System Architecture of Forums 

The figure below illustrates how the components of a forums system work together.

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       1.      A user logs onto a forum and posts a message.

       2.      The forums application sends the incoming message through special filters, called interceptors. Interceptors screen the message for any content for which you have configured them. The interceptors do one of the following:

○       alter and pass on the message

○       allow it through unaltered

○       reject the message

       3.      The system applies permissions set at global, category, or forum level to the message.

       4.      The system saves the message in the database.

       5.      If a user is trying to view a particular message, the system retrieves this message from the cache or from the database.

       6.      According to the permissions the system decides whether to display the message to the user.

       7.      The message passes through filters that dynamically format the message content before it can be viewed by users.

       8.      The user reads the posted message.