Object Naming Service
Object Name Service (ONS) is a mechanism that leverages Domain Name System (DNS) to discover information about a product and related services from the Electronic Product Code (EPC). It is a component of the EPCglobal Network.
The Object Name Service (ONS) is an automated networking service similar to the Domain Name Service (DNS) that points computers to sites on the World Wide Web. When an interrogator reads an RFID tag, the Electronic Product Code is passed to middleware, which, in turn, goes to an ONS on a local network or the Internet to find where information on the product is stored. ONS points the middleware to a server where a file about that product is stored. The middleware retrieves the file (after proper authentication), and the information about the product in the file can be forwarded to a company's inventory or supply chain applications. 
It is published by the EPCglobal board. Version 1.0 of the specification was ratified by the board in October 2005.