ISAN can be used with the major audiovisual standards used in content production and distribution. Several standards have a specific ISAN field and others are using generic URN (Universal Resource Name). ISAN is a registered Universal Resource Name (URN), therefore the ISAN URN representation can be used everywhere a URN is accepted as content identifier. ETIF RFC 4246 defines the formal URN and Namespace Identifiers (NID) for ISAN.