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README.md

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-# CF
+# CCSDS File Delivery Protocol
+
+NASA core Flight System File Transfer Application
+
+## Description
+
+The CCSDS File Delivery Protocol (CFDP) application (CF) is a core Flight System (cFS) application that is a plug in to the Core Flight Executive (cFE) component of the cFS.
+
+The cFS is a platform and project independent reusable software framework and set of reusable applications developed by NASA Goddard Space Flight Center. This framework is used as the basis for the flight software for satellite data systems and instruments, but can be used on other embedded systems. More information on the cFS can be found at [http://cfs.gsfc.nasa.gov](http://cfs.gsfc.nasa.gov)
+
+The CF application is used for transmitting and receiving files. To transfer files using CFDP, the CF application must communicate with a CFDP compliant peer.
+
+CF sends and receives file information and file-data in Protocol Data Units (PDUs) that are compliant with the CFDP standard protocol defined in the CCSDS 727.0-B-4 Blue Book. The PDUs are transferred to and from the CF application via CCSDS packets on the cFE's software bus middleware.