Reverse Proxy And Http Redirects; Understanding Reverse Proxy Caching; Reverse Proxy Solutions - HP P4535A - Web Cache Server Appliance Administrator's Manual

5 Reverse Proxy and HTTP Redirects

As a reverse proxy cache, Traffic Server serves requests on behalf of origin servers. Traffic Server is
configured in such a way that it appears to clients like a normal origin server.
Using HTTP redirects, Traffic Server routes HTTP requests automatically without contacting the origin
server.
This chapter discusses the following topics:
Understanding reverse proxy caching‚ on page 33
HTTP Reverse Proxy‚ on page 35
FTP Reverse Proxy‚ on page 39
Redirecting HTTP Requests‚ on page 43

Understanding reverse proxy caching

In forward proxy caching, Traffic Server handles web requests to distant origin servers on behalf of the clients
requesting the content. Reverse proxy caching (also known as server acceleration or virtual web hosting) is
different in that Traffic Server acts as a proxy cache on behalf of the origin servers that store the content.
Traffic Server is configured to be the origin server the user is trying to connect to (the origin server's
advertised hostname resolves to Traffic Server, which is acting as the real origin server).

Reverse proxy solutions

There are many ways in which Traffic Server can be used as a reverse proxy. Here are a few example
scenarios.
You can use Traffic Server in reverse proxy mode to:
Off load heavily used origin servers
Deliver content efficiently in geographically dispersed areas
Provide security for origin servers that contain sensitive information
Off loading heavily used origin servers
Traffic Server can absorb the main origin server request traffic to improve the speed and quality of service of
web serving by reducing load and hot spots on backup origin servers.
For example, a web hoster can maintain a scalable Traffic Server serving engine and a set of low-cost, low-
performance, less reliable PC origin servers as backup servers. In fact, a single Traffic Server can act as the
virtual origin server for multiple backup origin servers, as shown in Figure 5-1.
33