An ANT channel is between the master and slave endpoint. The master endpoint is always transmitting (the primary transmitter). As mentioned earlier, ANT is mostly used as an isochronous network protocol. A decision to manage the trade off between data latency and battery life must be made. At this point the predominant variable in this decision is the number of messages sent from master to the slave per second. In ANT talk this is known as the channel period, which ANT allows to be configured very finely between 0.5-200Hz. Each message is comprised of a small overhead and eight bytes of user defined data. Messages are clocked over the air at 1MHz  and each message uses the radio for only 150µS.