Metadata Interoperability and Crosswalks:
There is no single universal metadata standard. Each community has its own requirements for describing resources and different standards (and profiles of these standards) have been developed to meet community needs. For example, the Dublin Core standard was developed to define a set of elements that could be used by authors to describe web-based documents. The International Organization for Standardization (ISO) 19115 standard defines a scheme for describing geographic information and services and specifically provides information about the spatial and temporal aspects of geographic data. It is important to remember that different metadata schemes can be used to describe the same resource and to serve a number of user groups.
Interoperability allows content or systems to work together through the use of agreed standards and specifications. Creating and maintaining metadata consistent with agreed standards is essential to ensure interoperability.[1] It is one of the most important principles in metadata implementation as it facilitates the exchange and sharing of data and enables cross-domain searching.
One of the problems of crosswalking is the different degrees of equivalency where there may not be a direct one-to-one mapping so there is no exact equivalent. Some elements could also overlap in meaning and scope and the resulting data conversion based on crosswalks could create quality problems.