CompTIA N10-009 Topologies and Network Design Guide
March 29, 2026
Study CompTIA N10-009 Topologies and Network Design: key concepts, common traps, and exam decision cues.
On this page
Topology questions are traffic-and-failure-domain questions. CompTIA is usually not asking you to pick the fanciest-sounding architecture. It is testing whether you can choose a topology that fits scale, resiliency, growth pattern, and operational simplicity.
Spine-and-leaf: A data-center topology that reduces east-west bottlenecks by connecting leaf switches to a shared spine layer.
Collapsed core: A design where distribution and core functions are combined, often to simplify smaller environments.
Hub-and-spoke: A design where remote locations connect through a central site rather than directly to every other site.
What CompTIA is really testing
The strongest answers usually depend on whether you can balance:
simplicity versus resilience
branch needs versus campus needs versus data-center needs
east-west traffic versus north-south traffic
growth expectations versus current size
Match the topology to the problem
Topology or architecture
Strongest fit
star
simple access designs where central aggregation is acceptable
hub-and-spoke
branch environments centered on one main site
full mesh
high resilience between many nodes, with higher complexity and cost
three-tier
larger campus or enterprise separation of access, distribution, and core
collapsed core
smaller environments that want simpler design with some hierarchy
spine-and-leaf
data-center style east-west traffic and scalable high-speed fabric
A simple topology view
flowchart TD
A["Remote branch A"] --> H["Central site"]
B["Remote branch B"] --> H
C["Remote branch C"] --> H
D["Leaf switch 1"] --> S["Spine layer"]
E["Leaf switch 2"] --> S
What to notice:
the top half shows hub-and-spoke style centralization
the bottom half shows spine-and-leaf style data-center fabric
the right answer depends on the traffic pattern and environment, not on which diagram looks more modern
Why design labels matter
CompTIA often writes the clue into the traffic pattern:
many remote branches depending on one main site points toward hub-and-spoke thinking
lots of server-to-server traffic points more toward spine-and-leaf than a tiny branch design
a modest campus that does not need a separate core may fit collapsed core better than a full three-tier build
Common traps
treating every redundancy question like a full-mesh answer
confusing logical architecture with the exact physical cable layout
using a data-center pattern for a small branch-office problem
assuming the most resilient design is always the most appropriate design
What strong answers usually do
tie the topology choice to traffic flow and failure-domain needs
choose the simplest design that meets growth and resilience requirements
recognize when branch, campus, and data-center patterns differ
avoid overbuilding small environments with architectures meant for another scale
Decision order that usually wins
First classify the environment as branch-centralized, data-center east-west heavy, or smaller hierarchy needing simplification.
If remote sites depend on a main site, think hub-and-spoke.
If the clue is scalable east-west traffic in a data center, think spine-and-leaf.
If the environment is smaller and a full three-tier design is unnecessary, think collapsed core.
Network+ usually rewards the topology that fits the operational scale rather than the most advanced-sounding design.