Glossary · Networking
IP address
The numeric label that identifies a device on a network and is the address a proxy substitutes for your own.
An IP address is how the internet knows where to send a reply. Every request you make carries yours, and every server you talk to sees it, which is why it is the single most revealing thing about the origin of your traffic: it pins you to a network, and through that network to a rough location and an owner.
A proxy exists to swap that label. Instead of the destination seeing your address, it sees the proxy's, and everything a site infers about you, where you are, what network you are on, whether to trust you, it infers from the substitute instead. Change the address and you change the story.
Not all addresses are equal in what they reveal. The same string of numbers can belong to a home, a data center or a phone, and that ownership, far more than the number itself, decides how a site treats it.
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