# Detecting IP Device

When an IP device registers with a controller, the controller queries the IP device for its Layer 2 MAC address or Chassis ID and port. If the controller detects a change in location when a DN re-registers, it stores both the previous and current locations.

If the system cannot determine the MAC or Chassis ID and port, it displays one of the following messages in the location fields:

Message | Cause | Corrective Action
"Unknown" | The firmware load of the device may be out-of-date and cannot detect LLDP and/or STP and/or CDP data. | Check the posted Release Notes (RN) on Mitel OnLine for the current "Main Load" delivered with this release. If required, upgrade the IP device firmware.
"Not supported" | LLDP and/or STP and/or CDP is not enabled on the Layer 2 switch. | Enable LLDP and/or STP and/or CDP on the switch. If the switch does not support these protocols, contact the supplier for upgrade information.

The following actions will generate form entries and Device Detection logs:

Action | Result
A user changes a DN the System Administration tool. | When the changed DN registers with the controller, the system records it as a first-time registration.
A user moves a DN from one controller to another . | When the moved DN registers with the other controller, the system records it as a first-time registration.
A technician replaces a Layer 2 switch. | When a DN reregisters with the controller, it provides the new Layer 2 switch's MAC address or Chassis ID. The system detects the change in MAC address or Chassis ID and records it as a moved IP device.
A network administrator enables STP or an IP device loads firmware that supports STP. | On registration, the DN provides a MAC address and port. The system detects a change in network location ("Not Supported" or "Unknown" to a valid MAC address and port) and records it as a moved IP device.

## Examples of Device Move

The following examples show the information displayed for registered IP devices:

| An IP device with directory number 46008 first registered with the controller on January 4th, 2004 at 10:43:21 AM. The system recorded the following MAC address and port as the device's network location: 00:01:E7:0C:21:32, port 14. Because the IP device has not previously registered, the system sets the Move Acknowledged flag to "Not Applicable". The entry is not listed in the Device Connectivity-Moved form.
| An IP device with directory number 47084 registered with the controller on January 5th, 2004 at 1:45:13 PM and reported the following MAC address and port as its network location: 00:80:2D:7C:D0:61, port 9. The system detected a change in port from 7 to 9, updated the entry for DN 47084, and set the Move Acknowledged flag to "No". This entry is listed in the Device Connectivity-Moved form.
| An IP device with directory number 47111 registered with the controller on January 6th, 2004 at 11:26:56 AM and reported the following MAC address and port as its network location: 00:30:85:A0:D4:4F, port 24. The system detected a change in MAC address and port, updated the entry for DN 47111, and set the Move Acknowledged flag to "No". This entry is listed in the Device Connectivity-Moved form.
| An IP device with directory number 51070 registered with the controller on January 7th, 2004 at 9:42:01 AM. and did not report a MAC address and port. ("Not Supported" indicates that STP was not enabled on the network.) When it previously registered, the device did not report a network location. ("Unknown" indicates that the IP device's firmware does not support STP.) The system detected a change in previous and current values ("unknown" to "Not Supported"), updated the entry for DN 51070, and set the Move Acknowledged flag to "No". This entry is listed in the Device Connectivity-Moved form.