Question 57

Explanation

The correct answer: The star topology is the most common physical topology for local area networks (LANs). In a star topology, all nodes (computers, printers, etc.) are connected to a central device, such as a hub or a switch. This central device manages and controls all functions of the network. If one node fails, it doesn’t affect the rest of the network. Furthermore, adding, removing, or changing nodes is easy and can be done without disrupting the network. However, the main disadvantage is that if the central device fails, the entire network goes down. The incorrect answers: In a bus topology, all devices are connected to a central cable, called the bus or backbone. This topology was common in the early days of Ethernet LANs, but it has largely been replaced by the star topology due to its limitations, such as difficulty in troubleshooting, limited cable length and number of devices, and the entire network shuts down if there is a break in the main cable. In a mesh topology, every device is connected to every other device on the network through a dedicated point-to-point link. This provides high redundancy, but it is very expensive and complex to implement and manage, making it less suitable for a LAN. In a ring topology, each device is connected to two other devices, forming a circular or ring-like structure. Data travels around the ring in one direction. While it's simple to set up and expand, it's not commonly used in LANs because if one node fails, it can bring down the entire network.