The VNC protocol

The VNC protocol

The VNC system is based on the concept of a remote framebuffer or RFB. We therefore often refer to the protocol underlying VNC as the RFB protocol.

The protocol specification (Acrobat format)
The header file rfbproto.h which is used by the system.(Acrobat format)

Additional encodings

Various people have developed their own encodings for VNC. These new encodings shouldn't break compatibility with other VNC servers and viewers, since a server can always ignore a request for an encoding, and a viewer never gets sent an encoding it doesn't request. However it's important that people don't use the same encoding number for different purposes. Here is a list of the encoding numbers which we know people are using. If you come up with a new encoding let us know and we'll add it to the list.

0 to 5 are standard RFB 3.3 encodings.
6 is used by Dave DeBarr's zlib encoding, and also by Tridia's zlib encoding.
7 is Const Kaplinsky's tight encoding.
8 is the zlib hextile encoding used by Tridia and VNCThing
0xFFFFFF00 to 0xFFFFFFFF are currently being used for various pseudo-encodings, by Const Kaplinsky and Tridia. These may be still evolving, but this range is best avoided for any other purpose.

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