To query the DHT for a topic like "Counterfeit Currency," your client must broadcast that interest to several peers. An adversary running many DHT nodes (a Sybil attack) could map which IPs (or Tor circuits) are looking up which illegal topics. The 2.1 roadmap promises "private information retrieval" (PIR) to solve this, but it is not yet implemented.
| Threat | Legacy Hidden Wiki | Topic Links 2.0 Onion | | :--- | :--- | :--- | | | Detected only after the fact | Services pre-sign existence; revocation alerts users immediately | | Phishing | Common; relies on user vigilance | Name verification via linked signatures (PKI for onion sites) | | MITM Attacks | Trivial with rogue exit nodes (clearnet mirrors) | Impossible; end-to-end between Tor clients and services | | Censorship (Sybil) | Central admin deletes links | DHT requires 51% of storage peers to censor a link | Topic Links 2.0 Onion
As one anonymous contributor posted on a DHT peer note: "The Hidden Wiki was a map drawn in sand at low tide. Topic Links 2.0 is a constellation. You cannot erase a constellation." To query the DHT for a topic like
Furthermore, because the Link Sets are signed by maintainers who themselves use client-side certificates, you can build a "web of trust" over time. If you have verified that alice.onion signed the "Finance" topic set, and that set includes bank.onion , you have transitive trust. No darknet technology emerges without debate. Topic Links 2.0 has faced significant pushback, particularly from old-guard hidden wiki operators and law enforcement agencies. | Threat | Legacy Hidden Wiki | Topic Links 2
You must enable HiddenServiceSingleHopMode and DHTClient in your torrc file (advanced users only) to participate in the DHT.