Chapter 29 Layer 2 Protocol Tunneling

2 for PAgP (Port Aggregation Protocol), LACP or UDLD (UniDirectional Link Detection).

Figure 138 L2PT Network Example

 

 

 

 

 

 

 

 

 

 

 

 

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STP

 

 

 

 

 

STP

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

STP

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

D

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1

Service Provider's

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Network

 

 

 

 

C

29.1.1 Layer-2 Protocol Tunneling Mode

Each port can have two layer-2 protocol tunneling modes, Access and Tunnel.

•The Access port is an ingress port on the service provider's edge device (1 or 2 in Figure 138 on page 292) and connected to a customer switch (A or B). Incoming layer-2 protocol packets received on an access port are encapsulated and forwarded to the tunnel ports.

•The Tunnel port is an egress port at the edge of the service provider's network and connected to another service provider’s switch. Incoming encapsulated layer-2 protocol packets received on a tunnel port are decapsulated and sent to an access port.

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XGS-4526/4528F/4728F User’s Guide