Dell PowerConnect 8100 CLI Reference Guide - Page 567

27 LLDP Commands The IEEE 802.1AB standard defines the Link Layer Discovery Protocol (LLDP). This protocol allows stations residing on an 802 LAN to advertise major capabilities, physical descriptions, and management information to physically adjacent devices, allowing a network management system (NMS) to access and display this information. The standard is designed to be extensible, providing for the optional exchange of organizational specific information and data related to other IEEE standards. The base implementation supports only the required basic management set of type length values (TLVs). LLDP is a one-way protocol; there are no request/response sequences. Information is advertised by stations implementing the transmit function. The information is received and processed by stations implementing the receive function. Devices are not required to implement both transmit and receive functions and each function can be enabled or disabled separately by the network manager. PowerConnect supports both the transmit and receive functions in order to support device discovery. The LLDP component transmit and receive functions can be enabled/disabled separately per physical port. By default, both transmit and receive functions are disabled on all ports. The application starts each transmit and receive state machine appropriately based on the configured status and operational state of the port. The transmit function is configurable with respect to packet construction and timing parameters. The required Chassis ID, Port ID, and Time to Live (TTL) TLVs are always included in the Link Layer Discovery Protocol Data Unit (LLDPDU). However, inclusion of the optional TLVs in the management set is configurable by the administrator. By default, they are not included. The transmit function extracts the local system information and builds the LLDPDU based on the specified configuration for the port. In addition, the administrator has control over timing parameters affecting the TTL of LLDPDUs and the interval in which they are transmitted. LLDP Commands 567