Efficient use of dynamic host configuration protocol in low power and lossy networks

An apparatus, comprising:

• one or more network interfaces to communicate in a computer network;
• a processor coupled to the network interfaces and adapted to execute one or more processes;
• and
• a memory configured to store a process executable by the processor, the process when executed operable to:
• advertise a route to a border router of the computer network;
• receive a unicasted dynamic host configuration protocol (DHCP) solicit message from a requestor device;
• relay the solicit message to the border router of the network without regard to location of a DHCP server;
• and
• relay a DHCP reply to the requestor device;
• wherein the border router is a root node of a directed acyclic graph (DAG).

A system, comprising:

• a border router for a local computer network, the border router configured to provide access between the local computer network and a global computer network;
• and
• a plurality of devices in the local computer network;
• wherein:
• i) each of the plurality of devices is configured to transmit a unicasted dynamic host configuration protocol (DHCP) solicit message to a neighbor device having a route to the border router as an assumed DHCP relay without regard to location of a DHCP server;
• ii) each of the plurality of devices is configured as a DHCP relay to receive unicasted DHCP solicit messages and relay the solicit message to the border router of the network without regard to location of the DHCP server, and to relay a DHCP reply to a corresponding requestor device;
• wherein the border router is a root node of a directed acyclic graph (DAG).