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LevelOne GSW-4876 User Manual

Page 159

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C

HAPTER

4

| Configuring the Switch

Link Layer Discovery Protocol

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LLDP Interface Attributes

Port – Port identifier.

Mode – Enables LLDP message transmit and receive modes for LLDP

Protocol Data Units. (Options: Disabled, Enabled - TxRx, Rx only,

Tx only; Default: Disabled)

CDP Aware – Enables decoding of Cisco Discovery Protocol frames.

(Default: Disabled)
If enabled, CDP TLVs that can be mapped into a corresponding field in

the LLDP neighbors table are decoded, all others are discarded. CDP

TLVs are mapped into LLDP neighbors table as shown below:

CDP TLV “Device ID” is mapped into the LLDP “Chassis ID” field.

CDP TLV “Address” is mapped into the LLDP “Management Address”

field. The CDP address TLV can contain multiple addresses, but only

the first address is shown in the LLDP neighbors table.

CDP TLV “Port ID” is mapped into the LLDP “Port ID” field.

CDP TLV “Version and Platform” is mapped into the LLDP “System

Description” field.

Both the CDP and LLDP support “system capabilities,” but the CDP

capabilities cover capabilities that are not part of LLDP. These

capabilities are shown as “others” in the LLDP neighbors table.

If all ports have CDP awareness disabled, the switch forwards CDP

frames received from neighbor devices. If at least one port has CDP

awareness enabled, all CDP frames are terminated by the switch.
When CDP awareness for a port is disabled, the CDP information is not

removed immediately, but will be removed when the hold time is

exceeded.

Optional TLVs - Configures the information included in the TLV field of

advertised messages.

Port Descr – 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.

Sys Name – 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, see

page 45

.

Sys Descr – 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.

Sys Capa – 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.