.
  • Proposals to “just reclaim” unused or government/enterprise IPv4 are argued to buy at most a short reprieve given growth and fundamental 2³² limits.