vncviewer

Launch a VNC client which connects to a host on a given display

$ vncviewer [host]:[display_number]

$ vncviewer -FullScreen [host]:[display_number]

$ vncviewer --geometry [width]x[height] [host]:[display_number]

$ vncviewer [host]::[port]

vncviewer [options] [host][:displaynumber]

-Via gateway
    Connect to the VNC server via the specified gateway using SSH tunneling. gateway is specified in the form user@host:port.

[host][:displaynumber]
    Specifies the host and display number of the VNC server to connect to. If displaynumber is omitted, it defaults to 0.

-passwd file
    Specifies a file containing the VNC password.

-FullScreen
    Start the viewer in FullScreen mode.

-ViewOnly
    Connect in view-only mode (no keyboard or mouse input sent).

-Shared
    Request shared access to the VNC server (allow multiple viewers).

-geometry WxH
    Specifies the initial window size in pixels.

-Log filename
    Specifies log file name.

-Quality level
    Set the image quality level (0-9, 0 is best quality and 9 is lowest.

-CompressLevel level
    Set the compression level(0-9, 0 is no compression and 9 is best compression.

vncviewer is a client program used to connect to a VNC (Virtual Network Computing) server, allowing you to view and control a remote computer's desktop environment. It facilitates graphical remote access, enabling users to interact with applications, files, and the operating system on the remote machine as if they were physically present.

VNC operates on a client-server architecture. The VNC server runs on the machine you want to control, sharing its screen and accepting input. The vncviewer then connects to this server, receiving screen updates and forwarding keyboard and mouse events. VNC is commonly used for remote administration, technical support, and accessing resources on distant systems.

Different VNC server implementations exist (e.g., TigerVNC, TightVNC, RealVNC), and vncviewer is typically compatible with a variety of these servers. The precise features and options available may vary depending on the specific VNC implementation and version. Security considerations are paramount when using VNC over a network, especially the internet, and proper encryption is crucial. SSH tunneling or other security measures are often employed to protect VNC connections.

VNC connections, by default, are unencrypted. Therefore, it's essential to use a secure tunnel (like SSH) or a VNC server implementation that supports encryption to protect sensitive data during transmission. Ensure the VNC server is properly configured and secured to prevent unauthorized access. Firewall rules may need to be adjusted to allow VNC traffic.

Always prioritize security when using vncviewer. Use SSH tunneling (the -Via option) or a VNC server with built-in encryption to protect the VNC connection from eavesdropping. Employ strong passwords for VNC server authentication.

VNC performance can be affected by network latency and bandwidth. Adjusting the image quality (-Quality) and compression level (-CompressLevel) can help optimize performance based on the network conditions. For slower connections, lower quality and higher compression are usually preferable.

VNC was originally developed at Olivetti Research Laboratory in the UK. The initial versions were open source, leading to the development of various VNC implementations like TightVNC, TigerVNC, and RealVNC. vncviewer is the client-side component that has evolved alongside the server implementations. The core concept remains consistent - providing remote graphical access - but features like security, performance, and platform support have been enhanced over time.

vncserver(1), ssh(1)