CAPWAP

CAPWAP:

The functional design of the Cisco Unified Wireless Network solution, the Cisco Centralized WLAN Architecture, uses CAPWAP as its foundational protocol. It controls APs and WLANs, wraps and transmits WLAN client communications between APs and WLAN controllers, and manages and configures APs and WLANs (WLCs). The cornerstone of CAPWAP is the Lightweight Access Point Protocol (LWAPP), but Datagram Transport Layer Protection improves security (DTLS). CAPWAP, which makes use of the User Datagram Protocol (UDP), is compatible with both Internet Protocol Version 4 (IPv4) and Internet Protocol Version 6 (IPv6). The data transferred between the LAP and WLC is compressed using new IP packets by CAPWAP. Traffic that has been tunneled is subsequently switched or routed using the campus network....

Wireless Controller Port:

The physical connection to the switched network infrastructure exists through the wireless controller port. The device’s physical ports include controller ports.  The main physical controller ports are as follows:...

LAG:

Ports are aggregated by the controller through a Link Aggregation Group (LAG). The 802.3ad port aggregation standard is only partially implemented. All ports of the controller’s distribution system are combined into a single 802.3ad port channel, reducing the number of IP addresses required to configure the controller’s ports. LAG provides link redundancy between the two devices, doubling bandwidth and expanding port flexibility. A logical channel can be created by combining a number of physical ports under the control of the Link Aggregation Control Protocol (LACP), part of the IEEE specification (802.3az) (LAG). WLC Interface: Cisco Wireless Controller’s internal logic interface provides the necessary connectivity. These interfaces must be configured with an IP address, subnet mask, default gateway, and dynamic host....

WLC Interface:

The Cisco Wireless Controller provides the necessary connectivity through an internal logical interface. These interfaces must be configured with an IP address, subnet mask, default gateway, and Dynamic Host Configuration Protocol (DHCP) server. Each interface is then assigned a physical port and VLAN ID....

WLC PORTS (Logical Interfaces):

Understanding the function of each logical interface is essential to successfully installing and operating a Cisco WLC-based wireless network. The WLC’s logical interfaces are used for various tasks such as managing controllers, access points, user data, and managing wireless SSIDs broadcast by access points....

Distribution Port – Link Aggregation:

The 802.3ad port standard allows you to combine many distribution ports of all WLCs into one port. An administrator can do this to create a single comprehensive connection between the local switch and the WLC. For example, the WLC2504 has 4 Gigabit Ethernet ports and can be combined with adjacent switches to create a 4 Gigabit Ethernet connection with your wired network. To enable link aggregation, an EtherChannel must be set up on the local switch. WLC does not support Link Aggregation Control Protocol (LACP) or Cisco’s own Port Aggregation Protocol (PAgP), so it is important to set the switch to his LAG. Only one LAG group is supported per controller....

Conclusion:

The Cisco Wireless LAN Controller Interface was introduced in this article. We explored the functionality of all interfaces and ports on the WLC, including Ethernet distribution ports, service ports, redundancy ports, management interfaces, AP-manager interfaces, virtual interfaces, and dynamic interfaces....