Changes between Version 41 and Version 42 of thesis


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Timestamp:
Apr 26, 2011 3:38:19 PM (9 years ago)
Author:
zzz
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  • thesis

    v41 v42  
    202202< NOTE: Our DDoS involved 40 peers hitting a single peer.[[BR]][[BR]]
    203203
     204**> Right. What I meant to say in a) above, (and I elaborated the details in a conversation with you) was a limit on the number of tunnels that can be built in a specific time frame with a single peer as the previous or next hop. These limits are fairly low, such that it will take a large number of peers. This number may be more or less than 40 depending on the capacity of the victim. You were (I think) building one-hop tunnels in the attack. The new restrictions can be evaded by building longer tunnels, with a variety of other peers in intermediate hops. So the new restrictions add some marginal cost but are not a complete solution.
     205
    204206    b) Penalize peers more due to tunnel rejections. This did not change the time constants of the capacity formulas, just changed (a + r) to (a + 2r) in the denominator of the formula in section A.1. However it may have had the effect of reacting faster to a DOS attack. This change was not made in reaction to the attack, but was previously planned and is part of a strategy to spread the traffic across more peers in the network and adjust the forumla in response to network conditions that have changed markedly in the past two years.
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