Operation Manual – VLANH3C S5600 Series Ethernet Switches Chapter 1 VLAN Overview1-6Note:Before assigning an access or hybrid port to a VLAN, create the VLAN first.1.2.3 Configuring the Default VLAN ID for a PortAn access port can belong to only one VLAN. Therefore, the VLAN an access portbelongs to is also the default VLAN of the access port. A hybrid/trunk port can belong tomultiple VLANs, so you should configure a default VLAN ID for the port.After a port is added to a VLAN and configured with a default VLAN, the port receivesand sends packets in a way related to its link type. For detailed description, refer to thefollowing tables:Table 1-1 Packet processing of an access portProcessing of an incoming packetFor an untaggedpacket For a tagged packetProcessing of anoutgoing packetReceive the packet andtag the packet with thedefault VLAN tag.z If the VLAN ID is just the defaultVLAN ID, receive the packet.z If the VLAN ID is not the defaultVLAN ID, discard the packet.Strip the tag fromthe packet andsend the packet.Table 1-2 Packet processing of a trunk portProcessing of an incoming packetFor an untagged packet For a tagged packetProcessing of anoutgoing packetz If the port has alreadybeen added to its defaultVLAN, tag the packetwith the default VLANtag and then forward thepacket.z If the port has not beenadded to its defaultVLAN, discard thepacket.z If the VLAN ID is one ofthe VLAN IDs allowedto pass through theport, receive thepacket.z If the VLAN ID is notone of the VLAN IDsallowed to passthrough the port,discard the packet.z If the VLAN ID is justthe default VLAN ID,strip off the tag andsend the packet.z If the VLAN ID is notthe default VLAN ID,keep the original tagunchanged andsend the packet.
