The Federal Railroad Administration contracted Transportation Technology Center, Inc. to define Interface Requirement Specification (IRS) documents for an Interoperable Train Control Automated Train Operation Support System Back Office (ITC-ATOSS BO). This project forms part of a larger Automated Train Operation (ATO) effort in cooperation with the North American railroad industry. The IRS documents define interoperable interfaces between the following:

Interoperable Train Control Automated Train Operation Executive (ITC-ATO Ex) subsystem and ITC-ATOSS BO
ITC-ATOSS BO and Interoperable Train Control Positive Train Control Back Office (ITC-PTC BO)
The goal of the ATO effort is to produce interoperable standards which allow an ATO train developed by any railroad to operate on any railroad’s territory when equipped with the necessary infrastructure and supported by any railroad’s qualified personnel. For an ATO train to be interoperable, it must communicate with each railroad’s ITC-ATOSS BO using a standardized interface. The details of this interface are defined by an IRS.