Transmission of information in a communications link is defined by three protocol techniques: half duplex, full duplex, and __________.
A. asynchronous
B. framing
C. simplex
D. synchronous
Question 2
What is the primary function of the private branch exchange (PBX)?
A. Switching one telephone line to another
B. To meet the increasing demands of data transmission
C. To meet the economic objectives of providing service
D. To maintain order during the interchange of data