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Contents
- Configuring LLDP, LLDP-MED, and Wired Location Service
- Finding Feature Information
- LLDP, LLDP-MED, and Wired Location Service Overview
- LLDP
- LLDP Supported TLVs
- LLDP and Cisco Switch Stacks
- LLDP and Cisco Medianet
- LLDP-MED
- LLDP-MED Supported TLVs
- Wired Location Service
- Default LLDP Configuration
- Configuration Guidelines
- How to Configure LLDP, LLDP-MED, and Wired Location Service
- Enabling LLDP
- Configuring LLDP Characteristics
- Configuring LLDP-MED TLVs
- Configuring Network-Policy TLV
- Configuring Location TLV and Wired Location Service
- Enabling Wired Location Service on the Switch
- Configuration Examples for LLDP, LLDP-MED, and Wired Location Service
- Configuring Network-Policy TLV: Examples
- Monitoring and Maintaining LLDP, LLDP-MED, and Wired Location Service
- Additional References for LLDP, LLDP-MED, and Wired Location Service
Configuring LLDP, LLDP-MED, and Wired Location Service
This module contains the following sections:
- Finding Feature Information
- LLDP, LLDP-MED, and Wired Location Service Overview
- How to Configure LLDP, LLDP-MED, and Wired Location Service
- Configuration Examples for LLDP, LLDP-MED, and Wired Location Service
- Monitoring and Maintaining LLDP, LLDP-MED, and Wired Location Service
- Additional References for LLDP, LLDP-MED, and Wired Location Service
Finding Feature Information
Your software release may not support all the features documented in this module. For the latest feature information and caveats, see the release notes for your platform and software release.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.
Related References
LLDP, LLDP-MED, and Wired Location Service Overview
LLDP
The Cisco Discovery Protocol (CDP) is a device discovery protocol that runs over Layer 2 (the data link layer) on all Cisco-manufactured devices (routers, bridges, access servers, and switches). CDP allows network management applications to automatically discover and learn about other Cisco devices connected to the network.
To support non-Cisco devices and to allow for interoperability between other devices, the switch supports the IEEE 802.1AB Link Layer Discovery Protocol (LLDP). LLDP is a neighbor discovery protocol that is used for network devices to advertise information about themselves to other devices on the network. This protocol runs over the data-link layer, which allows two systems running different network layer protocols to learn about each other.
LLDP Supported TLVs
LLDP supports a set of attributes that it uses to discover neighbor devices. These attributes contain type, length, and value descriptions and are referred to as TLVs. LLDP supported devices can use TLVs to receive and send information to their neighbors. This protocol can advertise details such as configuration information, device capabilities, and device identity.
The switch supports these basic management TLVs. These are mandatory LLDP TLVs.
- Port description TLV
- System name TLV
- System description TLV
- System capabilities TLV
- Management address TLV
These organizationally specific LLDP TLVs are also advertised to support LLDP-MED.
LLDP and Cisco Switch Stacks
A switch stack appears as a single switch in the network. Therefore, LLDP discovers the switch stack, not the individual stack members.
LLDP and Cisco Medianet
When you configure LLDP or CDP location information on a per-port basis, remote devices can send Cisco Medianet location information to the switch. For information, go to http://www.cisco.com/en/US/docs/ios/netmgmt/configuration/guide/nm_cdp_discover.html.
LLDP-MED
LLDP for Media Endpoint Devices (LLDP-MED) is an extension to LLDP that operates between endpoint devices such as IP phones and network devices such as switches. It specifically provides support for voice over IP (VoIP) applications and provides additional TLVs for capabilities discovery, network policy, Power over Ethernet, inventory management and location information. By default, all LLDP-MED TLVs are enabled.
LLDP-MED Supported TLVs
- LLDP-MED capabilities TLV Allows LLDP-MED endpoints to determine the capabilities that the connected device supports and has enabled.
- Network policy TLV Allows both network connectivity devices and endpoints to advertise VLAN configurations and associated Layer 2 and Layer 3 attributes for the specific application on that port. For example, the switch can notify a phone of the VLAN number that it should use. The phone can connect to any switch, obtain its VLAN number, and then start communicating with the call control. By defining a network-policy profile TLV, you can create a profile for voice and voice-signaling by specifying the values for VLAN, class of service (CoS), differentiated services code point (DSCP), and tagging mode. These profile attributes are then maintained centrally on the switch and propagated to the phone.
- Power management TLV Enables advanced power management between LLDP-MED endpoint and network connectivity devices. Allows switches and phones to convey power information, such as how the device is powered, power priority, and how much power the device needs. LLDP-MED also supports an extended power TLV to advertise fine-grained power requirements, end-point power priority, and end-point and network connectivity-device power status. LLDP is enabled and power is applied to a port, the power TLV determines the actual power requirement of the endpoint device so that the system power budget can be adjusted accordingly. The switch processes the requests and either grants or denies power based on the current power budget. If the request is granted, the switch updates the power budget. If the request is denied, the switch turns off power to the port, generates a syslog message, and updates the power budget. If LLDP-MED is disabled or if the endpoint does not support the LLDP-MED power TLV, the initial allocation value is used throughout the duration of the connection. You can change power settings by entering the power inline {auto [max max-wattage] | never | static [max max-wattage]} interface configuration command. By default the PoE interface is in auto mode; If no value is specified, the maximum is allowed (30 W).
- Inventory management TLV Allows an endpoint to send detailed inventory information about itself to the switch, including information hardware revision, firmware version, software version, serial number, manufacturer name, model name, and asset ID TLV.
- Location TLV Provides location information from the switch to the endpoint device. The location TLV can send this information:
- Civic location information Provides the civic address information and postal information. Examples of civic location information are street address, road name, and postal community name information.
- ELIN location information Provides the location information of a caller. The location is determined by the Emergency location identifier number (ELIN), which is a phone number that routes an emergency call to the local public safety answering point (PSAP) and which the PSAP can use to call back the emergency caller.
- Geographic location information Provides the geographical details of a switch location such as latitude, longitude, and altitude of a switch.
- custom location Provides customized name and value of a switch location.
Wired Location Service
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:
- Slot and port specified in port connection
- MAC address specified in the client MAC address
- IP address specified in port connection
- 802.1X username if applicable
- Device category is specified as a wired station
- State is specified as new
- Serial number, UDI
- Model number
- Time in seconds since the switch detected the association
Depending on the device capabilities, the switch obtains this client information at link down:
- Slot and port that was disconnected
- MAC address
- IP address
- 802.1X username if applicable
- Device category is specified as a wired station
- State is specified as delete
- Serial number, UDI
- 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.
Default LLDP Configuration
Configuration Guidelines
- If the interface is configured as a tunnel port, LLDP is automatically disabled.
- If you first configure a network-policy profile on an interface, you cannot apply the switchport voice vlan command on the interface. If the switchport voice vlan vlan-id is already configured on an interface, you can apply a network-policy profile on the interface. This way the interface has the voice or voice-signaling VLAN network-policy profile applied on the interface.
- You cannot configure static secure MAC addresses on an interface that has a network-policy profile.
- For wired location to function, you must first enter the ip device tracking global configuration command.
How to Configure LLDP, LLDP-MED, and Wired Location Service
- Enabling LLDP
- Configuring LLDP Characteristics
- Configuring LLDP-MED TLVs
- Configuring Network-Policy TLV
- Configuring Location TLV and Wired Location Service
Enabling LLDP
SUMMARY STEPS
DETAILED STEPSConfiguring LLDP Characteristics
SUMMARY STEPSYou can configure the frequency of LLDP updates, the amount of time to hold the information before discarding it, and the initialization delay time. You can also select the LLDP and LLDP-MED TLVs to send and receive.
Beginning in privileged EXEC mode, follow these steps to configure the LLDP characteristics.
NoteSteps 2 through 5 are optional and can be performed in any order.
DETAILED STEPSConfiguring LLDP-MED TLVs
SUMMARY STEPSBy default, the switch only sends LLDP packets until it receives LLDP-MED packets from the end device. It then sends LLDP packets with MED TLVs, as well. When the LLDP-MED entry has been aged out, it again only sends LLDP packets.
By using the lldp interface configuration command, you can configure the interface not to send the TLVs listed in the following table.
Table 2 LLDP-MED TLVsBeginning in privileged EXEC mode, follow these steps to enable a TLV on an interface:
DETAILED STEPSConfiguring Network-Policy TLV
SUMMARY STEPSBeginning in privileged EXEC mode, follow these steps to create a network-policy profile, configure the policy attributes, and apply it to an interface.
2. network-policy profile profile number
3. {voice | voice-signaling} vlan [vlan-id {cos cvalue | dscp dvalue}] | [[dot1p {cos cvalue | dscp dvalue}] | none | untagged]
6. network-policy profile number
7. lldp med-tlv-select network-policy
DETAILED STEPSConfiguring Location TLV and Wired Location Service
SUMMARY STEPSBeginning in privileged EXEC mode, follow these steps to configure location information for an endpoint and to apply it to an interface.
2. location {admin-tag string | civic-location identifier {id | host} | elin-location string identifier id | custom-location identifier {id | host} | geo-location identifier {id | host}}
5. location {additional-location-information word | civic-location-id {id | host} | elin-location-id id | custom-location-id {id | host} | geo-location-id {id | host} }
DETAILED STEPSEnabling Wired Location Service on the Switch
SUMMARY STEPSBeginning in privileged EXEC mode, follow these steps to enable wired location service on the switch.
2. nmsp notification interval {attachment | location} interval-seconds
DETAILED STEPSConfiguration Examples for LLDP, LLDP-MED, and Wired Location Service
Configuring Network-Policy TLV: Examples
This example shows how to configure VLAN 100 for voice application with CoS and to enable the network-policy profile and network-policy TLV on an interface:
Switch# configure terminal Switch(config)# network-policy 1 Switch(config-network-policy)# voice vlan 100 cos 4 Switch(config-network-policy)# exit Switch(config)# interface gigabitethernet1/0/1 Switch(config-if)# network-policy profile 1 Switch(config-if)# lldp med-tlv-select network-policyThis example shows how to configure the voice application type for the native VLAN with priority tagging:
Switchconfig-network-policy)# voice vlan dot1p cos 4 Switchconfig-network-policy)# voice vlan dot1p dscp 34Monitoring and Maintaining LLDP, LLDP-MED, and Wired Location Service
Commands for monitoring and maintaining LLDP, LLDP-MED, and wired location service.
Command
Description
Resets the traffic counters to zero.
Deletes the LLDP neighbor information table.
Clears the NMSP statistic counters.
Displays global information, such as frequency of transmissions, the holdtime for packets being sent, and the delay time before LLDP initializes on an interface.
Displays information about a specific neighbor.
You can enter an asterisk (*) to display all neighbors, or you can enter the neighbor name.
Displays information about interfaces with LLDP enabled.
You can limit the display to a specific interface.
Displays information about neighbors, including device type, interface type and number, holdtime settings, capabilities, and port ID.
You can limit the display to neighbors of a specific interface or expand the display for more detailed information.
Displays LLDP counters, including the number of packets sent and received, number of packets discarded, and number of unrecognized TLVs.
Displays the location information for the specified administrative tag or site.
Displays the location information for a specific global civic location.
Displays the location information for an emergency location
Displays the configured network-policy profiles.
Displays the NMSP information
Additional References for LLDP, LLDP-MED, and Wired Location Service
MIBs
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