The HTTP Protocol

• Requires: a connection between client and server
• Stateless: no login process, each request is independent
• Simple format: request header, blank line, possible payload
• Symmetrical: allows data to be sent and recieved
• Very easy to implement but scales very well

Example HTTP Request

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What do each of these headers mean? Which are required? Many are defined in the HTTP standard but others can be defined via the HTTP extension framework.

Example HTTP Response

Example HTTP POST Request

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This is a POST request, note how the data is encoded in the request body.

Example HTTP GET Request

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This is the same form submitted via a GET request, here the data is encoded in request URL. Note also the If-Modified-Since header in this request, sent because my browser has just asked for the same resource.

HTTP Redirect

Alternately

The HTTP redirect is a server response that can be used to indicate that a resource has moved to a new location. An alternate is to include the above meta tag in a page header to force a redirect from the current page.

HTTP Verbs