The W3 architecure

In order to implement a system providing the model above, a client-server architecure is clearly required (see figure). This is because all the intelligence for the user interface must clearly be on the user's local worksation, while any search engine must be atthe site of the data to be searched. Most IR systems with good human interface match this model.

The network protocols use high-level means of describing the data to be transferred, so that the presentation of the document on a user's screen