Why No IPv6?

Original Article ↗ Hacker News Discussion ↗

Regulation vs. market forces

  • Some argue IPv6 should be mandated (e.g., by governments or the EU) to fix market failures and prevent ISP/cartel pathologies.
  • Others see this as overreach and insist economics should drive adoption: when IPv4 becomes too expensive or constraining, companies will move.

Business incentives & IPv4 economics

  • For many organizations IPv6 brings little immediate, visible benefit: IPv4 “still works,” so IPv6 gets deprioritized or killed as “not a priority.”
  • IPv4 scarcity is real: public addresses are expensive, being bought and rented like real estate; some hosts and clouds charge extra per IPv4.
  • New/small ISPs and community networks report high costs and delays acquiring IPv4, forcing investment in translation/proxy gear.

Technical design and complexity of IPv6

  • Critics say IPv6 tried to “rewrite everything” instead of just enlarging the address space, introducing conceptual and implementation complexity (SLAAC vs DHCPv6, renumbering, no NAT-by-default, different local-network behavior).
  • Defenders counter that NAT was a hack, IPv6 routing is still simple prefix routing, and address autoconfiguration is, in principle, simpler than IPv4+NAT+DHCP.

Deployment, tooling, and dual-stack pain

  • Dual-stack is seen as a major burden: sites must support both but can’t yet drop IPv4, so IPv6 feels like extra work with no payoff.
  • Many consumer/SMB routers and ISP stacks handle IPv6 poorly or inconsistently, causing weird breakage; this reinforces the perception that IPv6 is “buggy.”
  • Chicken‑and‑egg: ISPs don’t push IPv6 because few sites require it; sites don’t enable it because most users are fine on IPv4.

NAT, CGNAT, and end‑to‑end connectivity

  • Some praise NAT as a proven scaling and security tool; others see it as a disaster that broke end‑to‑end connectivity and forced centralized, workaround-heavy designs (STUN/TURN, P2P issues).
  • Carrier‑grade NAT (and IPv4 exhaustion) already harms users: hard or impossible home hosting, double‑NAT, degraded performance, worse scraping detection, and higher infrastructure costs.

Adoption status and attitudes

  • Supporters note substantial and growing IPv6 traffic (especially mobile, some large networks going IPv6‑only internally) and working transition techniques (NAT64, DS‑Lite, 464XLAT).
  • Skeptics point to ~two‑plus decades of slow progress, lingering ISP/router issues, lack of consumer demand, and the fact that many major services still function fine on IPv4 only.
  • Overall tone: recognition that IPv4 is finite and increasingly contorted, but deep frustration with IPv6’s deployment complexity and incentives misalignment.