Cisco Cisco Aironet 702W Access Point Guida All'Installazione
10
Note
Make sure that the controller is set to the current time. If the controller is set to a time that has already occurred, the
access point might not join the controller because its certificate may not be valid for that time.
access point might not join the controller because its certificate may not be valid for that time.
Access points must discovered a controller before they can become an active part of the network. The access point supports
these controller discovery processes:
these controller discovery processes:
•
Layer 3 CAPWAP discovery—The access point performs a local broadcast (255.255.255.255) discovery request to find any
contollers on the same subnet/vlan. The request can be forwarded to other networks by the IP helper featuer that is present
on switches and router.
contollers on the same subnet/vlan. The request can be forwarded to other networks by the IP helper featuer that is present
on switches and router.
•
Locally stored controller IP address discovery—If the access point was previously joined to a controller, the IP addresses of
the primary, secondary, and tertiary controllers are stored in the access point’s non-volatile memory. This process of storing
controller IP addresses on an access point for later deployment is called priming the access point. For more information
about priming, see the
the primary, secondary, and tertiary controllers are stored in the access point’s non-volatile memory. This process of storing
controller IP addresses on an access point for later deployment is called priming the access point. For more information
about priming, see the
•
DHCP server discovery—This feature uses DHCP option 43 to provide controller IP addresses to the access points. Cisco
switches support a DHCP server option that is typically used for this capability. For more information about DHCP option
43, see the
switches support a DHCP server option that is typically used for this capability. For more information about DHCP option
43, see the
.
•
DNS discovery—The access point can discover controllers through your domain name server (DNS). For the access point
to do so, you must configure your DNS to return controller IP addresses in response to
CISCO-CAPWAP-CONTROLLER.localdomain, where localdomain is the access point domain name. Configuring the
CISCO-CAPWAP-CONTROLLER provides backwards compatibility in an existing customer deployment. When an access
point receives an IP address and DNS information from a DHCP server, it contacts the DNS to resolve
CISCO-CAPWAP-CONTROLLER.localdomain. When the DNS sends a list of controller IP addresses, the access point
sends discovery requests to the controllers.
to do so, you must configure your DNS to return controller IP addresses in response to
CISCO-CAPWAP-CONTROLLER.localdomain, where localdomain is the access point domain name. Configuring the
CISCO-CAPWAP-CONTROLLER provides backwards compatibility in an existing customer deployment. When an access
point receives an IP address and DNS information from a DHCP server, it contacts the DNS to resolve
CISCO-CAPWAP-CONTROLLER.localdomain. When the DNS sends a list of controller IP addresses, the access point
sends discovery requests to the controllers.
Preparing the Access Point
Before you mount and deploy your access point, we recommend that you perform a site survey (or use the site planning tool) to
determine the best location to install your access point.
determine the best location to install your access point.
You should have the following information about your wireless network available:
•
Access point locations
•
Access point mounting options (Wall and Junction Box mounting only)
•
Access point power options: power supplied by the recommended external power supply (with power adapter
AIR-PWR-C=), a DC power supply, PoE from a network device (802.3af/at), or a PoE power injector/hub (the
Cisco-recommended injector is the AIR-PWRINJ4=), usually located in a wiring closet.
AIR-PWR-C=), a DC power supply, PoE from a network device (802.3af/at), or a PoE power injector/hub (the
Cisco-recommended injector is the AIR-PWRINJ4=), usually located in a wiring closet.
Note
PoE-Out is available via LAN port 4
Cisco recommends that you make a site map showing access point locations so that you can record the device MAC addresses
from each location and return them to the person who is planning or managing your wireless network.
from each location and return them to the person who is planning or managing your wireless network.
Table 1
Access Point Power Sources and PoE-Out Levels
Power Input Source
Maximum PoE-Out Power
802.3af / AIR-PWRINJ5
No power available for the PoE-out port
802.3at/AIR-PWRINJ4
Class 2, 6.49W (7W with cable losses)
AIR-PWR-C
Class 0, 12.95W (15.4W with cable losses)