Full duplex mode allows devices to send and receive data simultaneously, improving network performance and reducing congestion, which is critical for VoIP and video conferencing.
Breakdown of Options:
A). A VLAN with 100Mbps speed limits - VLANs segment traffic but limiting speeds to 100Mbps would worsen video performance.
B). An IP helper to direct VoIP traffic - IP helper is used for DHCP relay, not for VoIP optimization.
C). A smaller subnet mask - A smaller subnet reduces IP address availability but does not improve network performance.
D). Full duplex on all user ports - Correct answer. Full duplex eliminates collisions, allowing better VoIP and video performance.
Reference:
CompTIA Network+ (N10-009) Official Study Guide - Domain 2.2: Compare and contrast various networking devices.
IEEE 802.3: Ethernet Full Duplex Operation