The E-POSTBRIEF is an electronic letter service provided by Deutsche Post that allows secure and reliable digital communication between businesses and individuals. It is part of Europe's largest business-to-business network run by SAP and Crossgate, which provides a platform for electronic exchange of information between a company's SAP software and its customers and suppliers. The network connects SAP systems directly or via the SAP Information Interchange web portal to enable integrated e-business processes across organizations.