Port-based VLAN
Port-based VLANs group VLAN members by port. A port forwards traffic for a VLAN only after it is assigned to the VLAN.
Port link type
You can configure the link type of a port as access, trunk, or hybrid. The link types use the following VLAN tag handling methods:
•Access port—An access port belongs to only one VLAN and sends traffic untagged. It is usually used to connect a terminal device unable to identify VLAN tagged-packets or when it is unnecessary to separate different VLAN members. As shown in Figure 133, Device A is connected to common PCs that cannot recognize VLAN tagged-packets, and you must configure Device A's ports that connect to the PCs as access ports.
•Trunk port—A trunk port can carry multiple VLANs to receive and send traffic for them. Except traffic from the port VLAN ID (PVID), traffic sent through a trunk port will be VLAN tagged. Usually, ports that connect network devices are configured as trunk ports. As shown in Figure 133, Device A and Device B need to transmit packets of VLAN 2 and VLAN 3, and you must configure the ports interconnecting Device A and Device B as trunk ports and assign them to VLAN 2 and VLAN 3.
•Hybrid port—A hybrid port allows traffic of some VLANs to pass through untagged and traffic of some other VLANs to pass through tagged. Usually, hybrid ports are configured to connect devices whose support for VLAN-tagged packets are uncertain. As shown in Figure 133, Device C connects to a small-sized LAN in which some PCs belong to VLAN 2 and other PCs belong to VLAN 3, and Device B is uncertain about whether Device C supports VLAN-tagged packets. Configure on Device B the port connecting to Device C as a hybrid port to allow packets of VLAN 2 and VLAN 3 to pass through untagged.
Figure 133 Port link types
VLAN 2
VLAN 2
VLAN 3 | Device A | Device B | Device C |
Access links are required
Trunk links are reuqired
VLAN 3
Hybrid links are required
135
