查看“Renn”的源代码

A Proxy is a software package that resides in-between a client computer and a host. All communication between the host and the customer are routed through the proxy. The application can reside either on a dedicated computer, sandwiched between the client and the host, or exist in the client computer it self. The proxy acts such as for instance a filter that sifts all communication that occurs between the machine and the client. 

Proxies are popular in the organization setting to regulate the internal computer systems conversation with the surface world. The entire information stream is limited through the proxy for protection and policy implementation functions. Any data that violates business policy or poses a threat to the interior networks safety is straight away filtered. Proxies are also found in educational institutions and public facilities like libraries for the very same purpose.  [http://www.entrust.net/code-signing/index.htm ssl]

Proxies can be used for an extensive number of applications. Centered on their functions, they are called by different names. a Content Filtering Proxy a proxy that is used for monitoring and selection information, as explained earlier, is known. On a Gateway another hand, a proxy that transfers all connection without changing the contents of the traffic is known. 

A Caching proxy is the one that maintains a cache of frequently requested information. It is generally used to cut back bandwidth usage and to speedup the network. The proxy normally passes that request to the server and relays the response from the server back to the client, whenever a client needs a bit of information. But if the same piece of information is requested over repeatedly, the proxy keeps a of that information in its cache and directly sends that information to the customer instead of sending a request to the server. This speeds up reaction time and also reduces the bandwidth dependence on the entire system.