By definition, how many keys are needed to lock and unlock data using symmetric-key encryption?
A.
3+
B.
2
C.
1
D.
0
Explanation:
Symmetrical Keys present a difficult challenge to both a key management and a security perspective. The loss or compromise of a symmetrical key compromises the entire system. Single key systems are entirely dependant on the privacy of the key. This key requires special handling and security. Make sure that symmetrical keys are never divulged. Symmetrical keys should be transmitted using secure out-of band methods.
Reference: Security + (SYBEX) page 385-386