Ref2disk, developed at the University of Utah, collects Reftech formatted data from a UNR Reftek Data Server, a disk file, or an Earthworm transport ring. The data (DT) packets are forwarded to the Earthworm transport layer as TRACE_BUF format messages and optionally written to disk as binary SAC files. In addition, the Reftech channel packets are saved on disk and their contents decoded and used to update the SAC file headers.