ISC Exam Questions

What technique is used to prevent eavesdropping of digital cellular telephone conversations?

What technique is used to prevent eavesdropping of digital cellular telephone conversations?

A.
Encryption

B.
Authentication

C.
Call detail suppression

D.
Time-division multiplexing

Explanation:
The name “TDMA”( Time Division Multiple Access) is also used to refer to a specific
second generation mobile phone standard – more properly referred to as IS-136, which uses the
TDMA technique to timeshare the bandwidth of the carrier wave. It provides between 3 to 6 times
the capacity of its predecessor AMPS, and also improved security and privacy. In the United
States, for example, AT&T Wireless uses the IS-136 TDMA standard. Prior to the introduction of
IS-136, there was another TDMA North American digital cellular standard called IS-54(which was
also referred to just as “TDMA”).