The GAP defines how devices interact with each other to ensure device interoperability. It defines how Bluetooth LE devices discover each other, establish secure connections, terminate connections, broadcast data and device configuration. This is the lowest level of the Bluetooth LE stack that we will cover in this chapter.
Earlier in this chapter, we saw that a Bluetooth LE device could be in one of two states. In the broadcasting topology, a device can be either the broadcaster (slave) or observer (master). If a connection between the two devices is established, then the devices become either a central (master) or peripheral (slave). We introduced the terms master and slave here to illustrate the states that ...
