Answer
The products most often meant by the term are TL2000, carrier dispatch and operations software built on the IBM System i and now owned by Trimble; the Innovative Computing line including Access Plus, acquired by TMW Systems in 2009 along with roughly 300 IBM i customers; TMT Fleet Maintenance for work orders, preventive maintenance and parts; ShipSoft Parcel and ShipSoft Freight from Varsity Logistics for multi-carrier parcel, LTL, truckload and rail rating; and the AR Traffic suite for freight rating, routing, bid analysis and audit. What they have in common is that the transportation business logic lives on the same machine as the rest of the company's transaction data, which is exactly why replacing it is harder than it looks in a demo.