SRU (Search/Retrieve via URL) is a standard synchronous search protocol for Internet search queries, utilizing CQL (Contextual Query Language), a standard syntax for representing queries. SRW (Search Retrieve Web Service) is a companion protocol to SRU. The Library of Congress serves as the maintenance agency for these standards.
Other emerging standards for information protocols are reviewed in a paper given by Sally McCallum at IFLA 2006 in Seoul.
Last update: 5 December 2017