Link Layer Discovery Protocol (LLDP) – The Layer 2 network discovery protocol described in the
IEEE 802.1AB standard, Station and Media Access Control Connectivity Discovery. This protocol
enables a station to advertise its capabilities to, and to discover, other LLDP-enabled stations in the
same 802 LAN segments.

LLDP Agent – The protocol entity that implements LLDP for a particular IEEE 802 device.
Depending on the configured LLDP operating mode, an LLDP agent can send and receive LLDP
advertisements (frames), or send LLDP advertisements only, or receive LLDP advertisements only.

LLDPDU (LLDP Data Unit) – A unit of information in an LLDP packet that consists of a sequence of
short variable length information elements, known as TLVs.

MIB (Management Information Base) – A virtual database that identifies each manageable object
by its name, syntax, accessibility, and status, along with a text description and unique object
identifier (OID). The database is accessible by a Network Management System (NMS) using a
management protocol such as the Simple Network Management Protocol (SNMP).

Network Connectivity Device – A forwarding 802 LAN device, such as a router, switch, or wireless
access point. The terms Station and Network Connectivity Device are used interchangeably in this
chapter and mean the same thing. See Station, below.

Station – A node in a network. It generally refers to a client PC (workstation) rather than a server,
but may include both. Also referred to as Network Connectivity Device, this is a forwarding 802 LAN
device, such as a router, switch, or wireless access point.

TLV (Type-Length-Value) – An information element in an LLDPDU that describes the type of
information being sent, the length of the information string, and the value (actual information) that
will be transmitted.

TTL (Time-to-Live) – Specifies the length of time that the receiving device should maintain the
information acquired through LLDP in its MIB.