<networking> A server process that intercepts requests from a
client, passes them to an origin server and returns the response
to the client while performing various other operations in the
process. An HTTP proxy server is a common example. A proxy may
be used for purposes of security, performance (caching) or
anonymity. It may be purely software or may run on its own
hardware, either a standard PC or server machine or a custom
hardware appliance. A software proxy may be on the same computer
as the client or the origin server, separate hardware may be
anywhere on the network in between. The proxy may filter
requests, rejecting some if the request or response matches
certain conditions (e.g. an antivirus proxy). It may cache
requests and responses to reduce load on the origin server or
data volume on the network or to provide quicker response to the
client for common requests. The proxy may modify the request or
response, e.g. to convert between different protocols or
interfaces. Proxy servers are often used i