This page contains technical data & information mainly for developers of computer software that interface with USA Swimming data/computer systems. 

USA Swimming has matured as an organization and expanded services to individuals and clubs. To support this expansion, USAS has developed a computer plan. One component is a standard interchange format for technical data. Swimming data is be transmitted among the clubs, Local Swimming Committees (LSCs), and the USAS headquarters office. Exchanging meet results is one example, where data from a host club is distributed to LSCs and clubs using diskettes or modems. Some LSCs are compile swimmer statistics and currently retype the data from printed sheets if electronic transmission is not available. A standard format promotes easy exchange of data and the development of new computer programs and services. The goal is to preserve the valuable efforts of our volunteers.

This specification is based upon the original SDIF v3.0 data interchange format. The new XSDIF format addresses the limitations of SDIF in several ways. First the format has been transformed from using fixed column text files to using XML. XML is being adopted all across the computer industry as the best way to transmit data between systems. There are many reasons for the rapid adoption of XML some of the more important are:

• XML is plain text so that it can be read on any computer system.
• XML is self-documenting so that a human can open an XML file and have some idea of what data the document contains.
• XML is extensible.
• It is easy to write programs to read and write XML
• It is easy to validate XML documents using off-the-shelf software.
• XML document structures and data types can be formally defined using XMLSchema language.

The format incorporates a modular design. Each file would combine the records into an order that corresponds to the type of data to be transmitted. Meet entry records have a specific order. Time standards have another order. When specific record types are not needed, those records can be omitted.  Certain fields were declared to be "mandatory" for adequate identification of the data and to preserve unique identifiers.

This specification is provided as an XML schema. This schema uses XML to define what data is required and legal in an XSDIF file. This document is written assuming that the reader is familiar with XML terminology. If you are not familiar with XML terminology, there are many excellent books available. Some suggestions are Professional XML Schemas by Duckett et al from Wrox Press or Professional XML 2nd Edition by Pinnock et al also from Wrox Press.

The above information is taken from the XDIF Specification Document.