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I am trying to make sure Vlan tagging is correctly configured on our Cisco Switches. I've been seeing considerable network slow down and suspect its due to our camera traffic entering the data Vlan. We separate traffic, Vlan 1 = data, Vlan 3 = Camera.

My question is this, What is the difference between Port to Vlan and Vlan to Port?

Its confusing the hell out of me because some of our switches are cisco and others are Avaya. The two utilize different terminologies for the same technologies.

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  • I think the key here is the PVID - that's the default VLAN that traffic gets assigned to on ingress. So for the ports that the cameras plug into, the PVID needs to be 3.
    – Jim G.
    Feb 17, 2015 at 19:42
  • the cameras don't know anything about vlans so I understand that the switch has to tag the traffic but in the cisco web interface there are two options to configure. One is port to vlan and the other is vlan to port. I don't understand why there are two. They seem to be the same
    – Nate S.
    Feb 17, 2015 at 19:46
  • Usually you do not gain performance when separating traffic to different VLANs because switch still has to process all the traffic regardless of what VLAN it belongs to. I mean switch has a CPU and this CPU is being used for all the processing that happens in the switch. By creating VLANs you do not make the CPU more efficient or powerful.
    – VL-80
    Feb 17, 2015 at 19:49
  • Could you post screen shots of how your Port to Vlan and Vlan to Port pages look like?
    – VL-80
    Feb 17, 2015 at 19:50
  • You defiantly gain network performance through Vlans. That's the point. You are right about not getting better performance out of the switch though. Vlans reduce collision domain like a router would and you can QOS to give certain traffic priorities which helps increase performance as well
    – Nate S.
    Feb 17, 2015 at 20:45

2 Answers 2

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From the Cisco switch manual that I have (Cisco SG-300):

The Port VLAN Membership page displays all ports on the device along with a list of VLANs to which each port belongs.

As it says - this page displays all the ports and lists what VLANs they are members of. On this page you can see overall picture of VLAN assignment.


Use the Port to VLAN page to display and configure the ports within a specific VLAN.

Here you choose a VLAN that you want to configure and it will let you to specify settings for every port in regards to the particular VLAN that you wish to configure. For example if you are configuring VLAN 5 than this page will display settings for all ports in regards to VLAN 5 only.


You can use both ways to properly configure ports in regards to what VLANs they participate to.

As you say in your comment

One is port to vlan and the other is vlan to port. I don't understand why there are two. They seem to be the same.

They allow you to achieve same results in slightly different way.

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Under "Port to VLAN" there is an option to set the PVID. Change this to reflect the correct VLAN and you should be good.

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