14.2. Procedure – Creating and editing protocol-level VNC settings

Purpose: 

VNC settings determine the parameters of the connection on the protocol level, including timeout value, and so on. Complete the following procedure to create a new VNC settings profile or edit an existing one:

Warning

Modifying the VNC settings is recommended only to advanced users. Do not modify these settings unless you exactly know what you are doing.

Steps: 

  1. Navigate to VNC Control > Settings and click to create a VNC setting profile. Enter a name for the profile (for example vnc_special).

  2. Click to display the parameters of the connection.

  3. Modify the parameters as needed. The following parameters are available:

    • Idle timeout: Timeout value for the connection in milliseconds. To avoid early timeout, set it to a larger value, for example a week (604800000 milliseconds).

      Warning

      Determining if a connection is idle is based on the network traffic generated by the connection, not the activity of the user. For example, if an application or the taskbar of a graphical desktop displays the time which is updated every minute, it generates network traffic every minute, negating the effects of timeout values greater than one minute and preventing PSM from closing the connection.

    • Enable pre channel check: Select this option to evaluate the connection and channel policies before establishing the server-side connection. That way if the connection is not permitted at all, PSM does not establish the server-side connection.

    • Cipher strength: There are various types of cipher strengths defined in OpenSSL. Cipher strength can be set separately for server-side and client-side connections. The following cipher strength settings are available:

      • High: Permit only the use of ciphers that use more than 128-bit long keys. This setting corresponds to the high encryption cipher suites of OpenSSL.

      • Medium: Permit only the use of ciphers that use at least 128-bit long keys. This setting corresponds to the medium encryption cipher suites of OpenSSL.

      • Low: Permit all ciphers. This setting corresponds to the low encryption cipher suites of OpenSSL.

      • Custom: Cipher strength according to openSSL standard. The default setting for custom is to permit every cipher, preferring stronger ciphers.

    • Enable SSLv3: By default, PSM permits only TLS-encrypted connections. Enable this option to permit using the SSLv3 protocol. Note that the SSLv3 protocol is considered to be insecure.

  4. Click .

  5. Select this settings profile in the VNC settings field of your connections.