ascp4: Transferring from the Command Line with Ascp 4 Ascp 4 is a FASP transfer binary similar to Ascp but it has different strengths as well as capabilities that are unavailable with Ascp. Introduction to Ascp 4 Ascp 4 is a FASP transfer binary that is optimized for sending extremely large sets of individual files. The executable, ascp4, is similar to ascp and shares many of the same options and capabilities, in addition to data streaming capabilities. Ascp 4 Command Reference Supported environment variables, the general syntax, and command options for ascp4 are described in the following sections. ascp4 exits with a 0 on success or a 1 on error. The error code is logged in the ascp4 log file. Ascp 4 Transfers with Object Storage Files that are transferred with object storage are sent in chunks through the Aspera Trapd service. By default, ascp4 uses 64 KB chunks and Trapd uses 1 MB chunks; this mismatch in chunk size can cause ascp4 transfers to fail. Ascp 4 Examples