Attributes for AD Users : telephoneNumber
The AD attribute telephoneNumbercan contain the primary telephone number where the user is available at work.
telephoneNumber
| LDAP name | telephoneNumber |
| Data type | String (max 64) |
| Multivalue (Array) | No |
| System Flags | 0x10 |
| Search Flags | 0x0 |
| In Global Catalog? | Yes |
| Attribute ID | 2.5.4.20 |
| AD DB attribute name | Telephone-Number |
| ADSI datatype | 3 - String(Unicode) |
| LDAP syntax | 1.3.6.1.4.1.1466.115.121.1.15 - Directory String |
| Used in ... | > W2K |
| Schema Info | Microsoft - MSDN |
This field isn't used directly from the Active Directory system, it is a pure info attribute without technical meaning. However, the telephoneNumber attribute is could be used used if some unified messaging system is installed which is based on Active Directory data.
Please note that there is another multivalue attribute named otherTelephoneNumber, which can hold a list of additional telephone numbers for the user.