Semantic search is a hot topic in the Search Engine industry. It is often seen as the next big thing on the Web, and some even foresee as constituting Web 3.0.

Beyond all the hype and the predictions, it is interesting to take a step back and ask exactly what semantic search is and what it means for the enterprise. Are we already using semantic technologies today? What does it change for me as a search engine user?

This post introduces a series of articles on semantic search and its applications in Exalead’s technology. Before we venture further, let’s begin with a very basic explanation what semantic search is.

“Semantic search” is information search in which a search engine better understands (or at least behaves as though it better understands) what you are really looking for when you type a search query.

It is made possible by “natural language processing” technologies, which seek to teach computers to understand and use language the way we human beings do, that is to say to be able to read, write, analyze or speak human languages like English or Spanish.

Semantic search, therefore, goes beyond mere keywords to leverage context and collective knowledge for a clearer understanding of your request (just as we do when communicating with each other). This is true whether the semantic search engine seeks to understand natural language sentences like “I’m looking for a good book on gardening,” or simply to better understand the range of possibilities and connections embedded in a keyword request like “sales presentation.”

Semantic search on the Web, when presented in a format that’s neither overwhelming nor overly restrictive, certainly provides a more enjoyable, more fruitful search process for the general public.

For businesses, semantic search offers a significant ROI by enabling faster, more accurate information retrieval, and by fostering creative discovery and collaboration (with connections between people and data being an integral part of semantics-based navigational systems for business).

All applications critically relying on that accuracy, like compliance and e-discovery or Business Intelligence and Information Lifecycle Management, are leveraged by the ability of the search engine to deliver the right information, even when the user has difficulty formulating what he or she is looking for.

In short, semantic search is a way to add value to your data and capitalize on your company’s knowledge and information.

The next post will extend these thoughts and present the additional features and functionalities brought by semantic technologies in a search engine, how it enriches your experience as a user and eventually benefits the company as a whole, enhancing opportunities and competitive advantages.

Reference: Exalead one:search Semantics White Paper

Join us Thursday, February 28, 2007, 12:00-1:00 p.m. Eastern Time for the KMWorld Webinar “Leveraging the Power of Unified Information Access for Effective Knowledge Management.”

Exalead co-founder François Bourdoncle and Steve Rappaport, Director of Knowledge Solutions for The Advertising Research Foundation (ARF), will discuss ARF’s experience in implementing an online knowledge-base. Also on the agenda, hot trends in information access, including the growth of hybrid vertical search applications in business.

Register now for this FREE webinar:
http://www.kmworld.com/webinars/register.aspx?eventid=279&src=kmb

A good search platform provides easy, quick, universal access to business information while ensuring users can only see and access content for which they have the necessary read authorization. Ensuring confidentiality in the context of enterprise search means that the search solution doesn’t seek to replace or even alter the existing security policies.

In addition, an enterprise search solution should accommodate an organization’s tolerance for latency in permissions changes. During the process of generating results, a secure search engine needs to match the authenticated user’s access rights with the retrieved documents’ access rights (defined in Access Control Lists, or ACLs).

To determine a user’s read rights for a particular resource when executing a search query, there are two basic options, each with a different impact on latency:

• Real-Time ACL Checking (sometimes referred to as “unmapped security” or “post-query filtering”): the search platform checks the ACL at query time for each individual search result returned by a query.

• ACL Indexing (also known as “mapped security” or “ACL mapping”): at indexing time, information regarding the users and their rights is appended as metadata to the index entry for a document. Consequently, at query time, the search platform simply checks the metadata attached to each index entry rather than checking with the source application’s ACL.

Because Real-Time ACL Checking is hard to manage and puts a heavy load on the server and incumbent systems, Exalead recommends ACL Indexing as a standard approach. It is the fastest, most scalable option. It also offers a very high level of granularity.

However, there is latency in permissions changes with ACL Indexing, which may be unacceptable in certain contexts. Therefore, exalead one:enterprise can optionally combine the two ACL checking methods to optimize performance while ensuring a responsive approach to changes in security access rights.

To learn more about how security works in the context of enterprise search, and about Exalead’s approach to security, you can request a copy of our white paper “Secure Search Solution” by emailing us at contact@exalead.com.