Link Manager layer divided into two functions
Piconet management
Security
Managing 2 physical links between Bluetooth devices
Synchronous connection-oriented (SCO) link
Symmetric point-to-point link between a master and a slave
Like a circuit-switched link by using reserved time slots
A master and slave can each have up to 3 simultaneous SCO links.
Asynchronous connectionless (ACL) link
Packet-switched link used for data transmissions (point-to-multipoint)
ACL link is from one master to all slaves participating on the piconet
A piconet support only a single ACL link between one master and up to 7 slaves, and a slave with a SCO link can also have an ACL link