Aruba Networks Version 3.3 ユーザーズマニュアル

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| Mobility Controller and Access Point Deployment
Campus Wireless Networks Validated Reference Design Version 3.3
| Design Guide
least two connections setting up redundant links to two data center distribution switches. With the 
Active-Standby configuration recommended in this VRD, this yields a full mesh between the two 
controllers and the distribution switches. The MMC-3600 does not have redundant power supplies; 
connect each appliance to discrete power sources in the data center.
Local Controller Placement
The Local Controller should be connected to the distribution layer switches in an MDF or similar 
suitable location with backup power, with each Active-Active pair connecting to separate switches. 
Using the MMC-6000 Multiservice Mobility Controller as recommended by this VRD, each blade should 
be connected to its own distribution layer switch with two 10 Gigabit Ethernet connections bonded 
with Etherchannel. A fully populated MMC-6000 chassis with four blades require eight Gigabit 
connections. Each MMC-6000 chassis should contain redundant power supplies connected to discrete 
power sources. 
AP Placement, Power, and Connectivity
Mobility Controller and Thin AP Communication
Mobility Controllers and thin APs work as a system. Configuration for all APs is automated and 
centralized on the Mobility Controller. Upon bootup, each AP uses DHCP to obtain its IP information 
then connects to the Local Controller to retrieve its initial configuration, and to check for firmware 
updates. Subsequent configuration changes are performed centrally within the Local Controller and 
pushed to each AP. If the firmware on the AP does not match the controller, the AP will automatically 
use either FTP or TFTP to upgrade itself to the new firmware stored on the Local Controller with no 
administrator intervention.
Communication between the AP and the Local Controller at the Aggregation layer occurs using a GRE 
tunnel established during the boot process. Because the GRE tunnel is in place, all wireless traffic is 
transmitted directly to the controller, so no special VLANs need to be deployed for APs; they will 
function over the existing infrastructure as would any other client. This avoids the “VLAN explosion” 
problem in some other architectures where every user VLAN must terminate on every AP throughout 
the enterprise. On the other side of the GRE tunnel, the user traffic is then switched to the correct 
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Web
File
RADIUS
PBX
Distribution
switches
Master
Mobility
Controller
Data center
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Local
Mobility
Controller
Distribution layer
switch
Two 10 gigabit links
Distribution