Cisco's hierarchical internetworking model is a (a) _ _ _ _ _ _ _ _ _ _ layer model for network design proposed by Cisco.

• A. Two
• B. Three
• C. Four
• D. Five

Answer: (B)

Cisco's hierarchical internetworking model uses three layers: Access, Distribution, and Core. This three-layer structure is designed to separate responsibilities so the network scales more easily, configurations stay organized, and changes in one area don’t ripple uncontrollably into others. The Access layer plugs end devices and user-facing ports, the Distribution layer handles routing, policy enforcement, and inter-VLAN communication, and the Core layer provides a fast, high-capacity backbone for interconnecting distribution blocks. Because of this clear separation, the design is described as a three-layer model, which is why the correct answer corresponds to the number three.