Hubs create several problems. Collisions limit throughput as more devices are added. All traffic is visible to all devices, creating security risks. Half duplex is required, halving effective bandwidth. There's no QoS or prioritization. One malfunctioning device can disrupt everyone. These problems made hubs obsolete. You won't install new hubs, but you might encounter old ones.
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$ curl repovive.com/roadmaps/network-design/physical-and-data-link-fundamentals/hub-problems
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