This section explains how web browsers talk to servers in order to gather web pages. It explains how to use the telnet
command and a visual tool called TCPMON (http://ws.apache.org/commons/tcpmon/tcpmontutorial.html) to gain insight into how web services and Web 2.0 technologies work.
It turns out that message passing occurs via text commands between the browser and the server. Web browsers use HTTP (http://www.w3.org/Protocols/rfc2616/rfc2616.html) to get web pages and the embedded content from the server and to send form information to the server. HTTP talks between the client and server via text (7-bit ASCII) commands. When humans talk with each other, they have a wide vocabulary. However, HTTP uses fewer than twenty words.
You can directly experiment with HTTP using a Telnet client to send your commands to a web server. For example, if your demonstration Sakai instance is running on port 8080, the following command will get you the login page:
telnet localhost...