The US Army Contracting Command - Aberdeen Proving Ground (ACC-APG) required InfoVista Software. This request was for a modification to the existing contract/order which was a Firm-Fixed-Price (FFP) d... The US Army Contracting Command - Aberdeen Proving Ground (ACC-APG) required InfoVista Software. This request was for a modification to the existing contract/order which was a Firm-Fixed-Price (FFP) delivery order under the Computer Hardware Enterprise Software and Solutions (CHESS), Indefinite-Delivery Indefinite-Quantity contract.