Topology Discovery

This dialog enables you to activate/deactivate the function for Topology Recognition (LLDP) and to display the LLDP information received in the form of 2 tables grouped according to general LLDP information and LLDP-MED information.

LLDP Information from Neighbor Devices

The table on the “LLDP” tab page shows you the collected LLDP information for neighboring devices. This information enables the network management station to map the structure of your network.

Activating “Display FDB entries” below the table allows you to add entries for devices without active LLDP support to the table. In this case, the device also includes information from its FDB (forwarding database).

The table shows you which LLDP-MED information the device received on its ports from other devices.

Tab. Topology discovery (LLDP information)

Parameters

Meaning

“Port”

Port identification using module and port numbers of the device, e.g. 2.1 for port one of module two.

Neighbor Identifier

Chassis ID of the neighboring device. This can be the basis MAC address of the neighboring device, for example.

Neighbor IP Address

Management address of the neighboring device. This can be an IPv4 address, for example.

Neighbor Port Description

Port description of the neighboring device. The port description is an alphanumeric string.

Neighbor System Name

System name of the neighboring device. The system name is an alphanumeric string.

Neighbor ‍System Description

System description of the neighbor device, according to IEEE 802.1AB.


If several devices are connected to one port, for example via a hub, the table will contain one line for each connected device.

When devices both with and without an active topology discovery function are connected to a port, the topology table hides the devices without active topology discovery.

When only devices without active topology recognition are connected to a port, the table will contain one line for this port to represent all devices. This line contains the number of connected devices.

You can find the MAC addresses of devices, which the topology table hides for clarity's sake, in the address table (FDB), (refer Filter for MAC addresses).

LLDP-MED (Media Endpoint Discovery)

The card index “LLDP-MED” tabs table shows you the LLDP-MED information about neighboring devices collected. This requires that both the LLDP-MED function and the LLDP function (refer LLDP Information from Neighbor Devices) are activated.

The device supports the following sub-types in the network connectivity messages:

The table shows you which LLDP-MED information the device received on its ports from other devices.

Tab. Topology discovery (LLDP-MED information)

Parameters

Meaning

“Port”

Port identification using module and port numbers of the device, e.g. 2.1 for port one of module two.

Device Class

LLDP-MED device class of the remote device:

  • 0: undefined (properties not included in any defined class)

  • 1: Terminal Device Class I

  • 2: Terminal Device Class II

  • 3: Terminal Device Class III

  • 4: Network Device

VLAN ID

VLAN ID of the network policy for the remote device's port (0 - 4094), 0: Priority-Tagged Frames

Priority

Layer 2 (IEEE 802.1p) priority of the network policy for the remote device's port (0 - 7)

DSCP

Value of Differentiated Services Code Point (according to RFC 2474 and 2475) of the network policy for the remote device's port (0 - 63)

Unknown Bit Status

  • true: The network policy for the remote device's application type is currently unknown.
    The values for VLAN ID, Priority and DSCP are meaningless in this instance.

  • false: The network policy for the remote device's application type is known.

Tagged Bit Status

  • true: The remote device's application uses VLAN-tagged frames

  • false: The remote device's application uses untagged frames or does not support port VLAN-based operation.
    The values for VLAN ID and Priority are meaningless in this instance.

Hardware Revision

Manufacturer-specific string including the terminal device's hardware version (max. 32 characters)

Firmware Revision

Manufacturer-specific string including the terminal device's firmware version (max. 32 characters)

Software Revision

Manufacturer-specific string including the terminal device's software version (max. 32 characters)

Serial Number

Manufacturer-specific string including the terminal device's serial number (max. 32 characters)

Manufacturer's Name

Manufacturer-specific string including the name of terminal device's manufacturer (max. 32 characters)

Model Name

Manufacturer-specific string including the name of terminal device's model (max. 32 characters)

Asset ID

Manufacturer-specific string including the ID for the terminal device's inventory (max. 32 characters)


Note: When you activate the LLDP-MED function, the Switch sends out information about its properties in the form of LLDP-MED frames. Information about the voice VLANs configured in the Switch also pertain to it (refer Voice VLAN). As a consequence, activate the LLDP-MED function if you want to operate the Switch devices, e.g. a VoIP telephone via plug-and-play, because both devices require information about their respective neighboring devices on that account.

Buttons

Tab. Buttons (Forts.)

Button

Meaning

“Set”

Transfers the changes to the volatile memory (RAM) of the device. To permanently save the changes afterwards, you open the Basic Settings:Load/Save dialog and click “Save”.

“Reload”

Updates the fields with the values that are saved in the volatile memory (RAM) of the device.

“Help”

Opens the online help.