6.3.1 Archival Information Package (AIP)  The definition of the term Archival Storage in OAIS includes the services and functions necessary for the storage of theArchival Information Package (AIP). Archival storage encompasses data management and includes processes such as storage media selection, transfer of AIP to storage system, data security and validity, backup and data restoration, and reproduction of AIP to new media.  AIP, as defined in OAIS reference model (CCSDS 650.0-B-1 Reference Model for an Open Archival Information System (OAIS)), is an information package that is used to transmit archival objects into a digital archival system, store the objects within the system, and transmit objects from the system. An AIP contains both metadata that describes the structure and content of an archived essence and the actual essence itself. It consists of multiple data files that hold either a logically or physically packaged entity. The implementation of AIP can vary from archive to another archive; it specifies, however, a container that contains all the necessary information to allow long term preservation and access to archival holdings. The metadata model of OAIS is based on METS specifications.  From physical point of view the AIP contains three parts; metadata, essence and packaging information, which all consists of one or more files (see 6.1.3 Defining the Digital Object). Packaging information can be thought as wrapper information and it encapsulates metadata and essence components.