Which VoIP components can permit or deny a call attempt on the basis of a network’s available bandwidth?

A.
MCU

B.
Gatekeeper

C.
Application server

D.
Gateway

Explanation:
Gatekeepers can be thought of as the traffic cops of the WAN. For example, because bandwidth on a WAN typically is
somewhat limited, a gatekeeper can monitor the available bandwidth. Then, when there is not enough bandwidth to
support another voice call, the gatekeeper can deny future call attempts.
A) MCU: Multipoint Control Unit
MCUs are useful for conference calling. In a conference call, you might have multiple people talking at the same time,
and everyone on that conference call can hear them. It takes processing power to mix together these audio streams.
MCUs provide that processing power. MCUs might contain digital signal processors (DSP), which are dedicated pieces
of computer circuitry that can mix together those audio streams.
D) A gateway in CISCO networking concept does not have anything to do with bandwidth monitoring.
C) Application Server – possibly be but not in this context.