A well-designed IP addressing scheme supporting role-based functions within the subnet will result in the most efficient use of which technology?

Layer 3 core switching efficiency is improved through route summarization and topology design, not specifically through role-based IP addressing within subnets.

NAC enforces admission based on identity, posture, and policy regardless of how IP addresses are structured; role-based addressing does not directly improve NAC efficiency.

IP telephony efficiency comes primarily from QoS marking, dedicated VLANs, and call admission control - not from role-based IP address assignment.

When IP addresses are allocated based on device role or function (servers, clients, VoIP, management), security policies can be expressed as single ACL entries matching entire subnets rather than individual hosts or disparate ranges, resulting in smaller, easier-to-maintain ACLs that are applied consistently across the network.