What is tag based VLAN?

Tag-based VLANs are based on IEEE 802.1Q specifications. Traffic is forwarded to VLAN member ports based on identifying VLAN tags in data packets. You can also configure the switch to interoperate with existing tag-based VLAN networks and legacy non-tag networks.

Which is the 802 specification for VLANs?

IEEE 802.1Q, often referred to as Dot1q, is the networking standard that supports virtual LANs (VLANs) on an IEEE 802.3 Ethernet network. The standard defines a system of VLAN tagging for Ethernet frames and the accompanying procedures to be used by bridges and switches in handling such frames.

What is the IEEE 802.1Q VLAN tagging standard?

(August 2019) IEEE 802.1Q, often referred to as Dot1q, is the networking standard that supports virtual LANs (VLANs) on an IEEE 802.3 Ethernet network. The standard defines a system of VLAN tagging for Ethernet frames and the accompanying procedures to be used by bridges and switches in handling such frames.

Where does the VLAN tag go on an Ethernet frame?

If you are using the switch defaults for VLANs, the VLAN tag that will be placed on the frame is VLAN1. When placing a VLAN tag (also known as an IEEE 802.1Q tag) on the Ethernet frame, the four bytes of data, which make up the VLAN tag, are inserted before the Type field, as shown in the following figure.

What’s the difference between tagged and untagged VLANs?

We can select each port a one VLAN, which outgoings packets are untagged. A VLAN that complies with the 802.1Q standard, including priority settings, and allows a port to join multiple VLANs. A VLAN that does not use or forward 802.1Q VLAN tagging, including priority settings.

How does an 802.1Q Ethernet frame work?

Here’s an example of an 802.1Q Ethernet frame. As you can see it’s the same as a normal Ethernet frame but we have added a tag in the middle (that’s the blue field). In our tag you will find a “VLAN identifier” which is the VLAN to which this Ethernet frame belongs. This is how switches know to which VLAN our traffic belongs.