A community college district collapses dozens of VLAN STP instances into a few MST instances to cut CPU on older access switches. What is the primary purpose of that MST mapping?
Select an answer to reveal the explanation.
Short Explanation
Imagine running a separate traffic plan for every classroom hallway—that’s dozens of PVST instances. MST bundles many VLANs onto a handful of shared plans so old switches stop grinding CPU. Same loop protection, fewer topologies to compute.
Full Explanation
MST (802.1s) maps groups of VLANs to a small number of spanning-tree instances, reducing CPU and memory versus per-VLAN PVST/Rapid-PVST at scale. Instance mapping and region configuration must be consistent; boundaries with Rapid-PVST need careful interoperability design. MST does not eliminate the need for loop prevention, nor does it inherently force one root MAC for every VLAN outside the instance model. The college’s goal—fewer topologies on older access switches—is exactly why MST instance mapping exists.