A system for assigning addresses to a plurality of communication nodes coupled via a power line is disclosed. Each of the plurality of communication nodes includes a current sensor. The plurality of communication nodes includes one master communication node and the master communication node is configured to start an auto-addressing process by asking the each of the plurality of communication nodes to sink a preselect amount of current and measure current, through the current sensor, flowing through the powerline under the each of the plurality of communication nodes. A first communication node in the plurality of communication nodes that does not measure any current flowing under the first communication node is assigned a first address.