LMF structure

The entities within the LMF, as defined in lmf_ccyy.mtt, consist of Messages, Sequences, and Classes.
  • Messages - Business messages are the highest level concept in the LMF. These messages might correspond directly to an equivalent network message, or more often cover a number of different network messages. For instance, the LMF "Transfers" instruction message covers SWIFT MT 202 and MT 210.
  • Sequences - Each LMF message is constructed from a series of sequences, like the ones that are used in SWIFT messages. Each sequence might contain a number of other entities, either classes, or other sequences called subsequences.
  • Classes - Within each sequence, the individual business elements are called classes. Classes represent each actual business data element, such as a reference. Whereas network message formats contain fields, these are not present in the LMF. Instead, the classes represent types of data (for example, flags, indicators, and dates), and the specific data elements are instances of those classes.
    Each class consists of a set of attributes and subfields. The attributes describe how the class is being used. The subfields contain the actual data that is in use (for example, the date value, or the reference value). The attributes consist of:
    • s - Not used.
    • f - Format value. The format value varies from class to class. It is enforced by a restriction list in the type tree. It describes the format of the data that is held in the class, for example DateOnly to represent the SWIFT 98A date format
    • q - Qualifier value. Varies from class to class. Enforced by a restriction list. It contains the qualifier that describes the business meaning of the class.
    • dss - Contains the data source scheme, if used. The data source scheme is a field that is used in SWIFT ISO 15022 messages.