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Chapter 3. System
Rx only: The switch will not send out LLDP information, but LLDP
information from neighbor units is analyzed.
Tx only: The switch will drop LLDP information received from neighbors, but
will send out LLDP information.
Disabled: The switch will not send out LLDP information, and will drop LLDP
information received from neighbors.
Enabled: the switch will send out LLDP information, and will analyze LLDP
information received from neighbors.
CDP Aware:
Select CDP awareness.
The CDP operation is restricted to decode incoming CDP frames (The switch
doesn't transmit CDP frames). CDP frames are only decoded if LLDP on the
port is enabled.
Only CDP TLVs that can be mapped to a corresponding field in the LLDP
neighbors' table are decoded. All other TLVs are discarded (Unrecognized
CDP TLVs and discarded CDP frames are not shown in the LLDP statistics.).
CDP TLVs are mapped onto LLDP neighbors' table as shown below.
CDP TLV "Device ID" is mapped to the LLDP "Chassis ID" field.
CDP TLV "Address" is mapped to 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 to the LLDP "Port ID" field.
CDP TLV "Version and Platform" is mapped to the LLDP "System
Description" field.
Both the CDP and LLDP support "system capabilities", but the CDP
capabilities cover capabilities that are not part of the 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.
Note: When CDP awareness on a port is disabled the CDP information isn't
removed immediately, but gets when the hold time is exceeded.
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