A public proxy is a proxy that is open and is usually found by port scanning. These proxies are also available for free in the public domain. A public proxy, also called an open proxy, does not work via closed network tunnel. Public proxies tend to burn out real fast as these proxies are so widely available.

Advantages of Public Proxies

  • Anonymous public proxies help users to hide their IP addresses from web servers or internet-based content providers. However, full anonymity cannot be achieved by an open or public proxy server.
  • These proxies are generally free to use.

Disadvantages of Public Proxies

  • A computer can run a public proxy server without any permission or configuration from the owner. This may result in misconfiguration of proxy software applications running on a system, or even malware attacks. When a computer is infected with malware programs that are designed for this particular purpose, it may become a zombie computer.
  • Illegal content may spread through public proxies.
  • Exceeding bandwidth limits is a common effect of using public proxies. This results in bandwidth limit violation.
  • Misconfigured public proxies may allow access to DMZ or private sub-network. This may cause a security threat to an office or home network.
  • Public proxies are usually very slow.
  • Many software programs have been developed that can easily detect a request coming from a public proxy server.

All in all, a public proxy may be way cheaper than shared or private proxies, but they burn out really fast and they are not as effective as shared or private proxy servers. Therefore, if you are using a proxy server for professional purpose, it should always be a private proxy server.