6.1.2 COOPERATING ARCHIVES
Cooperating Archives are based on standards agreements among two or more Archives. The simplest form of cooperation between Archives is when one Archive acts as a Consumer of material from another Archive. In this case the consuming Archive must support the DIP format of the producing Archive as a SIP format. Cooperating Archives have related communities of interest, so they order and ingest data from other cooperating Archives and possibly have common data Producers. No common access, submission or dissemination standards are assumed. The only requirement for this architecture is that the cooperating groups support at least one common SIP and DIP format for inter-Archive requests. The control mechanism for this sort of inter-operation can be Event Based Order requests at each Archive.
Figures 6-1 and 6-2 illustrate the concept of cooperating Archives.
At a rudimentary level of Archive interaction, figure 6-1 represents a simple mutual information exchange agreement between Archives.
NOTE – In this and the following figures, the OAIS is represented as a multi-port device following the arrangement of figure 6-1. In each case, a two-Archive federation is shown for simplicity, although the concept can be extended indefinitely.
The essential requirement for this federation is a set of mutual Submission Agreements, Event Based Orders, and user interface standards to allow DIPs from one Archive to be ingested as SIPs by another. Therefore, it assumes that some pair-wise compatibility has between established between the Archives. This does not necessarily require common access, dissemination and submission methods for all participants, although that might encourage more exchange. This level of agreement would also be useful when the holdings of one Archive were consolidated/transferred into another Archive because of Management issues.
Figure 6-1: Cooperating Archives with Mutual Exchange Agreement
Figure 6-2 is an example of OAIS Archives that have standardized their submission and dissemination methods for the benefit of users. No special external element is needed for this. Its disadvantage is that there is no formal mechanism for exchange of Description Information so Consumers must have separate Search Sessions to locate AIPs of interest.
Figure 6-2: Cooperating Archives with Standard Ingest and Access Methods