NBEMS is the only application that would meet your DEC's requirements, find it within the latest implementing of FLDIGI. It contains ARQ PSK31, ARQ MFSK16 and a few other modes. Also facilitates email exchanges on a point to point basis with the ability to drop email off in to the Internet. It is all free.
Then, in a few weeks time (maybe couple of months) expect Winmor to be added to the Winkink system. Winkink currently handles files and email via packet radio and Pactor. Pactor II and Pactor III require expensive TNC's but Winmor will allow sound card digital applications to connect to a "server" on HF. Thus, with NBEMS you have a very easy system of point to point error correcting communication. With Winmor and Packet in Winlink , you have the ability to do everything else. The two combined will be about as elaborate as hams can get, ALE systems notwithstanding. Andy K3UK
