200-301 Question 45
Select 3A network engineer is designing a three-tier architecture for a corporate network. The design must ensure scalability, redundancy, and efficient communication between layers. Which of the following devices and functions are typically associated with the distribution layer in a three-tier architecture?
- A
Aggregates traffic from access layer switches and forwards it to the core layer.
- B
Provides end-user device connectivity through access switches.
- C
Implements routing between VLANs for inter-VLAN communication.
- D
Handles high-speed backbone switching to connect different distribution blocks.
- E
Applies network policies such as QoS, filtering, and security access control.
Show answer and explanation
Correct answers: A, C, E
Explanation
In the three-tier architecture, the distribution layer serves as the intermediary between the access and core layers. It aggregates traffic from access layer switches, performs inter-VLAN routing, and applies network policies such as QoS and security filtering. These functions ensure efficient communication, scalability, and policy enforcement within the network.
- A. Correct.
Correct: The distribution layer aggregates traffic from the access layer and forwards it to the core layer, acting as an intermediary between the two layers.
- B. Incorrect.
Incorrect: Providing end-user device connectivity is a function of the access layer, not the distribution layer.
- C. Correct.
Correct: The distribution layer often implements inter-VLAN routing to allow communication between different VLANs.
- D. Incorrect.
Incorrect: High-speed backbone switching is a function of the core layer, which is designed for fast data transfer between distribution blocks.
- E. Correct.
Correct: The distribution layer is responsible for applying network policies such as QoS, access control, and filtering to ensure secure and efficient traffic flow.