VShell Server is a secure access server for Windows NT, 2000, and 2003, Red Hat Linux, Sun Solaris, HP-UX, Mac OS X, AIX, and FreeBSD, supporting the Secure Shell protocol (SSH2). VShell can be used for secure network access, system administration, and file transfer. In conjunction with an SSH2 client such as SecureCRT, VShell provides an encrypted session that includes a command shell and TCP/IP data tunneling using port forwarding. SFTP and SCP support allows secure FTP applications, such as SecureFX, to connect for secure file transfers. System administrators can use any SSH2 client, such as SecureCRT or Linux and Unix clients, to access the server PC through the secure command shell. Using NT and DOS utilities, you can start and stop the server, add and remove users, copy files, and even reboot the machine. VShell 2.3.1 adds virtual root directories for UNIX, support for PAM SecurID and PAM Password authentication, and a new vsftp interactive command-line file transfer client.