2.2.2 Properties that Apply to Containers in the Address Book Hierarchy Table
An address book is a collection of Address Book objects, each of which is contained in any number of address lists. The address book is arranged as a hierarchy of address book containers. Each address book container, in turn, describes an address list that contains many Address Book objects.
When using an offline address book (OAB), messaging clients SHOULD obtain information about the address book hierarchy and its address book containers by using the Offline Address Book Retrieval File Format, as specified in [MS-OXWOAB], or MAY<6> obtain information by using the Offline Address Book Public Folder Retrieval Protocol, as specified in [MS-OXPFOAB]. Because an OAB maintains its own structure for the hierarchy table, none of the properties of address book containers described in this document apply to the OAB.