Network Segmentation and VLAN

by Amrita Mitra | Mar 9, 2017 | CCNA, CCNP, CompTIA, Data Breaches and Prevention, Exclusive Articles, Information Security, Malware Prevention, Network Security, Security Fundamentals

Network Segmentation with Switches

Switches, like bridges, can enable two or more networks to be interconnected together. But, switching is performed in hardware, instead of software, which makes the communication between the interconnected networks much faster.

A switch learns about the Ethernet addresses of devices in each network and creates a table based on that. It examines the source and destination hardware addresses of each fragment passing through it and forwards them to the appropriate sub-network, consulting the table.

Basic switches function in layer 2 of the OSI reference model. But, there can be layer 3, layer 4 or layer 7 switches also.

Advantages of network segmentation using switches

Switching technology enables a network to be separated into different collision domains, significantly improving network performance. Switches can connect different network types, such as Ethernet and Fast Ethernet.

Moreover, switches can be used to create VLANs, which can greatly increase a network’s security.

What is VLAN?

As discussed earlier, switches can segment a network into different interconnected smaller networks. A basic switch works in layer 2 of the OSI reference model. If we look closely, here is how it works:

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