It shows the relationship between the entry and the rest of the DIT in a manner similar to the way in which a file's full path name shows its relationship with the rest of the files in a filesystem. While a path to a file reads left to right, a DN, in contrast, reads from right to left. LDAP attributes often use mnemonics, some examples of which are listed in Table 1. Surname givenname First name uid Userid dn Distinguished name mail Email address Table 1. Some common LDAP attributes Information about attributes, attribute matching rules, and relationships between objectclasses are defined in the server's schema.
Any attribute can have one or more values, depending on how it is defined the schema.
A user, for example, can have more than one email address. There is also a special attribute called an objectclass that specifies the required and allowed attributes for a particular entry. Like objects in Java, objectclasses in LDAP can be extended to retain existing attributes and add new ones. A naming service associates names with objects and finds objects based on their given names. Many naming services are extended with a directory service.