Information Technology Reference
In-Depth Information
Ta b l e 5 -7
WLC Interface Types
WLC Interface Type
Description
Dynamic interface
Dedicated to WLAN client data; analogous to VLANs
Virtual interface
For L ayer 3 authentic ation and mobilit y management
AP Controller Equipment Scaling
Cisco provides different solutions to support the differing numbers of APs present in en-
terprise customers. Standalone devices, modules for Integrated Services Routers (ISR), and
modules for 6500 switches support numerous APs. Table 5-8 lists the platforms and the
number of APs supported.
Ta b l e 5 - 8
WLAN Controller Platforms
Platform
Number of Supported Access Points
Cisco 2100 series WLC
25
Cisco WLC for ISRs
25
Catalyst 3750 Integrated WLC
50
Cisco 4400 series WLC
100
Cisco 6500/7600 series WLC module
300
Cisco 5500 series WLC
500
There are two ways to scale beyond the default 48 APs on a Cisco WLC:
Use multiple AP interfaces:
This option is only supported on 4400 series controllers.
■
Use link aggregation (LAG):
This option is supported by 5500 and 4400 series con-
trollers and is the default for 3750G Integrated WLC and Catalyst 6500 series WiSM.
■
As shown in Figure 5-8, with multiple AP manager interfaces each manager interface is
mapped to a physical port. The AP load is distributed dynamically. One advantage with AP
manager interfaces is that the WLC can be connected to more than one neighbor device.
Figure 5-9 shows the use of LAG. With LAG, the system dynamically manages port re-
dundancy and load balances APs across an EtherChannel interface transparently. The limit
of 48 APs per port does not apply when LAG is enabled. With LAG enabled, the 4402
controller supports up to 50 APs, and the 4404 supports up to 100 APs. LAG is the rec-
ommended solution.
One limitation of LAG is that the WLC platforms only support one LAG group per con-
troller. When LAG is enabled, all the physical ports, excluding the services port, are in-
cluded in the bundle. Therefore, the WLC using LAG cannot be connected to more than
one neighbor device.
