2.2. VLANs

For years, networks have been designed in a flat architecture. By flat I mean they have consisted of multiple hubs or bridges that reside in a single broadcast domain. If any device sent a broadcast packet, every system on the network would have to read the data, even if it was not meant for that device. At that point in history, a switch was treated as a single broadcast domain. Having a single broadcast domain limits the number of devices you can connect to the network. There are other downsides in addition to just having one huge broadcast domain. One large broadcast domain limits your ability to secure the network because any end station could connect into any switch port and have access to all of the other devices. Making separate ...

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