>> 1) The cost of IPs vs. bandwidth is definitely a function of market offers. >> Your $500/Gbps/month seems quite expensive compared to what can be found on >> OVH (which is hosting a large number of relays): they ask ~3 euros/IP/month, >> including unlimited 100 Mbps traffic. If we assume that wgg = 2/3 and a >> water level at 10Mbps, this means that, if you want to have 1Gbps of guard >> bandwidth, >> - the current Tor mechanisms would cost you 3 * 10 * 3/2 = 45 euros/month >> - the waterfilling mechanism would cost you 3 * 100 = 300 euros/month > > The question of what the cheapest attack is can indeed be estimated by > looking at market prices for the required resources. Your cost estimate of > 3.72 USD/Gbps/month for bandwidth seems off by two orders of magnitude.
I see that I misread your cost calculation, and that you estimated $37.20/Gbps/month instead of $3.72/Gbps/month. This still seems low by an order of magnitude. Thus, my argument stands: waterfilling would appear to decrease the cost to an adversary of getting guard probability compared to Tor’s current weighting scheme. Best, Aaron _______________________________________________ tor-dev mailing list tor-dev@lists.torproject.org https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev
