Web proxy servers are intermediaries. Proxies sit between clients and servers and act as “middlemen,” shuffling HTTP messages back and forth between the parties.This chapter talks all about HTTP proxy servers, the special support for proxy features, and some of the tricky behaviors you’ll see when you use proxy servers.
In this chapter, we:
Explain HTTP proxies, contrasting them to web gateways and illustrating how proxies are deployed.
Show some of the ways proxies are helpful.
Describe how proxies are deployed in real networks and how traffic is directed to proxy servers.
Show how to configure your browser to use a proxy.
Demonstrate HTTP proxy requests, how they differ from server requests, and how proxies can subtly change the behavior of browsers.
Explain how you can record the path of your messages through chains of proxy servers, using Via headers and the TRACE method.
Describe proxy-based HTTP access control.
Explain how proxies can interoperate between clients and servers, each of which may support different features and versions.