Which of the following statements describe the primary objectives of the policing of traffic flows on the Alcatel-Lucent 7750 SR? (Choose two)

Question

Options

• AEnsure that traffic flows conform to their traffic profile.
• BLog violations of metered traffic flows exceeding the CIR value set on the entity across which the
• CProvide fairness between traffic flows, so that conforming (in-profile) traffic flows are not starved
• DMinimize packet loss and reduce end to end latency.
• EEnsure that variable latencies do not cluster short bursts of originally conforming packets and

• A
  74% (17)
• B
  4% (1)
• D
  13% (3)
• E
  9% (2)

Explanation

Traffic policing on the 7750 SR serves two core purposes: enforcing conformance (A) and protecting well-behaved flows (C). Option A is correct because policing's fundamental job is to measure traffic against a defined profile (using CIR/PIR token buckets) and drop or re-mark packets that exceed it - that's the definition of policing. Option C is correct because by discarding or downgrading out-of-profile traffic, the policer guarantees that conforming, in-profile flows aren't starved of their entitled bandwidth by greedy flows.

Why the distractors are wrong:

• B - Logging violations is a monitoring/accounting function, not a policing objective; policers act on traffic, they don't record it.
• D - Minimizing packet loss and reducing latency are goals of scheduling and queuing, not policing; in fact, policing deliberately increases packet loss for non-conforming traffic.
• E - Smoothing out burst clustering caused by variable delay is the job of traffic shaping (which buffers and paces packets), not policing (which simply drops or re-marks).

Memory tip: Think of a policer as a strict bouncer, not a traffic engineer - it checks IDs (conforms to profile?) and turns away violators (A), ensuring the people already inside aren't crowded out (C). It doesn't keep a guestbook (B), unclog the road outside (D), or space out arrivals evenly (E - that's the shaper's job).

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