What do you need to know about VLANs?
An access port is a member of a single VLAN and connects to a computer, printer, or other device on the edge of a network. A trunk port connects the switch to a router or to other switches; it must participate in multiple VLANs because all traffic that passes between the switch and the rest of the network must go through that port.
Why is VLAN tagging not included in NIC drivers?
For some reason some NIC vendors seem to implement VLAN tagging in their drivers but not the creation of multiple virtual interfaces. This makes the VLAN tagging feature mostly pointless (outside of a few network troubleshooting scenarios). Some servers (and some workstations, but it is less common) are set up to be able to trunk with a switch.
Can a NIC be used as a VLAN layer?
In some cases it may not even be practical. A second approach is for the OS to implement a generic VLAN layer which handles the VLAN encapsulation and presents virtual interfaces. This can be done with virtually any NIC. Linux has had support for this for ages but afaict windows only added support recently.
How did Ethernet networks work before VLANs and switches?
In the old days before switches and VLANs existed, Ethernet networks connected via hubs. Hubs placed all networked hosts onto a single ethernet segment. This was a bit like chaining each host to the next one. This was still an improvement on older token-bus networks. At least a host failure does not cause a break in the chain.
How can I block VLAN on my router?
– spanning-tree portfast <– portfast enabled, which disabled spanning-tree n the port, never want this on a trunk as it creates a LAN loop friendly environment. Try the following on both switches: On “MYSWITCH” / 2950, paste the following: On ” (main switch) 3560″, paste the following: ! 12-29-2015 07:56 AM 12-29-2015 07:56 AM Ah! Ok.
Is it possible to restrict IP traffic between VLANs?
If you need to restrict IP traffic between VLANs, you can use IP access lists or firewalls. But L2 traffic can’t cross between VLANs, at least it’s not supposed to. To get technical, an Ethernet frame with a particular source and destination address will not pass from one VLAN to another under normal circumstances.
Can a VLAN Cross over to another VLAN?
The idea behind this misconception is that traffic from one VLAN can’t cross-over to another VLAN. This bumper-sticker wisdom comes from the loose use of another term; “traffic.” L3 traffic—that is, IP traffic—does pass between VLANs with the help of a router, whether a physical router or a virtual router within a L3 switch.