...

The data structure of each type of XML document in eLandings is unique, but the documents share some common features.

Schema Version

The eLandings XML documents include a schema version number that tells receiving systems what version of the schema was used in preparing the document. This allows receiving systems to appropriately downgrade documents if a newer schema is in use.

Messages

Most eLandings XML document include a messages section that contains messages about the actions of web services that created or processed the document.

Report Data

The various XML documents contain data appropriate to their type and function, for example landing report and fish ticket data in landing report documents and NMFS production report data in production report documents.

XML Schema

The XML schema is used to describe the format of XML documents in eLandings. Since the format can be enhanced over time the XML schema includes a version number that uniquely identifies that version of the schema, and that can be used to communicate to the system the version of the schema that was used to create any particular landing report file or XML document.

...

Whenever the eLandings developers need to add a data element they modify the XML schema. They also increment the schema version number, and modify the eLandings codebase to add forward and backward compatibility logic to handle differences in documents made with different versions of the schema.

XML Usage Documentation

The eLandings documentation on the Confluence website includes a system interface guide that describes