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New Member

Can viruses cut across VLANs?

I have one VLAN with email-enabled workstations and one VLAN with non-email workstation running on the same physical network. The VLANs can't see each other. So can a virus still cross over VLANs? Thanks in advance


Re: Can viruses cut across VLANs?


a virus can spread itself to other computers using a network communication, such as a tcp session between two computers, in your case the VLANs can t see each other it s okay but it still can communicate with each other using a layer 3 device if configured to do so.

so if two computers from two differents vlan in your network communicate with each other using a L3 device so there is a communication and the virus can cross from one computer in vlan x to another computer in vlan y, if the virus is designed to do so.


do rate if it does help

New Member

Re: Can viruses cut across VLANs?

It is possible, but highly unlikely, that a virus could interfere with the switch to "break" the VLAN setup. If the virus causes a CAM table overflow the switch may revert to acting as a hub, and allow traffic to transverse the VLANs. In order to prevent this, limit teh number of MAC addresses that the switch will store on host ports.