Cisco 3750G - Catalyst Integrated Wireless LAN Controller Configuration Manual page 419

Chapter 17 Configuring IEEE 802.1Q and Layer 2 Protocol Tunneling
Figure 17-4
Figure 17-5
In an SP network, you can use Layer 2 protocol tunneling to enhance the creation of EtherChannels by
emulating a point-to-point network topology. When you enable protocol tunneling (PAgP or LACP) on
the SP switch, remote customer switches receive the PDUs and can negotiate the automatic creation of
EtherChannels.
OL-8550-02
Layer 2 Protocol Tunneling
Customer X Site 1
VLANs 1 to 100
VLAN 30
VLAN 30
Switch A
Switch B
VLAN 40
Customer Y Site 1
VLANs 1 to 200
Layer 2 Network Topology without Proper Convergence
Customer X
virtual network
VLANs 1 to 100
Service
provider
Trunk
Trunk
ports
ports
Switch C
Switch D
Trunk Trunk
ports
ports
VLAN 40
Trunk
Asymmetric link
Catalyst 3750 Switch Software Configuration Guide
Understanding Layer 2 Protocol Tunneling
Customer X Site 2
VLANs 1 to 100
VLAN 30
Customer Y Site 2
VLANs 1 to 200
17-9