Which Layer 2 protocol encapsulation type supports synchronous and asynchronous circuits and
has built-in security mechanisms?
A.
HDLC
B.
PPP
C.
X.25
D.
Frame Relay
Which Layer 2 protocol encapsulation type supports synchronous and asynchronous circuits and has built-in security mechanisms?
Which Layer 2 protocol encapsulation type supports synchronous and asynchronous circuits and
has built-in security mechanisms?
PPP supports both synchronous (like analog phone lines) and asynchronous circuits (such as ISDN or digital links). With synchronous circuits we need to use clock rate.
Note: Serial links can be synchronous or asynchronous. Asynchronous connections used to be only available on low-speed (<2MB) serial interfaces, but now, there are the new HWICs (High-Speed WAN Interface Cards) which also support asynchronous mode. To learn more about them please visit
PPP also has built in security mechanisms such as PAP and CHAP