VNC User Guide
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Principles of VNC remote control
Getting the computers ready to use
Connectivity and feature matrix
Step 1: Ensure VNC Server is running on the host computer
Step 2: Start VNC Viewer on the client computer
Step 3: Identify VNC Server running on the host computer
Step 4: Request an encrypted connection
Configuring VNC Viewer before you connect
The VNC Viewer user experience
Using the VNC Viewer - Options dialog
Managing the current connection
Changing appearance and behavior
Restricting access to features
Chapter 4: Connecting From A Web Browser
The VNC Viewer for Java user experience
Working with VNC Viewer for Java
Chapter 5: Exchanging Information
Printing host computer files to a local printer
Transfering files between client and host computers
Copying and pasting text between client and host computers
Communicating securely using chat
Chapter 6: Setting Up VNC Server
Running multiple instances of VNC Server
Preventing connections to VNC Server
Restricting functionality for connected users
Chapter 7: Making Connections Secure
Authenticating connections to VNC Server
Relaxing the authentication rules
Bypassing the authentication rules
Preventing particular connections to VNC Server
Restricting features for particular connected users
Uniquely identifying VNC Server
Appendix A: Saving Connections
Saving connections to VNC Address Book
Using VNC Address Book to connect
By default, VNC Server listens for connections on a particular port. In addition, VNC Server (Enterprise) and VNC Server (Personal) listen for VNC Viewer for Java download requests on a different port. You can change these ports, or make them the same.
Note: VNC Server (Free) does not listen for VNC Viewer for Java download requests. Upgrade the host computer to VNC Server (Enterprise) or VNC Server (Personal) if this feature is important to you.
By default, two separate ports are assigned when VNC Server starts, one for connections and one for download requests:
• Under Windows and Mac OS X, VNC Server in both Service Mode and User Mode is assigned port 5900 for connections and port 5800 for download requests.
• Under UNIX/Linux, VNC Server in:
— User Mode is assigned port 5900 for connections and port 5800 for download requests.
— The first instance of VNC Server in Virtual Mode is assigned port 5901 for connections and port 5801 for download requests. Subsequent instances of VNC Server in Virtual Mode are assigned port numbers incremented by one, where possible, for example 5902, 5903 (and 5802, 5803), and so on, up to the maximum number of desktops permitted by the host computer’s license.
Note: For more information about running multiple instances of VNC Server, and the different modes, see Running multiple instances of VNC Server.
If more than one instance of VNC Server is running on a host computer, they must all listen on different ports; see below for information on resolving port conflicts. Note, however, that a particular instance of VNC Server can listen on the same port for connections and download requests; see Making the connection and download port the same for more information.
Note: When connecting to VNC Server, a user must qualify the host computer’s network address with the port number in all cases except when VNC Server is listening for connections on port 5900 only. For more information, see Qualifying a network address with a port number.
VNC Server must listen for connections and for VNC Viewer for Java download requests on a unique port. This is one on which no other instance of VNC Server, nor any other program or service, is listening.
Port conflicts disable VNC Server. You should be able to resolve them by changing ports on the Connections tab of the VNC Server - Options dialog. More on this dialog.
Changing the connection port
You can change the port on which VNC Server is listening for connections. If you do this:
• Users need to know the new port number (if it is not 5900) in order to connect. For more information, see Qualifying a network address with a port number.
• If the host computer is protected by a firewall, then the firewall must be configured to allow incoming network communications to the new port. For more information, see Allowing network communications through a firewall.
• If the host computer is protected by a router and users are connecting over the Internet, then the router must be configured to forward communications to the new port. For more information, see Configuring a router to forward network communications.
To change the port, enter a different number in the Accept connections on port field. Note that changing this option does not affect currently connected users.
Changing the download port
You can change the port on which VNC Server is listening for VNC Viewer for Java download requests. If you do this:
• Web browser users need to know the new port number in order to download. For more information, see Qualifying a network address with a port number.
• If the host computer is protected by a firewall, then the firewall must be configured to allow incoming network communications to the new port. For more information, see Allowing network communications through a firewall.
• If the host computer is protected by a router and web browser users will connect over the Internet, then the router must be configured to forward communications to the new port. For more information, see Configuring a router to forward network communications.
To change the port, enter a different number in the Serve Java viewer on port field. Note that changing these options does not affect currently connected users.
Making the connection and download port the same
VNC Server can listen on the same port for connections and download requests. This may simplify firewall configuration and make the host computer more secure.
To use the same port, enter the same number in the Accept connections on port and Serve Java viewer on port fields. Note that configuring these options does not affect currently connected users.
