HyperText Transfer Protocol Simulator

Protocol Description

HTTP (Hypertext Transfer Protocol) is familiar as the mechanism for delivering web pages. HTTP operates over TCP (Transmission Control Protocol) in client-server mode for reliable transfer of data. URLs (Uniform Resource Locators) and information contents are represented symbolically in the simulation (URLn, DATAn). The protocol simulation deals with the main commands:

• GET: get data for URL
• HEAD: get header for URL
• POST: append data to URL
• xPUT: send data to URL

The simulation supports a limited range of response codes:

• 200 OK: the command completed successfully
• 301 MOVED: the requested URL has moved to another location
• 400 ERROR: the command encountered an error (not explicit in the simulation)

The protocol simulation shows a time-sequence diagram with client and server protocol entities, and a communications medium that carries messages. The client sends a one of the above commands and a URL. The server makes one of the above replies. Since the medium is assumed to be reliable, messages are never lost (though they may be delayed).

Protocol Parameters

This simulation has no parameters.

Protocol Simulation