Link Layer Discovery Protocol (LLDP) is used to discover basic information about neighboring devices on the local broadcast domain. LLDP is a Layer 2 protocol that uses periodic broadcasts to advertise information about the sending device. Advertised information is represented in Type Length Value (TLV) format according to the IEEE 802.1ab standard, and can include details such as device identification, capabilities and configuration settings. LLDP also defines how to store and maintain information gathered about the neighboring network nodes it discovers.
Link Layer Discovery Protocol - Media Endpoint Discovery (LLDP-MED) is an extension of LLDP intended for managing endpoint devices such as Voice over IP phones and network switches. The LLDP-MED TLVs advertise information such as network policy, power, inventory, and device location details. LLDP and LLDP-MED information can be used by SNMP applications to simplify troubleshooting, enhance network management, and maintain an accurate network topology.
Use the Administration > LLDP (Configure Global) page to set attributes for general functions such as globally enabling LLDP on the switch, setting the message ageout time, and setting the frequency for broadcasting general advertisements or reports about changes in the LLDP MIB.
Enables LLDP globally on the switch. (Default: Enabled)
Configures the periodic transmit interval for LLDP advertisements. (Range: 5-32768 seconds; Default: 30 seconds)
Configures the time-to-live (TTL) value sent in LLDP advertisements as shown in the formula below. (Range: 2-10; Default: 4)
The time-to-live tells the receiving LLDP agent how long to retain all information pertaining to the sending LLDP agent if it does not transmit updates in a timely manner.
TTL in seconds is based on the following rule: minimum value ((Transmission Interval * Holdtime Multiplier), or 65535)
Therefore, the default TTL is 4*30 = 120 seconds.
Configures a delay between the successive transmission of advertisements initiated by a change in local LLDP MIB variables. (Range: 1-8192 seconds; Default: 2 seconds)
The transmit delay is used to prevent a series of successive LLDP transmissions during a short period of rapid changes in local LLDP MIB objects, and to increase the probability that multiple, rather than single changes, are reported in each transmission.
This attribute must comply with the rule:
(4 * Delay Interval) <= Transmission Interval
Configures the delay before attempting to re-initialize after LLDP ports are disabled or the link goes down. (Range: 1-10 seconds; Default: 2 seconds)
When LLDP is re-initialized on a port, all information in the remote systems LLDP MIB associated with this port is deleted.
Configures the allowed interval for sending SNMP notifications about LLDP MIB changes. (Range: 5-3600 seconds; Default: 5 seconds)
This parameter only applies to SNMP applications which use data stored in the LLDP MIB for network monitoring or management.
Information about changes in LLDP neighbors that occur between SNMP notifications is not transmitted. Only state changes that exist at the time of a notification are included in the transmission. An SNMP agent should therefore periodically check the value of lldpStatsRemTableLastChangeTime to detect any lldpRemTablesChange notification-events missed due to throttling or transmission loss.
Configures the amount of LLDP MED Fast Start LLDPDUs to transmit during the activation process of the LLDP-MED Fast Start mechanism. (Range: 1-10 packets; Default: 4 packets)
The MED Fast Start Count parameter is part of the timer which ensures that the LLDP-MED Fast Start mechanism is active for the port. LLDP-MED Fast Start is critical to the timely startup of LLDP, and therefore integral to the rapid availability of Emergency Call Service.
Use the Administration > LLDP (Configure Interface - Configure General) page to specify the message attributes for individual interfaces, including whether messages are transmitted, received, or both transmitted and received, whether SNMP notifications are sent, and the type of information advertised.
Enables LLDP message transmit and receive modes for LLDP Protocol Data Units. (Options: Tx only, Rx only, TxRx, Disabled; Default: TxRx)
Enables the transmission of SNMP trap notifications about LLDP and LLDP-MED changes. (Default: Enabled)
This option sends out SNMP trap notifications to designated target stations at the interval specified by the Notification Interval in the preceding section. Trap notifications include information about state changes in the LLDP MIB (IEEE 802.1AB), the LLDP-MED MIB (ANSI/TIA-1057), or vendor-specific LLDP-EXT-DOT1 and LLDP-EXT-DOT3 MIBs.
Information about additional changes in LLDP neighbors that occur between SNMP notifications is not transmitted. Only state changes that exist at the time of a trap notification are included in the transmission. An SNMP agent should therefore periodically check the value of lldpStatsRemTableLastChangeTime to detect any lldpRemTablesChange notification-events missed due to throttling or transmission loss.
Enables the transmission of SNMP trap notifications about LLDP-MED changes. (Default: Disabled)
Configures basic information included in the TLV field of advertised messages.
The management address protocol packet includes the IPv4 address of the switch. If no management address is available, the address should be the MAC address for the CPU or for the port sending this advertisement. (Default: Enabled)
The management address TLV may also include information about the specific interface associated with this address, and an object identifier indicating the type of hardware component or protocol entity associated with this address. The interface number and OID are included to assist SNMP applications in the performance of network discovery by indicating enterprise specific or other starting points for the search, such as the Interface or Entity MIB.
Since there are typically a number of different addresses associated with a Layer 3 device, an individual LLDP PDU may contain more than one management address TLV.
Every management address TLV that reports an address that is accessible on a port and protocol VLAN through the particular port should be accompanied by a port and protocol VLAN TLV that indicates the VLAN identifier (VID) associated with the management address reported by this TLV.
The port description is taken from the ifDescr object in RFC 2863, which includes information about the manufacturer, the product name, and the version of the interface hardware/software. (Default: Enabled)
The system capabilities identifies the primary function(s) of the system and whether or not these primary functions are enabled. The information advertised by this TLV is described in IEEE 802.1AB. (Default: Enabled)
The system description is taken from the sysDescr object in RFC 3418, which includes the full name and version identification of the system's hardware type, software operating system, and networking software. (Default: Enabled)
The system name is taken from the sysName object in RFC 3418, which contains the system‘s administratively assigned name. To configure the system name. (Default: Enabled)
Configures IEEE 802.1 information included in the TLV field of advertised messages..
The protocols that are accessible through this interface. (Default: Enabled)
The port‘s default VLAN identifier (PVID) indicates the VLAN with which untagged or priority-tagged frames are associated. (Default: Enabled)
The name of all VLANs to which this interface has been assigned. (Default: Enabled)
The port-based protocol VLANs configured on this interface. (Default: Enabled)
Configures IEEE 802.3 information included in the TLV field of advertised messages.
The link aggregation capabilities, aggregation status of the link, and the IEEE 802.3 aggregated port identifier if this interface is currently a link aggregation member. (Default: Enabled)
The maximum frame size. (Default: Enabled)
The MAC/PHY configuration and status which includes information about auto-negotiation support/capabilities, and operational Multistation Access Unit (MAU) type. (Default: Enabled)
Power-over-Ethernet capabilities, including whether or not PoE is supported, currently enabled, if the port pins through which power is delivered can be controlled, the port pins selected to deliver power, and the power class. (Default: Enabled)
Configures general information included in the MED TLV field of advertised messages.
This option advertises LLDP-MED TLV capabilities, allowing Media Endpoint and Connectivity Devices to efficiently discover which LLDP-MED related TLVs are supported on the switch. (Default: Enabled)
This option advertises extended Power-over-Ethernet capability details, such as power availability from the switch, and power state of the switch, including whether the switch is operating from primary or backup power (the Endpoint Device could use this information to decide to enter power conservation mode). Note that this device does not support PoE capabilities. (Default: Enabled)
This option advertises device details useful for inventory management, such as manufacturer, model, software version and other pertinent information. (Default: Enabled)
This option advertises location identification details. (Default: Enabled)
This option advertises network policy configuration information, aiding in the discovery and diagnosis of VLAN configuration mismatches on a port. Improper network policy configurations frequently result in voice quality degradation or complete service disruption. (Default: Enabled)
Configures information for the location of the attached device included in the MED TLV field of advertised messages, including the country and the device type.
The two-letter ISO 3166 country code in capital ASCII letters. (Example: DK, DE or US)
The type of device to which the location applies:
Location of DHCP server.
Location of network element closest to client.
Location of client. (This is the default.)
Use the Administration > LLDP (Configure Interface – Add CA-Type) page to specify the physical location of the device attached to an interface.
Use the Civic Address type (CA-Type) to advertise the physical location of the device attached to an interface, including items such as the city, street number, building and room information. The address location is specified as a type and value pair, with the civic address type defined in RFC 4776.
Any number of CA type and value pairs can be specified for the civic address location, as long as the total does not exceed 250 characters.
Descriptor of the data civic address value. (Range: 0-255)
Description of a location. (Range: 1-32 characters)
Use the Administration > LLDP (Show Local Device Information) page to display information about the switch, such as its MAC address, chassis ID, management IP address, and port information.
General Settings
Identifies the chassis containing the IEEE 802 LAN entity associated with the transmitting LLDP agent. There are several ways in which a chassis may be identified and a chassis ID subtype is used to indicate the type of component being referenced by the chassis ID field.
An octet string indicating the specific identifier for the particular chassis in this system.
A string that indicates the system‘s administratively assigned name.
A textual description of the network entity.
The capabilities that define the primary function(s) of the system.
The primary function(s) of the system which are currently enabled.
The management address associated with the local system. If no management address is available, the address should be the MAC address for the CPU or for the port sending this advertisement.
Interface Settings
The attributes listed below apply to both port and trunk interface types. When a trunk is listed, the descriptions apply to the first port of the trunk.
A string that indicates the port or trunk description. If RFC 2863 is implemented, the ifDescr object should be used for this field.
A string that contains the specific identifier for the port or trunk from which this LLDPDU was transmitted.
Interface Details
The attributes listed below apply to both port and trunk interface types. When a trunk is listed, the descriptions apply to the first port of the trunk.
Local interface on this switch.
There are several ways in which a port may be identified. A port ID subtype is used to indicate how the port is being referenced in the Port ID TLV.
A string that contains the specific identifier for the local interface based on interface subtype used by this switch.
A string that indicates the port or trunk description. If RFC 2863 is implemented, the ifDescr object should be used for this field.
A string that indicates the port or trunk description. If RFC 2863 is implemented, the ifDescr object should be used for this field.
The supported set of capabilities that define the primary function(s) of the interface:
LLDP-MED Capabilities
Network Policy
Location Identification
Extended Power via MDI - PSE
Extended Power via MDI - PD
Inventory
Use the Administration > LLDP (Show Remote Device Information) page to display information about devices connected directly to the switch‘s ports which are advertising information through LLDP, or to display detailed information about an LLDP-enabled device connected to a specific port on the local switch.
Port
The local port to which a remote LLDP-capable device is attached.
An octet string indicating the specific identifier for the particular chassis in this system.
A string that contains the specific identifier for the port from which this LLDPDU was transmitted.
A string that indicates the system‘s administratively assigned name.
Port Details
Port identifier on local switch.
Index of remote device attached to this port.
The local port to which a remote LLDP-capable device is attached.
Identifies the chassis containing the IEEE 802 LAN entity associated with the transmitting LLDP agent. There are several ways in which a chassis may be identified and a chassis ID subtype is used to indicate the type of component being referenced by the chassis ID field.
An octet string indicating the specific identifier for the particular chassis in this system.
A string that indicates the system‘s assigned name.
A textual description of the network entity.
Indicates the basis for the identifier that is listed in the Port ID field.
A string that indicates the port‘s description. If RFC 2863 is implemented, the ifDescr object should be used for this field.
A string that contains the specific identifier for the port from which this LLDPDU was transmitted.
The capabilities that define the primary function(s) of the system.
The primary function(s) of the system which are currently enabled.
The management addresses for this device. Since there are typically a number of different addresses associated with a Layer 3 device, an individual LLDP PDU may contain more than one management address TLV.
If no management address is available, the address should be the MAC address for the CPU or for the port sending this advertisement.
Port Details - 802.1 Extension Information
The port's default VLAN identifier (PVID) indicates the VLAN with which untagged or priority-tagged frames are associated.
The port-based and protocol-based VLANs configured on this interface, whether the given port (associated with the remote system) supports port and protocol VLANs, and whether the port and protocol VLANs are enabled on the given port associated with the remote system.
VLAN names associated with a port.
Information about particular protocols that are accessible through a port. This object represents an arbitrary local integer value used by this agent to identify a particular protocol identity, and an octet string used to identify the protocols associated with a port of the remote system.
Port Details - 802.3 Extension Port Information
Shows whether the given port (associated with remote system) supports auto-negotiation.
The value (bitmap) of the ifMauAutoNegCapAdvertisedBits object (defined in IETF RFC 3636) which is associated with a port on the remote system.
Shows whether port auto-negotiation is enabled on a port associated with the remote system.
An integer value that indicates the operational MAU type of the sending device. This object contains the integer value derived from the list position of the corresponding dot3MauType as listed in IETF RFC 3636 and is equal to the last number in the respective dot3MauType OID.
Port Details - 802.3 Extension Power Information
The port Class of the given port associated with the remote system (PSE - Power Sourcing Equipment or PD - Powered Device).
Shows whether MDI power is enabled on the given port associated with the remote system.
"Signal" means that the signal pairs only are in use, and "Spare" means that the spare pairs only are in use.
Shows whether MDI power is supported on the given port associated with the remote system.
Indicates whether the pair selection can be controlled for sourcing power on the given port associated with the remote system.
This classification is used to tag different terminals on the Power over LAN network according to their power consumption. Devices such as IP telephones, WLAN access points and others, will be classified according to their power requirements.
Port Details - 802.3 Extension Trunk Information
Shows if the remote port is not in link aggregation state and/or it does not support link aggregation.
The current aggregation status of the link.
This object contains the IEEE 802.3 aggregated port identifier, aAggPortID (IEEE 802.3-2002, 30.7.2.1.1), derived from the ifNumber of the ifIndex for the port component associated with the remote system. If the remote port is not in link aggregation state and/or it does not support link aggregation, this value should be zero.
Port Details - 802.3 Extension Frame Information
An integer value indicating the maximum supported frame size in octets on the port component associated with the remote system.
Port Details - LLDP-MED Capability
Any of the following categories of endpoint devices:
Class 1 - The most basic class of endpoint devices.
Class 2 - Endpoint devices that supports media stream capabilities.
Class 3 - Endpoint devices that directly supports end users of the IP communication systems.
Network Connectivity Device - Devices that provide access to the IEEE 802 based LAN infrastructure for LLDP-MED endpoint devices. These may be any LAN access device including LAN switch/router, IEEE 802.1 bridge, IEEE 802.3 repeater, IEEE 802.11 wireless access point, or any device that supports the IEEE 802.1AB and MED extensions defined by this Standard and can relay IEEE 802 frames via any method.
The supported set of capabilities that define the primary function(s) of the port:
LLDP-MED Capabilities
Network Policy
Location Identification
Extended Power via MDI - PSE
Extended Power via MDI - PD
Inventory
The set of capabilities that define the primary function(s) of the port which are currently enabled.
Port Details - Network Policy
The primary application(s) defined for this network policy:
Voice
Voice Signaling
Guest Signaling
Guest Voice Signaling
Softphone Voice
Video Conferencing
Streaming Video
Video Signaling
Indicates whether the specified application type is using a tagged or untagged VLAN.
The Layer 2 priority to be used for the specified application type. This field may specify one of eight priority levels (0-7), where a value of 0 represents use of the default priority.
Indicates that an endpoint device wants to explicitly advertise that this policy is required by the device, but is currently unknown.
The VLAN identifier (VID) for the port as defined in IEEE 802.1Q. A value of zero indicates that the port is using priority tagged frames, meaning that only the IEEE 802.1D priority level is significant and the default PVID of the ingress port is used instead.
The DSCP value to be used to provide Diffserv node behavior for the specified application type. This field may contain one of 64 code point values (0-63). A value of 0 represents use of the default DSCP value as defined in RFC 2475.
Port Details - Location Identification
Any of these location ID data formats:
Coordinate-based LCI (Location Configuration Information) - Defined in RFC 3825, includes latitude resolution, latitude, longitude resolution, longitude, altitude type, altitude resolution, altitude, and datum.
Civic Address LCI - Includes What, Country code, CA type, CA length and CA value. "What" is described as the field entry "Device entry refers to" under "Configuring LLDP Interface Attributes." The other items and described under "Configuring LLDP Interface Civic-Address."
ECS ELIN - Emergency Call Service Emergency Location Identification Number supports traditional PSAP-based Emergency Call Service in North America.
The two-letter ISO 3166 country code in capital ASCII letters. (Example: DK, DE or US)
The type of device to which the location applies as described for the field entry "Device entry refers to" under "Configuring LLDP Interface Attributes."
Port Details - Extended Power-via-MDI
Power Sourcing Entity (PSE) or Power Device (PD).
Shows power priority for a port. (Unknown, Low, High, Critical)
Shows information based on the type of device:
Unknown, PSE, Local, PSE and Local
Unknown, Primary Power Source, Backup Power Source - Power conservation mode
The total power in watts required by a PD device from a PSE device, or the total power a PSE device is capable of sourcing over a maximum length cable based on its current configuration. This parameter supports a maximum power required or available value of 102.3 Watts to allow for future expansion. (Range: 0 - 102.3 Watts)
Port Details - Inventory
The hardware revision of the end-point device.
The software revision of the end-point device.
The manufacturer of the end-point device.
The asset identifier of the end-point device. End-point devices are typically assigned asset identifiers to facilitate inventory management and assets tracking.
The firmware revision of the end-point device.
The serial number of the end-point device.
The model name of the end-point device.
Use the Administration > LLDP (Show Device Statistics) page to display statistics for LLDP-capable devices attached to the switch, and for LLDP protocol messages transmitted or received on all local interfaces.
General Statistics on Remote Devices
The time the LLDP neighbor entry list was last updated.
The number of LLDP neighbors for which the remote TTL has not yet expired.
The number of LLDP neighbors which have been removed from the LLDP remote systems MIB for any reason.
The number of times which the remote database on this switch dropped an LLDPDU because of insufficient resources.
The number of times that a neighbor‘s information has been deleted from the LLDP remote systems MIB because the remote TTL timer has expired.
Port/Trunk
Number of frames discarded because they did not conform to the general validation rules as well as any specific usage rules defined for the particular TLV.
A count of all LLDPDUs received with one or more detectable errors.
Number of LLDP PDUs received.
Number of LLDP PDUs transmitted.
A count of all TLVs not recognized by the receiving LLDP local agent.
A count of all LLDPDUs received and then discarded due to insufficient memory space, missing or out-of-sequence attributes, or any other reason.
A count of the times that a neighbor‘s information has been deleted from the LLDP remote systems MIB because the remote TTL timer has expired.
Use the Administration > LLDP (Show Device Statistics) page to display statistics for LLDP-capable devices attached to the switch, and for LLDP protocol messages transmitted or received on all local interfaces.
General Statistics on Remote Devices
The time the LLDP neighbor entry list was last updated.
The number of LLDP neighbors for which the remote TTL has not yet expired.
The number of LLDP neighbors which have been removed from the LLDP remote systems MIB for any reason.
The number of times which the remote database on this switch dropped an LLDPDU because of insufficient resources.
The number of times that a neighbor‘s information has been deleted from the LLDP remote systems MIB because the remote TTL timer has expired.
Port/Trunk
Number of frames discarded because they did not conform to the general validation rules as well as any specific usage rules defined for the particular TLV.
A count of all LLDPDUs received with one or more detectable errors.
Number of LLDP PDUs received.
Number of LLDP PDUs transmitted.
A count of all TLVs not recognized by the receiving LLDP local agent.
A count of all LLDPDUs received and then discarded due to insufficient memory space, missing or out-of-sequence attributes, or any other reason.
A count of the times that a neighbor‘s information has been deleted from the LLDP remote systems MIB because the remote TTL timer has expired.