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SIP Model is an abstract model that has to be followed by any PAIS compliant SIP.
Source:Consultative Committee on Space Data Systems. Producer-Archive Interface Specification (PAIS) - A Tutorial. Report Concerning Space Data System Standards, CCSDS 651.2-G-1. Green Book. Issue 1. Washington, D.C.: CCSDS, September 2016. [Equivalent to ISO 20104:2015]
Introduction
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PAIS provides an abstract SIP Specification (CCSD0017) known as the SIP Model. The SIP Model puts constraints on all possible SIPs within a given Producer-Archive Project.
Section 5 of PAIS explains:
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There are two methods by which a Producer-Archive Project can achieve SIPs that conform to the PAIS SIP Model:
Adopt the PAIS SIP Model XML schema based on the XFDU packaging standardOther (available in the Data Archive Ingest XML repository)
Create a specialized SIP Model based on other packaging mechanisms (e.g., the BagIt specification)
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As noted in Section 6.2.4 of the PAIS Tutorial:
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