RIPEM is a program developed by Mark Riordan that enables secure Internet e-mail; it provides both encryption and digital signatures, using RSA and DES routines from RSAREF (see Question 3.8.10). RIPEM is not fully PEM-compatible; for example, it does not currently support certificates. However, future versions will include certificates and will be fully compliant with the PEM standard. RIPEM is available free for non-commercial use in the U.S. and Canada. To get RIPEM, obtain an ftp account at ripem.msu.edu.