CTC Union VDTU2-R240W, Руководство пользователя

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switch port.
Egress and Ingress Rules:
Egress rules determine which frames can be transmitted out of a port, based on the Egress List of the VLAN associated
with it. Each VLAN has an Egress List that specifies the ports out of which frames can be forwarded, and specifies
whether the frames will be transmitted as tagged or untagged frames.
Ingress rules are a means of filtering out undesired traffic on a port. When Ingress Filtering is enabled, a port
determines if a frame can be processed based on whether the port is on the Egress List of the VLAN associated with
the frame.
When an untagged packet arrives at the switch port, the switch will write a VLAN ID into the header of the frame
according to the PVID (port VLAN) port definition. Typically, most switches today have all ports are set to a default
PVID of 1. When a tagged frame arrives at a switch port the tag is respected.
A VID defines the member of a port group. A packet can only travel inside a member port when the member port is
part of a VID port group. Different VID groups aren’t visible to one another
VID: (Virtual LAN ID) It is an definite number of ID which number is from 1 to 4094.
PVID: (Port VID) It is an untagged member from 1 to 4094 of default VLAN.
TCI (Tag Control Information field) including user priority, Canonical format indicator (CFI) and VLAN ID.
TPID (Tag Protocol Identifier) defined value of 8100 in hex. When a frame has the EtherType equal to 8100H, this frame
carries the tag IEEE 802.1Q / 802.1P.
Priority field defines user priority, giving eight (23 = 8) priority levels. IEEE 802.1P defines the operation for these 3
user priority bits. (Refer to following table)
CFI (Canonical Format Indicator) is always set to zero for Ethernet switches. CFI is used for compatibility reason
between Ethernet type network and Token Ring type network. If a frame received at an Ethernet port has a CFI set to 1,
then that frame should not be forwarded as it is to an untagged port.
VID (VLAN ID) is the identification of the VLAN, which is basically used by the standard 802.1Q. It has 12 bits and allow