If available pathways do not allow all cables to be routed to the central network point, which topology is recommended?

• A. Ring topology
• B. Two-level hierarchical star
• C. Bus topology
• D. Mesh topology

Answer: (B)

When you can’t route all cables to a single central network point, use a two-level hierarchical star layout. In this approach, you place local aggregation points or distribution devices in each area and connect edge devices to those local points. Then, the local aggregators connect back to the central backbone. This arrangement keeps most cabling within manageable, area-specific runs and only requires a backbone connection from each area to the core, which fits the constraint of limited pathways.

The benefit is clear: it provides scalability and easier fault isolation. If a problem occurs in one area, it’s contained within that local star, and you don’t have to pull cables from every edge device all the way to the central point. It also simplifies expansion—new devices or entire areas can be added by connecting them to their local distribution point without reworking the entire central wiring.

Other topologies don’t fit as well in this scenario. A ring creates a continuous loop that can disrupt service if a link fails and isn’t optimal for centralized management across multiple areas. A bus relies on a single shared cable path, which becomes a bottleneck and isn’t practical with limited pathways. A full mesh offers many redundant paths but is typically unnecessary and cost-prohibitive for a building with restricted routing options, where a hierarchical star provides the right balance of manageability, performance, and scalability.