darknet

noun

1. (Internet)A network of computers that can only be accessed using special software, configuration, or authorization, usually characterized by the anonymization of users, participating hosts, or both.

   “Despite all the openness of the Internet, there are still places you cannot saunter into on the Web. You must be invited. These are “darknets”: exclusive peer-to-peer networks in which membership is based on circles of trust, whose activities are veiled from the general public.”