To engineer a search engine is a challenging task. Search engines index tens to hundreds of millions of web pages involving a comparable number of distinct terms. They answer tens of n-tillions of queries every day. Despite the importance of large-scale search engines on the Web, very little academic research has been done on them. Furthermore, due to rapid advance in technology and web proliferation, creating a web search engine today is very different from years ago. In most papers the index simply ”is”, without discussion of how it was created. But for a indexing scheme to be useful it must be possible for the index to be constructed in a reasonable amount of time, and so papers describing complex indexing methods should also describe and analyze a mechanism whereby the index can be built.
Scalability is of concern during index construction as well as during query processing. This paper describes the cooperative work between the Crawler, Indexer and the Searcher.