Proxy

Security+ 🏆 • Network Security 🌐 • Web Security 🕸️ Difficulty: premium

Definition

A proxy is an intermediary system that receives a client’s request and forwards it to a destination on the client’s behalf. Proxies are used for security, privacy, performance, and control, such as filtering web traffic, enforcing policy, hiding internal addresses, and inspecting content.

Examples

  • A company routes employee web browsing through a proxy that blocks known malicious sites and logs access for investigation.
  • A reverse proxy sits in front of a web application to terminate TLS, apply security controls, and balance traffic across servers.

Discover 🔎

Networks are built on direct connections, but security often benefits from placing something in the middle. A proxy is that “something in the middle.” It can enforce rules, record activity, hide details, and sometimes inspect content. Proxies are common in corporate environments because they provide a control point for outbound web traffic and a protection layer for inbound web applications.

Remember: A proxy acts on behalf of the client. The destination sees the proxy as the requester, not the original device.
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