Understanding Three-Tier Network Topologies

AB

Three-tier network topology is a hierarchical design model that divides a network into three distinct layers: access layer, distribution layer, and core layer. This design model is commonly used in enterprise networks as it provides scalability, flexibility, and modularization.

The correct answers are A and B.

A. The distribution layer runs Layer 2 and Layer 3 technologies: The distribution layer is responsible for connecting the access layer to the core layer. This layer typically runs Layer 3 protocols like OSPF, EIGRP, or BGP to provide routing between VLANs or subnets. It also provides services such as filtering, policy enforcement, and Quality of Service (QoS). Additionally, it can run Layer 2 technologies like Spanning Tree Protocol (STP) to ensure loop-free connectivity.

B. The network core is designed to maintain continuous connectivity when devices fail: The core layer is the backbone of the network and is responsible for transporting large amounts of data at high speeds. It provides redundancy, load balancing, and failover capabilities to ensure that the network remains operational even when a device fails. The core layer typically uses high-speed technologies such as fiber-optic cables, and it is designed to be fault-tolerant and highly available.

C. The access layer manages routing between devices in different domains: This statement is incorrect. The access layer is responsible for connecting end-user devices like computers, printers, and IP phones to the network. It provides services such as port security, VLAN assignment, and authentication. However, it does not manage routing between devices in different domains.

D. The core layer maintains wired connections for each host: This statement is incorrect. The core layer does not maintain wired connections for each host. Instead, it provides high-speed connectivity between different parts of the network and ensures that data is transported efficiently.

E. The core and distribution layers perform the same functions: This statement is incorrect. The core and distribution layers perform different functions in the network. The core layer provides high-speed connectivity and redundancy, while the distribution layer provides services such as filtering, policy enforcement, and routing.