What is a proxy server?

A proxy server is an intermediary that makes connections on behalf of other devices: a computer asks the proxy for a web page, and the proxy fetches it. Companies use proxies to filter websites, keep logs of web access, or cache content. Some proxies inspect encrypted traffic by decrypting and re-encrypting it, which requires installing a company certificate on every device and raises privacy questions. Attackers use proxies too, to hide where their traffic comes from. A network sensor that sees connections pile up toward one unexpected proxy or anonymising service has found something worth checking. NetSenX never decrypts traffic and does not act as a proxy.

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