Delta DVS Series User Manual

DVS Series Managed Industrial Ethernet Switches User’s Manual
3.3.1.4 CST Port Status
The type of port role of the interface:
 Root Port: It’s a concept of STP. Every non-root switch has one root port. The lowest cost of the
path to the root switch will be the root port.
 Master Port: It’s a concept of MSTP. It must meet two conditions: one is root port in CIST; the
other one is an edge port. The edge port is the port which connects two regions.
 Designated Port: The port responsible for forwarding data to the downstream network segment
or device.
 Alternate Port: The standby port for the root port or master port. If a root port or master port is
blocked, the alternate port becomes the new root port or master port.
 Backup Port: The backup port of designated ports. When a designated port is blocked, the
backup port becomes a new designated port and starts to forward data without delay. When a
loop occurs while two ports of the same MSTP device are interconnected, the device will block
either of the two ports, and the backup port is that port to be blocked.
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Delta DVS Series Specifications

General

Brand	Delta
Model	DVS Series
Category	Switch
Language	English