TCP/IP is the foundational suite of networking protocols that governs how data is broken into packets, addressed, transmitted, and reassembled across the internet. Every proxy connection ultimately runs on top of TCP/IP, which handles the low-level mechanics of getting data from your device to a proxy server and on to its final destination.

TCP vs. IP, Defined

  • TCP (Transmission Control Protocol), handles reliable, ordered delivery of data
  • IP (Internet Protocol), handles addressing and routing

Understanding TCP/IP isn't necessary for most proxy users, but it's where concepts like "IP address" and "port" come from, and the protocols proxies use run on top of it.

TCP's reliability guarantees come at a cost: every dropped packet has to be re-sent, which is part of why TCP is slower than protocols like UDP that skip those guarantees.