● Both bus and tree topologies are characterized by the use of multipoint （71）. For the bus, all stations attach, through appropriate hardware（72）known as a tap, directly to a linear transmission medium, or bus. Full-duplex operation between the station and the tap allows data to be transmitted onto the bus and received from the （73）. A transmission from any station propagates the length of the medium in both directions and can be received by all other （74）.At each end of the bus is a （75) , which absorbs any signal, removing it from the bus.
（71）
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