VShell is a secure portal to a server's resources. VShell provides authentication, encryption, and data integrity using the open Secure Shell protocol (SSH2). VShell provides security for remote command shells, TCP/IP port forwarding (data tunneling), or secure file transfer. SSH2 SFTP, SCP, and now FTPS support provide the secure file transfer mechanisms.

Access to server resources through VShell is controlled through the use of Access Control Lists, listings of available users and groups on the servers along with the actual permissions available to them. Some of the access settings supported by VShell that can be applied to users and or groups include:

- Virtual SFTP directories: Multiple individual folders on the server can be identified and represented by "virtual" folders; and access to these virtual folders can then be granted to individual users or groups.

- "Jail" shells can be applied, automatically limiting a user's interactions (shell access or file transfers) to only their home directories

- The VShell capabilities themselves, i.e., shell access, file transfer, or port forwarding, can be assigned or denied by users and groups

For authentication, VShell augments the standard username/password authentication provided by the servers themselves with Kerberos (via a built in GSSAPI), Public Key, X.509 certificate support, and PAM (Pluggable Authentication Module) support on UNIX. An additional key security feature of VShell is its support for administrator defined "triggers," user-defined actions (such as virus scans or the movement of files) that can be configured to execute automatically upon the completion of file transfers (both upload and download triggers are supported), as well as send alerts when certain numbers of failed authentications are reached.

New features in the latest release of the Windows version of the server include:

- Support for FTP over SSL (FTPS) file transfer

- Support for W3C extended log file formats

- Optional sending of log messages to the Windows Event Log

- Support for "RunAs" commands (remotely execute commands as a different user) - Control panel enhancements, including increased size, support for sortable columns on virtual roots, user database, and RunAs commands pages

- Support for an internal user database, manageable through a VShell Control Panel User Database page - The ability to use the "who" command-line utility to disconnect active sessions

- The ability to start and stop the VShell SSH2 and VShell FTPS services from the VShell Control Panel Common page

VShell is available now in versions with or without FTPS support; supporting 2 concurrent users (VShell Administrator, $249), 10 concurrent users (VShell Workgroup, $499), or unlimited users (VShell Enterprise, $799). The FTPS versions are $349, $699, and $999, respectively. Each of the above prices includes 1 year of updates. Custom configurations are also available.

Please note that not all features described in this briefing may be available in all versions of VShell. Visit the VanDyke Web site for further information.