CACHE AND CARRY
TO DECIDE whether you need enterprise search now or can wait for offerings to mature, you need an idea of how much time your employees spend searching for content, the location of the content that employees are seeking and what the information is used for.
For salespeople who must pull results from e-mail, a file server and a Web server to build a proposal, federated search can bring a lot of value. For remote employees who keep a lot of data on their local drives, a search app that integrates tightly with the desktop, like X1's Enterprise client, is ideal. These have a multilevel architecture--desktop agents plus server-based indexing. The client can index the local computer and communicate with a "cluster" to search server file shares.
If you plan to turn on caching, you'll have to determine if you want just text cached, with no images, or the entire document. Obviously, the latter will greatly increase the amount of space needed. On the flip side, if full-document caching is enabled, users will still be able to query and view documents when the originating source is down, provided security information is also cached, or the infrastructure is such that the search engine doesn't have to verify rights against the originating source.
Another caveat of caching depends on how the software indexes a document. Some vendors don't index common words, which helps reduce the size of the index. The downside is, a separate document cache must be created, by caching the whole document or just the document text. The cache is needed to generate page summaries. Other vendors index every word at the cost of a larger index and the benefit of not needing to create a separate document cache. Because every word is contained in the index, summaries can be generated from the index, but this method of generating summaries can be slower than generating summaries from a document cache.
