The best replacement for proxy server is firewall.

The best alternatives to proxy server are rated as following:
★★★★★  firewall
★★★★★  vpn
★★★  nat
★  web server
★  dns server
★  dmz
  packet filter
  lan
  no proxy server
  isa server
  load balancer
  automatic configuration script
  server
  destination origin server
  reverse proxy server

Your alternative for proxy server is not listed? Suggest!
Speaking about proxy server, one probably shouldn't forget about firewall.

Other search terms related to proxy server and their ratings are:
★★★★★ firewall
You have in mind a companion for proxy server and it is not yet here? Propose!



Google Trends

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proxy server
firewall
vpn