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
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.
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.
Table of ContentsIntroductionVersion HistoryPossible Future
UpdatesDocuments PurposeNAT Operation in ASA 8.3+ SectionsRule Types
Network Object NATTwice NAT / Manual NATRule Types used per SectionNAT
Types used with Twice NAT / Manual NAT and Network Obje...
Table of Contents Introduction:This document describes details on how
NAT-T works. Background: ESP encrypts all critical information,
encapsulating the entire inner TCP/UDP datagram within an ESP header.
ESP is an IP protocol in the same sense that TCP an...