Vswitch Port Data Type sorting

There are three types of Ethernet ports: Access, Hybrid, and Trunk. an Access port can belong to only one VLAN and is generally used to connect to a computer. A Trunk port can belong to multiple VLANs and receive and send packets from multiple VLANs, it is generally used for ports connected between vswitches. A Hybrid port can belong to multiple VLANs and can receive and send packets from multiple VLANs. It can be used for connections between vswitches, it can also be used to connect to a user's computer.

The Hybrid port differs from the Trunk port because the Hybrid port allows packets of multiple VLANs to be sent without tags, while the Trunk port only allows packets of the default VLAN to be sent without tags.

Note that:

1. On an Ethernet switch, the Trunk port and Hybrid port cannot be set at the same time.

2. If a port is specified as an image port, it cannot be set as a Trunk port, and vice versa. By default, the port is the Access port.

When receiving data on the port: If the port is in tagged mode, when the packet itself does not contain VLAN, the default vlan is added to the input packet. If the packet itself already contains VLAN, then, no more instances are added.

In the untagged mode, the default vlan must be added to all input packets, regardless of whether the input packets have VLAN tags.

When the port sends data: If the port is in tagged mode, if the default VLAN of the port is equal to the vlan contained in the sent data packet, the VLAN tag is removed from the sent data packet. If not, packets are sent out with VLANs To implement transparent transmission of VLANs.

In the untagged mode, the vlan id is removed from the packet regardless of the default VLAN of the port and whether it is equal to the VLAN of the data packet to be output.

Generally, tagged uses cascade between vlan switches, while untagged is used to connect PCs.

When we add a port to a created VLAN, we can specify whether to add a label to the port. If we add a label to the port, we call it a Tagged port, on the contrary, if we do not add a label to the port, we call it the Untagged port. Tagged ports are generally relay ports, that is, the connection ports between switches. The Untagged port is generally the port connecting the vswitch to the terminal.

On BigHammer6800 series switches, a port can belong to multiple VLANs in the Tagged mode, but a port can only belong to one VLAN in the Untagged mode.