CANOGA PERKINS 9160 10 Gigabit Ethernet Network Interface Device - Manual (Page 28)

Managing the Network Interface
The Switch Configuration menu offers options to set network parameters; see Table 5.
Table 5. Network Spanning Tree Parameters Options
Menu Item Description
1. Global Spanning Tree Parameters Set the network-wide parameters
2. Multiple Spanning Tree Parameters Set and view Multiple Spanning Tree instances
3. Global Spanning Tree Report View current network-wide parameters
4. Lag Configuration View the current information for the network and port
5. VLAN Configuration Set the VLAN parameters
6. Double Tagging Configuration Enable or disable double tagging and set the PVID per port
Ethernet bridges or switches use the Spanning Tree Protocol (STP), an algorithm that creates a logical
topology that connects all network segments and ensures only one path between any two stations.
When STP is enabled, the 9160 monitors the incoming data packets and periodically sends Bridge
Protocol Data Units (BPDU). STP monitors the incoming BPDUs to detect any loops. If the same
BPDU arrives on two ports, STP blocks one port to remove the loop. Because this tree-like structure
spans all nodes in the network, it is called Spanning Tree. Figure 4 shows a typical STP application.
Note: For details on the Spanning Tree Algorithm, see the IEEE 802.1 specifications.
A
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A small test network
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Spanning Tree from source (C)
Figure 4. Typical Spanning Tree Application.
In a service provider environment, you can set up a single LAG that includes VLANS from different
customers. The tagging and double tagging features, when enabled, keep the ID tag on a packet as it
exits a port; or when disabled, strip the ID tag as it exits a port. The customer's tag for a VLAN is
assigned through the VLAN; the service provider's (double) tag is derived from the PVID and
assigned before the packet exits the 9160. Follow these guidelines:
• Enable double tagging on the service provider port and disable it on the customer port.
• Be sure to include the port for each VLAN in the LAG.
• The service provider tag priority is derived from the port priority.
• If you set up Pbit translation, the translation occurs before the Pbit is copied to the service
provider tag.
9160 10 Gigabit Ethernet Network Interface Device 3-16