Oppo-Flood: An Energy-Efficient Data Dissemination Protocol for Asynchronous Duty-Cycled Wireless Sensor Networks

Figure 1

Behavior of BoX-MAC. Node A has a packet to send to B so it wakes up and sends the packet repeatedly. When node B wakes up according to its schedule, it receives the packet and sends an ACK to node A. On receiving the ACK, node A stops transmission and goes back to sleep. Node D wakes up before node A starts transmitting, so it goes back to sleep after checking the channel. Node C wakes up and starts receiving the packet, but later finds the packet to be invalid (not to be received) and goes back to sleep.