Nodeshave a BrowseName Attributethat is used as a non-localised human-readable name when browsing the AddressSpaceto create paths out of BrowseNames. The TranslateBrowsePathsToNodeIds Servicedefined in OPC 10000-4can be used to follow a path constructed of BrowseNames.
Subclause 8.3defines the structure of the BrowseName. It contains a namespace and a string. The namespace is provided to make the BrowseNameunique in some cases in the context of a Node(e.g. Propertiesof a Node) although not unique in the context of the Server. If different organizations define BrowseNamesfor Properties, the namespace of the BrowseNameprovided by the organization makes the BrowseNameunique, although different organizations may use the same string having a slightly different meaning.
Serversmay often choose to use the same namespace for the NodeIdand the BrowseName. However, if they want to provide a standard Property, itsBrowseNameshall have the namespace of the standards body although the namespace of the NodeIdreflects something else, for example the local Server.
Standards bodies defining standard type definitions shall use their namespace(s) for the NodeIdof the TypeDefinitionNodeas well as for the BrowseNameof the TypeDefinitionNode. BrowseNames ofTypeDefinitionNodes, ReferenceTypes, and DataTypes shall be unique. Anywell-knowninstancesusedasentrypoints shall also be unique. Forexample,theRoot Node definedinOPC 10000-5.
The string-part of the BrowseNameis case sensitive. That is, Clientsshall consider them case sensitive. Serversare allowed to handle BrowseNamespassed in Servicerequests as case insensitive. Examples are the TranslateBrowsePathsToNodeIds Serviceor Eventfilter. If a Serveraccepts a case insensitive BrowseNameit needs to ensure that the uniqueness of the BrowseNamedoes not depend on case.