HP V1910, User Manual

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LLDP configuration
Background
In a heterogeneous network, it is important that different types of network devices from different vendors can
discover one other and exchange configuration for interoperability and management sake. To ensure
compatibility, a standard configuration exchange platform was created.
The IETF drafted the Link Layer Discovery Protocol (LLDP) in IEEE 802.1AB. The protocol operates on the
data link layer to exchange device information between directly connected devices. With LLDP, a device
sends local device information as TLV (type, length, and value) triplets in LLDP Data Units (LLDPDUs) to the
directly connected devices, and at the same time, stores the device information received in LLDPDUs sent
from the LLDP neighbors in a standard management information base (MIB). It allows a network
management system to quickly detect and identify Layer 2 network topology changes.
Basic concepts
LLDPDUs
LLDP sends device information in LLDPDUs. LLDPDUs are encapsulated in Ethernet II or Subnetwork Access
Protocol (SNAP) frames.
Table 56 Ethernet II-encapsulated LLDPDU format
b.
Ethernet II-encapsulated LLDPDU format
2.
Fields in an Ethernet II encapsulated LLDPDU
Field Description
Destination MAC address
The MAC address to which the LLDPDU is advertised. It is fixed to
0x0180-C200-000E, a multicast MAC address.
Source MAC address
The MAC address of the sending port. If the port does not have a MAC
address, the MAC address of the sending bridge is used.
Type The Ethernet type for the upper layer protocol. It is 0x88CC for LLDP.
Data LLDPDU.