A VLAN is a group of switch ports administratively configured to share the same broadcast domain.
PRIVATE VLANs –
Private VLANs (PVLANs) are used mainly by service providers. The main purpose of Private VLAN (PVLAN) is to provide the ability to isolate hosts at Layer 2 instead of Layer 3.By using PVLAN we are splitting that domain into some smaller broadcast domains. In other words we may summarize Private Vlan as “Vlans in Vlan“.
Below tables enlists the difference between both:
VLAN vs PRIVATE VLAN
|1||Different Vlans must belong to different IP subnets.||PVLANs belong to the same IP subnet
|2||Vlan works in Layer 2 and Layer 3 ||PVLAN is method to segment device at layer 2
|3||Vlan is the basic requirement for all LAN |
|PVLANs are required for specific requirements wherein endpoints of same VLAN should not communicate to each other. E.g. – Mainly in ISP scenarios to prevent different customer from communicating to each other on same LAN segment.
|4||Intervlan communication is performed at L3 SVI level||PVLAN to outside communication is performed via Primary VLAN.