http://ttevhjjsjxz6uqqcjkbig5cycd7n7xv7cmd6f5fcvrqaaa7f3bj36wad.onion/technology/security/pow/index.html
To have their
requests queued with higher priority, attackers would need to solve the client
puzzles with higher and higher effort. Many connection requests, each one with
its own puzzle solution, requires an increasing amount of computing resources,
up to the point that the attacker exhaust their resources or have to invest
more and more with diminishing chance of success.