A police records bureau designs a compact campus where access switches uplink only to a distribution layer that also acts as the core, with no separate core tier. Which topology architecture is that?
Select an answer to reveal the explanation.
Short Explanation
Small campuses often smash the core and distribution into one layer—like combining the expressway and the interchange. Access switches still uplink up, but there's no third core tier. That's two-tier, aka collapsed core.
Full Explanation
A compact police-records campus that uplinks access switches only to a distribution layer which also acts as the core—with no separate core tier—is a two-tier collapsed-core design. In that architecture, distribution and core functions are combined so smaller sites avoid a dedicated core layer while still presenting a hierarchical access-to-distribution uplink pattern. That matches the bureau's stated topology: access uplinks only to distribution, and distribution absorbing core duties.
A full three-tier design with dedicated access, distribution, and core layers fails because the stem explicitly has no separate core tier. A spine-leaf fabric where every leaf has equal-cost uplinks to every spine fails by concept: spine-leaf is a data-center-oriented leaf-spine mesh optimized for east-west server traffic, not the described campus collapsed core. A pure hub-and-spoke WAN with remote sites dialing into a single concentrator fails because that describes wide-area site aggregation, not the LAN campus tiering inside the compact records facility.
Exam caveat: Collapsed core means two tiers (access + combined distribution/core). Three-tier means three distinct roles. Do not confuse collapsed core with spine-leaf simply because both can be "non-three-tier" in some diagrams—the connectivity pattern and design intent differ.
Operational check: Document that access switches uplink only to the collapsed distribution/core pair (or stack/VSS/vPC pair), that there is no additional core tier in the forwarding path, and that inter-VLAN and campus aggregation occur on that combined layer. If you find a separate core chassis in path, the live network is three-tier despite the intended collapsed-core design.