The AIXM UML model includes basic constraints expressed as lists of values, range of values, patterns. These are enforced in the AIXM XML Schema. More complex constraints, such as dependencies between the values of different attributes (sometimes in different classes), detection of out of range values, mandatory properties for specific data usage, data quality requirements (resolution, accuracy), etc. are not included in the UML model and do not appear in the XML Schema. Thus the need to document such more complex constraints as “business rules”.
In the earlier versions (up to AIXM 4.5), such business rules were part of the model. However, the experience accumulated through implementation shows that such rules are not equally applicable in all AIXM communities. The most obvious example are mandatory properties for AIXM features. For flight planning applications, there is no need for the frequency/channel of a navigation aid. On the other side, such attributes are mandatory for data sets intended for air navigation applications. Therefore, the aim of the AIXM Business Rules project is to maintain an exhaustive set of candidate AIXM business rules, from which profiles for a particular application or set of applications can be extracted.
The Semantics of Business Vocabulary and Rules (>>> SBVR) standard is used for the writing of the AIXM business rules in relation with the AIXM UML logical data model, which provides the "business vocabulary". The following document describes the concepts and conventions applied in the writing of the AIXM business rules:
► AIXM Business Rules - Using SBVR
AIXM Business Rules versions
The most recent release of the AIXM Business Rules is version 0.9.0 and it is provided through the link below. This version contains the rules that are used by the European AIS Database (EAD), Release 15.1 (scheduled for deployment in June 2023) for AIXM 5.1 data providers.
► AIXM 5.1 - Business Rules - version 0.9.0
Note: Each set of business rules is applicable to a specific AIXM version and each rule has a unique identifier that includes the AIXM version. The current set is applicable to AIXM version 5.1. However, the same rules can be used with AIXM version 5.1.1, as there are no differences between the two AIXM versions that would make one of the rules inapplicable.
The next version is scheduled for the first part of 2023 and it will include some additional changes in the rules for EAD, scheduled for implementation in Release 15.2
For information, previous working versions of the AIXM 5.1 Business Rules set are provided here:
► [2022/01] AIXM 5.1 - Business Rules - version 0.8.5
► [2019/02] AIXM 5.1 - Business Rules - version 0.8
► [2017/02] AIXM 5.1 - Business Rules (ver. 0.7.2)
► [2015/09] AIXM 5.1 - Business Rules (ver. 0.5)
► [2015/06] The second draft set published under the new SBVR project (ver 0.4)
►  The first draft set of rules published under the new SBVR project (ver. 0.3)