Private peer-to-peer

Private peer-to-peer (P2P) systems are peer-to-peer (P2P) systems that allow only mutually trusted peers to participate. This can be achieved by using a central server such as a Direct Connect hub to authenticate clients. Alternatively, users can exchange passwords or cryptographic keys with friends to form a decentralized network. Private peer-to-peer systems can be divided into friend-to-friend (F2F) and group-based systems. Friend-to-friend systems only allow connections between users who know one another, but may also provide automatic anonymous forwarding. Group-based systems allow any user to connect to any other, and thus they cannot grow in size without compromising their users' privacy. Some software, such as WASTE, can be configured to create either group-based or F2F networks.

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