Avocent SPC420 User Manual

Page of 432
290        DSView 3 Software Installer/User Guide
Security Property
A fully functional SSH2 (Secure Shell Version 2) Client is built into the Telnet Viewer. The SSH2 
Client is Java-based and provides a secure method for accessing target devices.
The Telnet Viewer provides the following security features:
Strict host key checking
Support ciphers for AES (128-, 192-, 256-bit), Blowfish, Twofish, Cast, 3DES and Arcfour
Diffie-Hellman key exchange support
SSH-RSA key types
Supported for hmac-md5, hmac-sha1, hmac-sha1-96, hmac-md5-96 and hmac-ripemd160
The DSView 3 software will determine whether to create a Telnet or SSH2 connection when you 
start a session with an appliance. A serial connection provides SSH2 serial access to the target 
device from the appliance. Terminal emulation options are supported using both types of 
connections.
The SSH2 client is started when you initiate a session with an appliance port from the DSView 3 
Explorer. The DSView 3 server is contacted, which in turn contacts the target device connected to 
the appliance port and exchanges X.509 certificates with the target device. The target device also 
supplies a session certificate, private key and appliance certificate.
These certificates are then passed back to the SSH2 client, which uses them to determine the SSH2 
host key and the user SSH2 key. The Telnet Viewer will then establish a session with the target 
device (or through the proxy server if there is a proxy server connection). The Telnet Viewer then 
passes the RSA public key from the session certificate when establishing the SSH connection. 
Finally, the virtual terminal window will open using an SSH2 shell over SSH connection.
SSH2 settings may be viewed by clicking on an appliance name in the DSView 3 Explorer and 
selecting Appliance Settings - Sessions - Settings in the side navigation bar to display the Properties 
- Sessions - Settings window.
Opening a Session
A DSView 3 management software Telnet Viewer session is opened using the DSView 3 Explorer 
by clicking on Telnet Session or Serial Session in the Action column of the target device. If the 
target device is attached to an appliance port, Telnet Session will appear. If the target device is 
attached to an appliance that is also attached to a serial device, Serial Session will appear.
NOTE: If multiple connection methods are available, an alternate actions arrow will appear to the right of the 
action. Clicking the alternate action arrow will display a list of other actions, in descending order of priority, which 
may be selected to launch the corresponding window type.
To open a Telnet Viewer session:
In a Units View window containing target devices (see Accessing Units View windows on 
page 106), click 
Telnet Session or Serial Session in the Action field or the Alternate Action menu.