Cisco IE 4000, Software Configuration Manual

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Cisco Systems, Inc. www.cisco.com
Configuring LLDP, LLDP-MED, and Wired
Location Service
Information About LLDP, LLDP-MED, and Wired Location Service
The Cisco Discovery Protocol (CDP) is a device discovery protocol that runs over Layer 2 (the data link layer) on all
Cisco-manufactured devices (routers, bridges, access servers, and switches). CDP allows network management
applications to automatically discover and learn about other Cisco devices connected to the network.
To support non-Cisco devices and to allow for interoperability between other devices, the switch supports the IEEE
802.1AB Link Layer Discovery Protocol (LLDP). LLDP is a neighbor discovery protocol that is used for network devices
to advertise information about themselves to other devices on the network. This protocol runs over the data-link layer,
which allows two systems running different network layer protocols to learn about each other.
LLDP supports a set of attributes that it uses to discover neighbor devices. These attributes contain type, length, and
value descriptions and are referred to as TLVs. LLDP supported devices can use TLVs to receive and send information
to their neighbors. This protocol can advertise details such as configuration information, device capabilities, and device
identity.
The switch supports these basic management TLVs. These are mandatory LLDP TLVs.

Port description TLV

System name TLV

System description TLV

System capabilities TLV

Management address TLV
These organizationally specific LLDP TLVs are also advertised to support LLDP-MED:

Port VLAN ID TLV ((IEEE 802.1 organizationally specific TLVs)

MAC/PHY configuration/status TLV(IEEE 802.3 organizationally specific TLVs)
Note: A switch stack appears as a single switch in the network. Therefore, LLDP discovers the switch stack, not the
individual stack members.
LLDP-MED
LLDP for Media Endpoint Devices (LLDP-MED) is an extension to LLDP that operates between endpoint devices such as
IP phones and network devices such as switches. It specifically provides support for voice over IP (VoIP) applications and
provides additional TLVs for capabilities discovery, network policy, Power over Ethernet, inventory management and
location information. By default, all LLDP-MED TLVs are enabled.
LLDP-MED supports these TLVs: