Hi Opher
Welcome to TM Forum!
GB stands for Guide Book. GB922 is a series of documents that are published as part of the Information Framework (the SID) along with the formal UML model. The guide books add examples, descriptive text, use cases, and more.
The data model used in the Open APIs is derived (eventually) from the SID, so an understanding of the SID can contribute as a background to learning Open APIs, although not essential.
Hope it helps!
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Jonathan Goldberg
Amdocs Management Limited
Any opinions and statements made by me on this forum are purely personal, and do not necessarily reflect the position of the TM Forum or my employer.
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