Dubbed Astoria, the software reduces the number of vulnerable circuits from 58 percent to 5.8 percent. It is the first designed to beat even the asymmetric correlation attacks on Tor which have made it vulnerable.
According to a research paper Astoria differs most significantly from Tor’s default client in how it selects the circuits that connect a user to the network and then to the outside Internet. It is basically an algorithm designed to more accurately predict attacks and then securely select relays that mitigate timing attack opportunities for top-tier adversaries.
Astoria works out how circuits should, according to the researchers, be made “when there are no safe possibilities it can do this even while the Tor users is being watched by the spooks.
.The only thing the spooks have left is the fact that defeating timing attacks against Tor completely isn’t possible because of how Tor is built. However Astoria makes attacks more costly and less likely to succeed.
By choosing relays based on lowering the threat of eavesdropping by autonomous systems and then choosing randomly if no safe passage is possible, Astoria aims to minimize the information gained by an adversary watching an entire circuit.
Astoria is a good network citizen and works to ensure that the all circuits created by it are load-balanced across the volunteer driven Tor network.”