due to poor design choices in their white pages schema, such as: attributes used for naming purposes were non-unique in large environments (such as a person's common name) attributes used for naming purposes were likely to change (such as surnames) attributes were included which could lead to Identity theft, such as a Social security number users were required during provisioning to choose attributes which are unique but still memorable to them Numerous other proposed schemas exist, both as standalone definitions suitable for use with general purpose directories, or as embedded into network protocols. Examples of other generic white pages schemas include vCard, defined in , and FOAF. See also Recognition of human individuals Data modeling Data management Identity management