An engineer encounters third-party devices that do not support Cisco Discovery Protocol. What must be configured on the network to allow device discovery?

TFTP (Trivial File Transfer Protocol) is used for transferring configuration files or firmware, not for device discovery or neighbor advertising.

LACP (Link Aggregation Control Protocol) is used to bundle multiple physical network links into a single logical link, increasing bandwidth and redundancy, not for device discovery.

Link Layer Discovery Protocol (LLDP) is an industry-standard, vendor-neutral protocol that allows network devices to advertise their identity, capabilities, and neighbors on a local area network. It serves the same purpose as Cisco Discovery Protocol (CDP) but is interoperable with third-party devices.

SNMP (Simple Network Management Protocol) is used for managing and monitoring network devices but does not provide the automatic, layer 2 neighbor discovery functionality that CDP or LLDP offers.