Proxy Server Cans and Cannots

Many experienced users wonder: “What can a proxy server do?” And they ask the opposite question: “What can’t a proxy server do?” First, let’s consider what a proxy server can do:

  1. Due to IP manipulations, a proxy allows increasing your presence anonymity on the net.

  2. Due to data caching, a proxy server acts as though accelerating your access to required resources (it applies to HTTP proxy).

  3. It helps to limit access of specific users to certain resources, impose limitations on handling various data (for example, you can limit the video download speed to some point and ban access to social networks in order to unload the communication channel).

  4. A proxy server allows filtering the content of transmitted data (it concerns the HTTP proxy), it helps restricting a banner download (the downloaded we-page will contain empty places instead of banners).

  5. Also, you can restrict access to proxies or ban various technologies (e.g. you can ban FTP usage).

Below you can see what a proxy can’t do:

  1. The semantic analysis of downloaded data is not implemented in proxies, it means you will not be able to ban some download based on key words, or completely cut off pages with mentioned keys.
  2. SOCKS-based proxy server, as distinct from HTTP, cannot filter the downloaded content.
  3. A proxy cannot accept an external request (however, SOCKS 5 protocol specification allows doing it, but it’s not easy to perform this task technically).
  4. There are plenty of other thing a proxy cannot do.