ZyXEL Communications XGS4700-48F - Layer-2 Protocol Tunneling Mode

Chapter 29 Layer 2 Protocol Tunneling
XGS4700-48F User’s Guide
294
2 for PAgP (Port Aggregation Protocol), LACP or UDLD (UniDirectional Link
Detection).
Figure 143 L2PT Network Example
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 143 on page 294) 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