Dell Force10 E1200i FTOS Version 8.4.1.5 Configuration Guide for ExaScale - Page 566

www.dell.com | support.dell.com TLVs are encapsulated in a frame called an LLDP Data Unit (LLDPDU) (Figure 29-2), which is transmitted from one LLDP-enabled device to its LLDP-enabled neighbors. LLDP is a one-way protocol. LLDP-enabled devices (LLDP agents) can transmit and/or receive advertisements, but they cannot solicit and do not respond to advertisements. There are five types of TLVs. All types are mandatory in the construction of an LLDPDU except Optional TLVs. The inclusion of individual Optional TLVs is user configurable. Table 29-1. Type, Length, Value (TLV) Types Type TLV Description 0 End of LLDPDU Marks the end of an LLDPDU 1 Chassis ID An administratively assigned name that identifies the LLDP agent 2 Port ID An administratively assigned name that identifies a port through which TLVs are sent and received 3 Time to Live A value that tells the receiving agent how long the information contained in the TLV Value field is valid - Optional Includes sub-types of TLVs that advertise specific configuration information. These sub-types are Management TLVs, IEEE 802.1, IEEE 802.3, and TIA-1057 Organizationally Specific TLVs. Figure 29-2. LLDPDU Frame Preamble Start Frame Destination MAC Source MAC Delimiter (01:80:C2:00:00:0E) Ethernet Type (0x88CC) LLDPDU Padding FCS TLV 1 Chassis ID TLV 2 Port ID TLV 3 Port Description TLV 4 TLV 5 TLV 6 TLV 7 TLV 127 TLV 0 System Name System Description System Capabilities Management Addr Organizationally Specific End of LLDPDU fnC0047mp Optional TLVs FTOS supports the following optional TLVs: • Management TLVs • IEEE 802.1 and 802.3 Organizationally Specific TLVs • TIA-1057 Organizationally Specific TLVs Management TLVs A Management TLV is an Optional TLVs sub-type. This kind of TLV contains essential management information about the sender. The five types are described in Table 29-2, "Optional TLV Types," in Link Layer Discovery Protocol. 566 | Link Layer Discovery Protocol