Hubs

Correct Answer: Replace the hub with a switch.

The best way to improve the performance of a network that is experiencing high latency and decreased throughput due to utilising a hub is to replace the hub with a switch. A switch, unlike a hub, has the capability to direct network traffic specifically to the devices for which the traffic is intended. This specificity significantly reduces network traffic, which in turn decreases latency and enhances throughput. Adding more hubs would only exacerbate the problem, as hubs indiscriminately broadcast all network traffic to all devices. Thus, answer 'Add more hubs' is incorrect. Disabling unused ports on the hub would not improve network performance because the hub would still broadcast all network traffic to all active ports. Consequently, answer 'Disable unused ports on the hub' is incorrect. Finally, restarting the hub would not remedy the inherently inefficient nature of a hub's operation, which is the underlying cause of the high latency and decreased throughput, thus answer 'Restart the hub' is also incorrect.

Correct Answer: Check each connection and port on the hub.

The best course of action would be to 'Check each connection and port on the hub.' This should be the first step as it can help to identify if there are any physical problems such as loose or damaged connections causing the issue. The option 'Replace the hub immediately' may not be necessary as the problem could be as simple as restarting or adjusting the hub. 'Swap the working workstations with the ones reporting issues' could potentially help to determine the issue, but this would require more work and time than simply checking the connections. Adding more hubs, according to the option 'Add more hubs to the network' will not solve the current issues but might further complicate the network.

Correct Answer: Increased chance of collisions.

When a network administrator installs an 8-port hub in a small office and plans to connect more devices in the future, the issue that may arise is an 'Increased chance of collisions.' Hubs do not manage traffic; they just repeat all incoming traffic to all ports. Thus, as more devices are added, there is a greater chance of collisions, or multiple devices transmitting data at the same time, leading to loss of data. The other answers are incorrect. 'Increased network security' is incorrect as adding more devices usually results in more potential points of failure or attack, thus reducing security. 'Decreased broadcast radius' is incorrect as the broadcast radius is not dependent on the number of devices but on the network structure and the type of device used. Finally, 'Poor VLAN performance' is also incorrect as VLANs are not typically used with hubs, they are more commonly used with switches.