The best replacement for nat is pat.

The best alternatives to nat are rated as following:
★★★★★  pat
★★★  bridged
★★  dhcp
★  dmz
★  proxy
★  port forwarding
★  firewall
★  napt
★  rip
★  bridge
★  dynamic routing
★  routing
★  pat cisco
★  bridge mode
★  snat
★  gnat
★  nat network
★  spi
★  natalie
★  dns
★  stro
★  route
  classical routing
  bridged virtualbox
  cidr
  nat
  pcr
  ipv6
  host-only vmware
  router mode
  phil
  ics
  bridged adapter
  bridged mode
  dynamic nat
  fruit fly
  bridged vmware
  knat
  spi firewall

Your alternative for nat is not listed? Suggest!
Speaking about nat, one probably shouldn't forget about iptables.

Other search terms related to nat and their ratings are:
★★★★★ iptables
★★★★ dhcp
★★★★ vpn
★★★ ipv6
★★ pat
★★ port forwarding
★★ firewall
★★ vrf
★ linksys router
★ router on a stick
★ hsrp
★ vyatta
★ router access
router
cisco
route maps
You have in mind a companion for nat and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of nat in all years. Click on graph for more.
nat
pat
bridged