The server node contains the configuration of the plcd software. plcd is built around the concept of a thread. Every instance of plcd has at least an 'engine' thread which manages the communication path between 0 or more worker threads. The engine thread also handles macro evaluation and expansion.

Worker threads are one of two types, 'net' or 'powerline', and any number of each of these thread types can be initialized, so it is very possible that in the future, plcd will be able to translate commands or events from one protocol to others. Each thread type has its own configuration parameters.