300-420 Question 255
Single answerA network engineer is tasked with implementing traffic policing on a Cisco enterprise network to ensure that specific traffic does not exceed a defined bandwidth limit. The engineer configures policing on an interface for a VoIP traffic class with the goal of dropping excess traffic beyond the configured rate. Which of the following actions should be configured to meet this requirement?
- A
Configure the 'police' command with the 'conform-action transmit' and 'exceed-action drop' options.
- B
Use the 'shape average' command to limit traffic to the configured rate.
- C
Apply the 'police' command with the 'conform-action transmit' and 'exceed-action transmit' options.
- D
Deploy the 'police' command with the 'conform-action transmit', 'exceed-action drop', and 'violate-action drop' options.
Show answer and explanation
Correct answer: A
Explanation
Policing is used to enforce bandwidth limits by dropping or remarking traffic exceeding the configured rate. In this scenario, the requirement is to drop excess traffic beyond the configured rate, which can be achieved by configuring the 'police' command with 'conform-action transmit' (to allow conforming traffic) and 'exceed-action drop' (to drop excess traffic). Other options either use incorrect mechanisms like traffic shaping or fail to meet the requirement to drop excess traffic.
- A. Correct.
This option is correct because it configures the police command to transmit traffic within the conforming rate and drop traffic that exceeds the rate, which aligns with the scenario's requirement.
- B. Incorrect.
This option is incorrect because traffic shaping ('shape average') buffers excess traffic instead of dropping it, which does not meet the requirement to drop excess traffic.
- C. Incorrect.
This option is incorrect because configuring 'exceed-action transmit' would allow traffic exceeding the rate to pass through, violating the specified requirement.
- D. Incorrect.
This option is not the best choice because while it drops traffic exceeding and violating the rate, the scenario only specifies handling excess traffic, not violating traffic.