https://lists.torproject.org/pipermail/tor-relays/2011-August/000900.html https://lists.torproject.org/pipermail/tor-relays/2011-Augus... If you just config it

https://lists.torproject.org/pipermail/tor-relays/2011-August/000900.html https://lists.torproject.org/pipermail/tor-relays/2011-Augus... If you just config it with PublishServerDescriptor as 0 and someone else knows the IP (middle relays) they will be able to use it. It's essentially a function of not announcing the node to anyone. Edit: And to be clear, priv exit nodes don't prevent the timing attack in the article.