DMX -> USB PC interfaces such as the ENTTEC and DMXKing DMX USB Pro with public API and other DIY, and free or Open source software hardware combinations are available. Many console vendors also make a software simulator or "offline editor" for their hardware consoles, and these are often downloadable for free. The simulator can be used to pre-program a show, and the cues then loaded into the actual console. In addition, lighting visualization software is available to simulate and approximate how lighting will appear on stage, and this can be useful for programming effects and spotting obvious programming errors such as incorrect colour changes. Remote focus unit Many memory consoles have an optional Remote Focus Unit (RFU) controller that can be attached to the light board and used to control the board's functions (though usually in some limited capacity). They are usually small enough to be handheld. This is ideal in situations where moving the light board is impractical, but control is needed away from where the board is located. That is, if the light board is in a control room that is located far from the fixtures, such as a catwalk, an RFU can be attached and an electrician or the lighting designer can bring it to a location which is close to the lights. Some of the newer and more advanced boards have RFUs that can be connected through USB or even wirelessly. Various manufacturers offer software for devices such as Android and iPhones that cause the devices to act as remote controllers for their consoles. Also, independent software developers have released applications that can send Art-Net packets from an iPhone, thus enabling an iPhone to serve as a fully featured console when used in conjunction with an Art-Net to DMX converter or Art-Net compatible luminaries and dimmers. An example of this is ETC's (electronic theater controls) app called iRFR for Apple devices or aRFR for Android devices. The Controller Interface Transport Protocol, or CITP, is a network protocol used between visualizers, lighting control consoles and media servers to transport non-show critical information during pre-production. The protocol is used for a number of purposes including SDMX, browsing media and thumbnails, and streaming media among different devices. See also Avolites Compulite Frederick Bentham Genlyte Group George Izenour Light board operator, the person working the lightboard. Lighting control systems for a building or residence. Non-dim circuit Strand Lighting References