The Challenge

While NIEM provides a common vocabulary for information sharing, its scope does not cover specific implementation details such as how messages should be exchanged, what the actions for data records should be, or how federated searches should occur. NIEM is intended to be a building block for higher order data standards that can make use of a common nomenclature to layer additional constructs necessary to implement a complete solution.



The US DOJ created the Logical Entity Exchange Specification (LEXS) to address a number of issues that NIEM by itself did not cover. It provides a flexible, NIEM-based framework for information sharing, both for publishing information and for system-to-system federated searches. LEXS is the base message exchange standard used in the majority of federal data sharing initiatives by US DOJ and US DHS, including the FBI's NDEX initiative.

LEXS specifies a set of schemas that establish consistent definitions supporting publication, search, and retrieval, both at a data level and a structural level. LEXS data elements and structures are organized into components that support the underlying actions required to accomplish the publication, search, and retrieval operations fundamental to information sharing.

Two basic categories of operations are defined by LEXS:

• LEXS Publication and Discovery (LEXS PD) is for publishing and updating data from a source to a consumer. It is currently used for data owners (or submitters) to publish to OneDOJ, N-DEx and other information sharing systems.


• LEXS Search and Retrieval (LEXS SR) is for system-to-system federated searches and allows result drill-down to obtain more detailed information. It is currently used for interconnections between the government OneDOJ program and partner systems, such as LInX, ARJIS, T-DEx, etc.

Though LEXS provides a framework for dealing with data integration, the challenge is the degree of complexity required to implement these standards. Both are run-time interfaces intended to provide a specific, standardized mechanism for implementing warehouse and federated systems as shown below.

The Solution

The Sypherlink Harmonizer solution provides for an implementation of the LEXS standard using modular components that can be combined to implement small scale and large scale data integration solutions. Whether a project calls for feeding data to the FBI's NDEX system or building a data sharing solution for a small jurisdiction, the Sypherlink Harmonizer software is flexibile enough to address these needs. Please click on the link above for more detailed information about the product.