HP ProCurve 6120G/XG Configuration Manual page 432

Configuring for Network Management Applications
LLDP (Link-Layer Discovery Protocol)
N o t e
Because ProCurve switches do not generate CDP packets, they are not
represented in the CDP data collected by any neighbor devices running CDP.
A switch with CDP disabled forwards the CDP packets it receives from other
devices, but does not store the CDP information from these packets in its own
MIB.
LLDP data transmission/collection and CDP data collection are both enabled
in the switch's default configuration. In this state, an SNMP network
management application designed to discover devices running either CDP or
LLDP can retrieve neighbor information from the switch regardless of whether
LLDP or CDP is used to collect the device-specific information.
Protocol State Packet
CDP Enabled
CDP Disabled
LLDP Enabled
LLDP Disabled No packet
13-84
• The LLDP "System Descr" field maps to CDP's "Version" and "Plat­
form" fields.
• The switch assigns "ChassisType" and "PortType" fields as "local" for
both the LLDP and the CDP advertisements it receives.
• Both LLDP and CDP support the "System Capability" TLV. However,
LLDP differentiates between what a device is capable of supporting
and what it is actually supporting, and separates the two types of
information into subelements of the System Capability TLV. CDP has
only a single field for this data. Thus, when CDP System Capability
data is mapped to LLDP, the same value appears in both LLDP System
Capability fields.
• System Name and Port Descr are not communicated by CDP, and thus
are not included in the switch's Neighbors database.
Generation
1
n/a
n/a
1
Generates and Store inbound LLDP data.
transmits
LLDP packets
out all ports on
the switch.
generation.
Inbound Data Management Inbound Packet Forwarding
Store inbound CDP data.
No storage of CDP data from Floods inbound CDP packets
neighbor devices.
No storage of LLDP data
from neighbor devices.
No forwarding of inbound
CDP packets.
from connected devices to
outbound ports.
No forwarding of inbound
LLDP packets.
No forwarding of inbound
LLDP packets.