Which two of these are differences between traffic policing and traffic shaping? (Choose two.)

A.
with traffic shaping, a router stores excess traffic in packet buffers until bandwidth is available
again

B.
with policing you can tune the buffer usage for traffic exceeding the specified CIR

C.
with shaping you can tune the buffer usage for traffic exceeding the specified CIR

D.
shaping should only be applied for ingress traffic, policing only for egress

E.
policing uses a token bucket algorithm, shaping uses an SPD algorithm

Explanation:
Traffic policing propagates bursts. When the traffic rate reaches the configured maximum rate,
excess traffic is dropped (or remarked). The result is an output rate that appears as a saw-tooth
with crests and troughs. In contrast to policing, traffic shaping retains excess packets in a queue
and then schedules the excess for later transmission over increments of time. The result of traffic
shaping is a smoothed packet output rate. Shaping implies the existence of a queue and of
sufficient memory to buffer delayed packets, while policing does not. Queueing is an outbound
concept; packets going out an interface get queued and can be shaped. Only policing can be
applied to inbound traffic on an interface. Ensure that you have sufficient memory when enabling
shaping. In addition, shaping requires a scheduling function for later transmission of any delayed
packets. This scheduling function allows you to organize the shaping queue into different queues.
Note: in particular that the term CIR refers to the traffic rate for a VC based on a business contract,
and shaping rate refers to the rate configured for a shaper on a router.