Synchronization bits areused for synchronization of transmissions on nets and buses, for synchronous
triggering of events, displays or for synchronization of
clocks. In synchronous transmissions, synchronization bits are used to establish synchronization between the sender and receiver. In asynchronous transmissions, where the tect generators are not synchronously clocked by the transmitting and receiving data transmission equipment, the synchronous bits are transmitted before the user data in each case. In character-oriented protocols of the data link layer, they are used for block synchronization.