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VCP-DCV Configure and Manage vSphere Networking Practice Question

Which three factors influence the behavior of Network I/O Control (NIOC) when allocating bandwidth to different traffic types? (Choose three.)

⚠ Common exam trap

VCP-DCV often tests NIOC parameters by mixing in physical capacity factors (total bandwidth, number of uplinks), so candidates who confuse aggregate capacity with per-traffic-type allocation parameters pick the wrong options.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

Reservation per traffic type

Network I/O Control (NIOC) allocates bandwidth on a vSphere Standard or Distributed Switch based on three per-traffic-type settings: Reservation (B), which guarantees a minimum bandwidth in Mbps or Gbps that the traffic type can always use; Shares (C), which determine the relative priority for distributing any remaining bandwidth when the link is contended (e.g., High=100, Normal=50, Low=25 per active uplink); and Limit (D), which caps the maximum bandwidth the traffic type may consume. These three parameters together define how NIOC divides and prioritizes bandwidth among traffic types such as vMotion, iSCSI, and VM traffic. The total physical bandwidth (A) is not a configurable NIOC factor — it is the underlying capacity that reservations, shares, and limits act upon, and NIOC itself does not let you set it. The number of physical uplinks (E) affects aggregate capacity and teaming behavior, but NIOC allocation is driven by the per-traffic-type reservation, shares, and limit values, not by the uplink count.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✗
The total physical bandwidth
Why it's wrong here
Total physical bandwidth sets the ceiling, but NIOC shares are calculated as ratios of the bandwidth available to a given traffic type, so this alone does not determine allocation behaviour. It is tempting because capacity obviously bounds throughput, and it matters when sizing uplinks rather than configuring shares.
✓
Reservation per traffic type
Why this is correct
Reservations guarantee a minimum bandwidth share for each traffic type, so NIOC honours them before distributing any remaining capacity. This directly satisfies the stem's allocation behaviour: a traffic type with a reservation cannot be starved by busier flows, even when shares and limits would otherwise favour competing traffic.
✓
Shares per traffic type
Why this is correct
Shares set the relative priority each traffic type receives when contention occurs, determining proportional bandwidth distribution under NIOC. Higher shares grant a traffic type a larger slice of available capacity, directly influencing allocation behaviour during congestion.
✓
Limit per traffic type
Why this is correct
The limit per traffic type caps the maximum bandwidth a given traffic type may consume, directly shaping NIOC allocation alongside shares and reservations. It constrains burst usage so one traffic type cannot starve others during contention.
✗
The number of physical uplinks
Why it's wrong here
NIOC allocates bandwidth as a proportion of the capacity available to each traffic type, not by counting uplinks; adding uplinks changes aggregate capacity, not the share ratios. It is tempting because more uplinks clearly raise throughput, and it is relevant when designing teaming and failover.

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VCP-DCV Configure and Manage vSphere Networking Practice Question

Why each option matters

Option-by-option breakdown

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