Recruiting new tor relays with BRAIDS

Abstract

Tor, a distributed Internet anonymizing system, relies on volunteers who run dedicated relays. Other than altruism, these volunteers have no incentive to run relays, causing a large disparity between the number of users and available relays. We introduce BRAIDS, a set of practical mechanisms that encourages users to run Tor relays, allowing them to earn credits redeemable for improved performance of both interactive and non-interactive Tor traffic. These performance incentives will allow Tor to support increasing resource demands with almost no loss in anonymity: BRAIDS is robust to well-known attacks. Using a simulation of 20,300 Tor nodes, we show that BRAIDS allows relays to achieve 75% lower latency than non-relays for interactive traffic, and 90% higher bandwidth utilization for non-interactive traffic.

Proof-of-Work as Anonymous Micropayment: Rewarding a Tor Relay

“…Jansen, Hopper, and Kim [16] developed BRAIDS, a scheme in which users "pay" relays with tickets. Double spending is prevented by that tickets are "relayspecific".…”

“…Third, it should not rely on secure bandwidth measurement mechanisms. Fourth, it should not involve a central bank as in [16]. Sixth, the scheme should not require from users to run a Tor relay in order to get improved service.…”

“…Tickets are issued by relays using blind signatures [5] and exchanged between users and relays over anonymous Tor circuits. Unlike [16] we do not use any bank entity and tickets are blind-signed by relays themselves. Setup.…”

Challenges in Protecting Tor Hidden Services from Botnet Abuse

“…-Relay descriptors could include "puzzle specifications" that describe what the challenge will be for a given time period, requiring a method to prevent "precomputing" a batch of payments before the time period; how to solve this problem is an open question. -Another method would use an extra trusted server that verifies resource expenditures and issues relay-and time period-specific signed tokens, similar to ripcoins [12] or the tokens in BRAIDS [10]. Using blinded tokens would limit the trust required in the server so that it can't compromise anonymity, and relay-specificity would allow each relay to verify that tokens aren't double-spent.…”

Research on Anonymous Network Topology Analysis

“…Later, Jansen et al [4] proposed BRAIDS, which encourage users to run Tor relays by introducing relay-specific tickets for service accounting. The tickets are embedded into Tor cells to request some sort of service，such as low-latency service, high-throughput service, and normal service.…”