In this exercise, you will learn about the physical infrastructure connections of WLAN components, including AP, WLC, access/trunk ports, and LAG. You will learn how the connections are made between the WLC and APs.

Learning Outcomes
This exercise covers the following:

Know about Connection of Acess Point and Wireless LAN Controller to Switch
Your Devices
This exercise contains supporting materials for Cisco.

Practice Labs screenshot.

Connection of Acess Point and Wireless LAN Controller to Switch
Access point is connected via a wired connection to a switch port. This switch port could be in access or trunk mode. In the case of an autonomous access point, the switch port would be in trunk mode, and for a lightweight access point, switch port would be in access mode.

Figure 3.1
Figure 3.1: Displaying WLC and access point connections.
The switch port that connects to the WLC is configured as a trunk port that allows traffic to be carried for all of the configured VLANs. These VLANs could be the management VLAN or Wireless clients VLAN.

Once the number of APs increase along with the wireless clients, the traffic can overwhelm the controller. As shown in the figure above, you have two connections going from the switch to WLC. These two physical links are combined to create one virtual link called the link aggregation port or LAG.

Aggregation port is, in fact, one big virtual link to the switch as it groups physical ports together to create virtual communication. This virtual link is two times faster than each individual physical port. The advantage of using LAG is that you increase the speed while still keeping the idea of one single link. If any of the physical ports in a LAG becomes faulty, you still have the connectivity via the working physical port. Hence you don’t lose communication to the switch, so there is a redundancy aspect on top of an efficiency aspect when LAG is used.

If you are connecting a wireless LAN controller into a network and you want to do link aggregation, then you have to configure it as IEEE 802.3ad link aggregation.

They are the basic components required to connect APs and WLC to the switch.