IPv6 was designed to eliminate NAT. With undecillion addresses, every device can have a public IP.
IPv6 benefits over NAT:
- True end-to-end connectivity
- No translation overhead
- P2P applications work natively
But IPv6 adoption is slow:
- Many legacy systems only support IPv4
- Existing IPv4 infrastructure
- Dual-stack increases complexity
Current reality:
- Many networks run dual-stack (IPv4 + IPv6)
- IPv4 traffic still uses NAT
- IPv6 traffic goes directly
NAT66: NAT for IPv6 exists but is controversial. It violates IPv6 design principles.