DAMA is a whole family of multiple-access methods for computer networks. The basic premise is you have a central ''master'' node to which a number of ''slave'' nodes connect to to use the network. The master dictates who can transmit and, optionally, for how long. Therefore, there is guaranteed to be (ideally) no collisions anywhere on the network. (In practice, connection requests can collide when used on a bus-topology network. Still, even in this case, the collision rate will be substantially less than a pure [CSMA/CD] network.) 

  

  

 A node can be a DAMA master on one channel, and a slave on another. Indeed, amateur radio Digipeaters (AX.25 digital repeaters) are often configured this way. 

  

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 3) If a node has nothing to transmit when it is polled, its poll priority is reduced (hence, it is polled less often) relative to nodes that ''do'' have packets to transmit. When it finally does have something to transmit, it's poll priority is brought back to normal. In this manner, DAMA can implement crude forms of quality of service as well, as isochronous data streams can be given much higher priorities than variable-bitrate streams. 

  

 4) If a slave node wishes to disconnect, it does so by sending special packets to the master, where-upon it will remove the slave from the poll-list.