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## 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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