ZyXEL Communications MES-3528 - Layer 2 Protocol Tunneling Mode

Chapter 28 Layer 2 Protocol Tunneling
MES-3528 User’s Guide
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2 for PAgP (Port Aggregation Protocol), LACP or UDLD (UniDirectional Link
Detection).
Figure 136 L2PT Network Example
28.1.1 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 136 on page 254) 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.
1
2
A
B
Service Provider's
Network
C
D
STP
STP
STP