Same VLAN or Not? — TechKnowSurge

About this interactive

Physical segmentation gives every network its own switches. That works, but every extra switch is another cost and another device to manage. VLANs, virtual local area networks, segment the network logically instead. A switch's ports are assigned to VLANs: here ports 1 to 8 are VLAN 10, 9 to 16 VLAN 20 and 17 to 24 VLAN 30. Devices on ports in the same VLAN can reach each other at layer 2 and hear each other's broadcasts. Devices on different VLANs cannot, even on the same switch, unless a router or other layer 3 device joins the VLANs. The logical layout does not have to follow the physical one. When the switches in buildings A, B and C carry the VLANs between them, a Sales PC in building A and a Sales PC in building C are on one network, while two PCs on neighbouring ports of one switch can be on two. So read the VLAN, not the building or the switch.

What you'll learn

Decide whether two devices share a layer 2 network from the VLANs their switch ports are assigned to, not from the switch or building they are plugged into
Explain logical segmentation: VLANs split one switch into separate broadcast domains, and one VLAN can span switches in different buildings, so the logical layout differs from the physical one

Aligned to

CompTIA Security+

3.1 Compare and contrast security implications of different architecture models.

3.2 Given a scenario, apply security principles to secure enterprise infrastructure.

2.5 Explain the purpose of mitigation techniques used to secure the enterprise.

Key terms

Virtual LAN: A logical grouping of network devices that behave as if they are on the same network regardless of physical location.
Broadcast Domain: A network segment in which a broadcast sent by one device is received by all other devices within that segment; routers define the boundaries of broadcast domains by not forwarding broadcast traffic.
VLAN ID: A numerical identifier assigned to a VLAN that distinguishes it from other VLANs on the network.
Network Segmentation: The practice of dividing a network into smaller segments to improve performance and limit the spread of security threats.
Local Area Network: A network that connects devices within a limited geographic area such as a home, office floor, or building, where all devices share the same broadcast domain and communicate at high speeds with low latency. A router defines the boundary of a LAN by separating it from other networks.

Topics

Virtual Lan Logical Segmentation Broadcast Domain Network Segmentation Interactive Streak Sort

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