The index server indexes and classifies documents and answers search queries. The processing takes place in the engines that belong to the index server. There are the following engines:
This engine is responsible for standard search functions such as the exact, error-tolerant, linguistic, Boolean, and phrase searches.
This engine is responsible for classification, searching for similar documents ('See Also' search), the extraction of key words, and so on.
This engine is responsible for searching for document attributes such as author, creation date, and change date.