Configuring Cisco Discovery Protocol - Cisco SD2008T-NA Configuration Manual

Chapter 7 Controlling Lightweight Access Points
2.

Configuring Cisco Discovery Protocol

Cisco Discovery Protocol (CDP) is a device discovery protocol that runs on all Cisco-manufactured
equipment. A device enabled with CDP sends out periodic interface updates to a multicast address in
order to make itself known to neighboring devices.
The default value for the frequency of periodic transmissions is 60 seconds, and the default advertised
time-to-live value is 180 seconds. The second and latest version of the protocol, CDPv2, introduces new
time-length-values (TLVs) and provides a reporting mechanism that allows for more rapid error tracking,
thereby reducing down time.
CDPv1 and CDPv2 are supported on the following devices:
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This support enables network management applications to discover Cisco devices.
These TLVs are supported by both the controller and the access point:
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OL-9141-03
When CCX v4 is not enabled on either the controller or the client being tested, fewer details appear:
Ping Link Test to 00:0d:88:c5:8a:d1.
Link Test Packets Sent.......................... 20
Link Test Packets Received...................... 20
Local Signal Strength........................... -49dBm
Local Signal to Noise Ratio..................... 39dB
To adjust the link-test parameters that are applicable to both the CCX link test and the ping test, enter
these commands from config mode:
config > linktest frame-size size_of_link-test_frames
config > linktest num-of-frame number_of_link-test_request_frames_per_test
2000, 2100 and 4400 series controllers
Note CDP is not supported on the controllers that are integrated into Cisco switches and routers,
including those in the Catalyst 3750G Integrated Wireless LAN Controller Switch, the Cisco
WiSM and the Cisco 28/37/38xx Series Integrated Services Router.
LWAPP-enabled access points
1000 series access points that run VxWorks
An access point connected directly to a 2000 or 2100 series controller
Device-ID TLV: 0x0001—The host name of the controller or the access point.
Address TLV: 0x0002—The IP address of the controller or the access point.
Port-ID: 0x0003—The name of the interface on which CDP packets are sent out.
Capabilities TLV: 0x0004—The capabilities of the device. The controller sends out this TLV with
a value of Host: 0x10, and the access point sends out this TLV with a value of Transparent Bridge:
0x02.
Configuring Cisco Discovery Protocol
Cisco Wireless LAN Controller Configuration Guide
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