The switch uses the location service feature to send location and attachment tracking information for its connected devices
to a Cisco Mobility Services Engine (MSE). The tracked device can be a wireless endpoint, a wired endpoint, or a wired switch
or controller. The switch notifies the MSE of device link up and link down events through the Network Mobility Services Protocol
(NMSP) location and attachment notifications.
The MSE starts the NMSP connection to the switch, which opens a server port. When the MSE connects to the switch there are
a set of message exchanges to establish version compatibility and service exchange information followed by location information
synchronization. After connection, the switch periodically sends location and attachment notifications to the MSE. Any link
up or link down events detected during an interval are aggregated and sent at the end of the interval.
When the switch determines the presence or absence of a device on a link-up or link-down event, it obtains the client-specific
information such as the MAC address, IP address, and username. If the client is LLDP-MED- or CDP-capable, the switch obtains
the serial number and UDI through the LLDP-MED location TLV or CDP.
Depending on the device capabilities, the switch obtains this client information at link up:
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Slot and port specified in port connection
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MAC address specified in the client MAC address
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IP address specified in port connection
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802.1X username if applicable
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Device category is specified as a wired station
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State is specified as new
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Serial number, UDI
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Model number
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Time in seconds since the switch detected the association
Depending on the device capabilities, the switch obtains this client information at link down:
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Slot and port that was disconnected
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MAC address
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IP address
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802.1X username if applicable
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Device category is specified as a wired station
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State is specified as delete
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Serial number, UDI
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Time in seconds since the switch detected the disassociation
When the switch shuts down, it sends an attachment notification with the state delete and the IP address before closing the NMSP connection to the MSE. The MSE interprets this notification as disassociation
for all the wired clients associated with the switch.
If you change a location address on the switch, the switch sends an NMSP location notification message that identifies the
affected ports and the changed address information.