As the growing demand for Wi-Fi access, more and more wireless access points (APs) are deployed in the network to ensure the signal coverage in the enterprise buildings or campuses, which makes the network O&M harder for administrators. Wireless access controllers (ACs) come into being to settle this bottleneck by controlling and managing these multiple APs. The wireless access point has lost the individual intelligence, while the wireless access controller becomes the new "brain" for the entire WLAN.
A wireless LAN controller, or WLAN controller, monitors and manages wireless access points in bulk and allows wireless devices to connect to WLAN, a wireless network architecture. As a centralized device in the network, the wireless LAN controller is usually located at the data center, to which all the wireless APs on the network are directly or indirectly connected.
The wireless access controller takes the bandwidth produced coming from a router and stretches it to fit the network needs. Similar to an amplifier in a stereo system, the wireless controller allows devices from farther distances to connect. Besides, it enables the network administrators to check all the data related to the network and is able to detect rogue access points and recent traps generated by the access points.
When deploying enterprise WLANs, every single wireless access point was originally configured and managed independently from other APs on the same network. That's to say, each AP needs to operate individually, which is difficult to realize centralized management. What's worse, these APs can't communicate with each other, causing technical problems and resulting in unstable network conditions eventually. Unlike the traditional "without AC'' solution, adopting wireless LAN controllers when networking will solve the above-mentioned problematic issues once for all. Accompanied by fit mode APs, wireless LAN controllers can help to realize efficient and simplified network management.
Secured Wired and Wireless Network: Controlling wireless users' access privileges using a variety of deterministic criteria (authentication method, device type, application requested, etc.) to provide differentiated access to maintain security. Instead of stopping the encryption at the AP, it helps to keep WLAN traffic fully isolated until it has passed through a firewall at the wireless access controller. Detecting and stopping unauthorized (rogue) APs to prevent all unauthorized wireless connectivity in the network. WLAN controllers, literally, "lock the air."
Centralized and Flexible Network Management: Centralized wireless controller provides flexibility for deployment, which will reduce overall budget, planning tools, and time spent organizing a wireless network in the business. Enabling the centralized monitoring of the entire wireless infrastructure, which will decrease the total cost of ownership and unification of wired and wireless access, a future-proofing investment for upgrades.
Simplified Network Maintenance: Wireless LAN controllers eliminate site-surveys by including intelligent RF planning software. The self-configuring and self-healing wireless network is better for management and troubleshooting. It can accurately locate and identify each user. Due to the RF nature, the wireless access controller can easily detect interference between nearby APs and re-configure their power and channel settings automatically. If an AP goes down, it can instruct nearby APs to increase their power levels to fill the coverage gap.
It's not a simple yes-or-no question. Totally depending on your particular situation and actual needs. If your business is a small or medium-sized one, or if you haven't hired a skilled IT manager, or if you are just on a budget, sticking with "without wireless AC solution" is advisable. If you have more than four or five APs, or you just organize a relatively complex network, investing in a wireless LAN controller is totally worth the cost, just from the perspective of management and maintenance, saving both time and effort.
Before purchasing the controller, it's crucial to make sure that the type of your deployment and whether it matches the size of your organization. Normally speaking, the choice of the ac controller will depend on the number of devices that attach to a wireless network. Some wireless access controllers are built to handle the traffic of a large organization. Similarly, some wireless ACs are just designed for a small business handling day-to-day activities. WLAN controllers come in a range of sizes, formats, and licensing options, your choice is depending on whether you're deploying your WLAN at a small, midsized, or large site.
Configure the switch port, to which the WLAN controller is connected, as an IEEE 802.1Q trunk port. Note: only the necessary VLANs are allowed on the switch. Typically, the management and the AP-Manager interface of the WLAN controller are left untagged, indicating they assume the native VLAN of the connected switch, not necessary, by the way. You can assign a separate VLAN to these interfaces.