The PACS of an image management and communications system (IMACS) must have a communications infrastructure that supports not just the transmission of images, but the transmission of images with minimal latency while utilizing the bandwidths available in emerging high-speed networks that provide transfer rates between 100 Mbps and 2.3 Gbps. At the Bowman Gray School of Medicine, the ACR/NEMA Digital Imaging and Communication (DICOM) Document has been modified to use standard networks and protocols in lieu of the lower layers of the ACR/NEMA document, providing valuable insight into the use of the ACR/NEMA upper layers. This paper compares the performance of three communications mechanisms that use TCP/IP and XTP for data transport. The first application uses a communication paradigm that has been proposed for the new version of ACR/NEMA. Even though DICOM version 3 does not support the emerging high-performance protocols, XTP is also used in this mechanism. The other two applications employ a communication paradigm used by PAPYRUS, in which the actual transfer syntax (often called ''ACR/NEMA logical'') is used with standard network protocols that move data within application programs. One utilizes transfers from an application program, and the other uses standard file system transfers.