p2psp team mailing list archive

["L.G.Casado" <leo@xxxxxx>]

Dear Ilshat,
Yes, more than one trusted peer seems not to be interesting for current
coded attacks.
Nice results. 
Best,
Leo 
El lun, 24-08-2015 a las 02:57 +0600, Ilshat Shakirov escribió:
> Hello!,
> 
> Here are some final results of testing STrPe&STrPe-DS mechanisms.
> 
> STrPe-DS | Persistent attack: https://docs.google.com/spreadsheets/d/
> 1iSNQwanXT10XravpkfPz706ASdeIv3NvUOF0QqMU3rg/edit#gid=0
> STrPe-DS | On-off attack: https://docs.google.com/spreadsheets/d/1Acr
> hbcFvd_iRISeDa26ObRiApPHpV4-BqPoRipiKRcc/edit#gid=0
> Network usage (by rounds): https://docs.google.com/spreadsheets/d/1Lh
> ypThplzYVpiNWfnuLH73H-ZagznKO2BYzjCk1dXdE/edit?usp=sharing
> 
> The really interesting result is network usage sheet. The both
> mechanisms have very low overhead (no more than 10%, service
> messages, like list of bad peers, chunk_check message and so on)
> costs very low traffic.
> Tests was performed in the team with 10 peers (9 well-intended peers
> and one trusted peer).
> 
> About STrPe-DS:
> Also, in case of persistent attack and on-off attack mal. peers was
> discovered very fast. Also, number of trusted peers in the team
> doesnt affect on this speed (at all). So, in on-off attack I
> performed tests only with 1 TP.
> Because of this speed, mal. peers don't have time to do much harmful
> effect on the team, it can be seen on buffer_filling graphs.
> 
> Currently, Im preparing last blogpost.
> 
> Thanks!
> 
> 2015-08-18 18:36 GMT+06:00 Ilshat Shakirov <im.shakirov@xxxxxxxxx>:
> > Hello!,
> >  
> > > They are nice results.
> > Thanks! 
> >  
> > > What 40% on-off attack means? 
> > In 40% of cases peer sends poisoned chunk instead of correct chunk.
> > 
> > 
> > 2015-08-18 17:34 GMT+05:00 L.G.Casado <leo@xxxxxx>:
> > > Dear Ilshat,
> > > 
> > > They are nice results.
> > > What 40% on-off attack means? 
> > > 
> > > 
> > > Best,
> > > 
> > > Leo
> > > 
> > > El mar, 18-08-2015 a las 17:24 +0500, Ilshat Shakirov escribió:
> > > > Hello!,
> > > > 
> > > > Here is small status update.
> > > > I've implemented new types of attack for malicious peers:
> > > > -persistent attack
> > > > -on-off attack
> > > > -selective attack
> > > > -bad-mouth attacj (for strpe-ds only)
> > > > 
> > > > Also, I've added new option --checkall for STrPe trusted peers.
> > > > If this option is enablde, then TP sends every received chunk
> > > > to splitter to check.
> > > > 
> > > > Here is some tests I performed for STrPe mechanism:
> > > > Persistent attack (with checkall option) : https://docs.google.
> > > > com/spreadsheets/d/1iNva1mvO9NETj8fJ9oZpy1VhAUYxJi4K7gUojqzSEqI
> > > > /edit
> > > > On-off attack (40%) : https://docs.google.com/spreadsheets/d/1-
> > > > sLkrjdNQHx-jXxWeVYz4pmnd6qgC1D3MuVnbhQ4lYE/edit?usp=sharing
> > > > 
> > > > For each configuration Ive performed 5 experiments, on last tab
> > > > the result table is presented.
> > > > 
> > > > I've made next observations (for STrPe):
> > > > - there is need to increase splitter's buffer, since it have to
> > > > check chunks which can be deleted from its buffer. I've
> > > > performed tests with --buffer_size 1024 (256 by default). I
> > > > think that buffer should smth like 4 * team_size.
> > > > - with check all option number of TP doesnt affect speed of
> > > > expulsion mal. peers (in case of persistent attack). Every mal.
> > > > peer is excluding for 1 splitter round in average.
> > > > - in on-off attack number of TP affects on speed of excluding
> > > > peers. So, more TPs - more chances to send posioned chunks to
> > > > TP.
> > > > - there is very small affect on buffer correctness for all the
> > > > team. Average for the team is between 0.95 and 1.
> > > > 
> > > > Also, here is my testing plan : https://docs.google.com/documen
> > > > t/d/13oSUgkRrmUh8nM3mMe5FEmwBlSfrxs0NXkei0JVubBo/edit?usp=shari
> > > > ng
> > > > 
> > > > Currently, Im performing tests for STrPe-DS mechanism
> > > > (according to my test plan).
> > > > 
> > > > Thanks.
> > > > 
> > > > 2015-08-14 2:03 GMT+05:00 Ilshat Shakirov <
> > > > im.shakirov@xxxxxxxxx>:
> > > > > Hello!,
> > > > > 
> > > > > Here is two raw data sets with result data from experiments
> > > > > with STrPe and STrPe-DS:
> > > > > 
> > > > > STrPe: https://docs.google.com/spreadsheets/d/13xzEwQKbB58p0K
> > > > > 8VyQjvez2L-QABP_ouelbqmWMSE7w/edit#gid=1026220953
> > > > > STrPe-DS: https://docs.google.com/spreadsheets/d/1YZnLaWrjAJR
> > > > > gXZ2LQrHhgewOnzL1Fm073ix6dULmwpc/edit#gid=1531244678
> > > > > 
> > > > > As you can see in STrPe number of TP affects on speed of
> > > > > expulsion mal. peers. It happens because TP selects next
> > > > > chunk to check randomly from its stream of chunks. Resp. if
> > > > > we have more TP then it will take less number of rounds to
> > > > > expel all TP.
> > > > > You can check it in code here: https://github.com/P2PSP/p2psp
> > > > > /blob/cis/src/trusted_peer.py#L55
> > > > > 
> > > > > Also, you can see that in STrPe-DS if we have more mal.
> > > > > peers, we have more rounds to expel all mal. peers. It
> > > > > happens because including new mal. peers take 0.5 - 1 round,
> > > > > and resp. we have more rounds to include all mal. peers to
> > > > > the team. In the simple persistent attack mal. peers
> > > > > excluding almost at the same time they sended poisoned chunk
> > > > > to TP.
> > > > > 
> > > > > > Why a TP does not check every chunk?
> > > > > > In a persistent attack, peers will be detected directly.
> > > > > > 
> > > > >  
> > > > > Because it can reduce the performance of TP and the system (I
> > > > > think) 
> > > > > 
> > > > > > Again, for persisten attack this is true, but not for the
> > > > > > more sophisticated ones.
> > > > > What kinds of attack should I perform?
> > > > > 
> > > > > Also, I think I know how to compromise Third Trusted Party
> > > > > (and resp. perform selective attack) for only log(n) time.
> > > > > Attacker should perform attack on the half of the team. If
> > > > > mal. peer was excluded, then in given half exists TP. Then
> > > > > this half divide to new 2 halfs and so on. So, we can find
> > > > > all the TPs in O(log2(n)) time.
> > > > > 
> > > > > Thanks!
> > > > > 
> > > > > 
> > > > > 2015-08-12 15:43 GMT+05:00 L.G.Casado <leo@xxxxxx>:
> > > > > > Hello,
> > > > > > 
> > > > > > 
> > > > > > El mié, 12-08-2015 a las 15:27 +0500, Ilshat Shakirov
> > > > > > escribió:
> > > > > > > Hello,
> > > > > > > 
> > > > > > > > N-1, is set because there is one Trusted peer, does it?
> > > > > > > Yes, because trusted peer doesnt check itself.
> > > > > > >  
> > > > > > > > How is set X, random check yes/no?  
> > > > > > > > 
> > > > > > > I think yes. In the first impl of STrPe trusted peers
> > > > > > > checked every 255 received chunk.
> > > > > > > 
> > > > > > Why a TP does not check every chunk?
> > > > > > In a persistent attack, peers will be detected directly.
> > > > > > 
> > > > > > The random check could be seen as malicious peer performing
> > > > > >  a kind of selective attack.
> > > > > > 
> > > > > > > About current progress:
> > > > > > > I've found a small bug in the initialization of big teams
> > > > > > > (i.e. 100 peers) with enabled STrPe-DS. In 2-3% of cases
> > > > > > > peer hangs up and do nothing.
> > > > > > Then, they should be expeled soon.
> > > > > > 
> > > > > > > Also, Ive prepared a raw data from STrPe experiments (Ive
> > > > > > > performed experiments with 100 peers, 1-2-4-8 trusted,
> > > > > > > and 10-25 malicious). And since trusted peers in STrPe
> > > > > > > checks chunks randomly from all the peers in the team, it
> > > > > > > can take long time to expel all the malicious peers. It
> > > > > > > happens because TP selects chunk to check from all
> > > > > > > stream, although it should select chunks from each peer.
> > > > > > I think to check randomly has no sense if trusted peer is
> > > > > > in system without resources limitations, which should be
> > > > > > the case.
> > > > > > 
> > > > > > > If we implement this, then Juan will be right and number
> > > > > > > of TPs in the team won't have impact on mal. peer
> > > > > > > expulsion. Now, if we have more TP, we have more chances,
> > > > > > > that TP will check chunk from mal. peers and will exclude
> > > > > > > it.
> > > > > > Yes, checking them all, just on TP is enough for persistent
> > > > > > attack, but it is not the case for other attacks.
> > > > > > 
> > > > > > > Also, STrPe-DS don't have such problem, because I've
> > > > > > > implemented next logic:Every S seconds splitter selects
> > > > > > > new peer from all the team and TP from trusted peers and
> > > > > > > do 2 requests to gather complains from the team. 
> > > > > > > So, mal. peers will be excluded almost in the same time
> > > > > > > they ve sended poisoned chunks to TP.
> > > > > > > 
> > > > > > Again, for persisten attack this is true, but not for the
> > > > > > more sophisticated ones.
> > > > > > > Thanks!
> > > > > > > 
> > > > > > Best,
> > > > > > 
> > > > > > Leo
> > > > > > 
> > > > > > > 2015-08-12 15:08 GMT+05:00 L.G.Casado <leo@xxxxxx>:
> > > > > > > > Dear Ilshat,
> > > > > > > > 
> > > > > > > > El mié, 12-08-2015 a las 12:04 +0200, L.G.Casado
> > > > > > > > escribió:
> > > > > > > > > BC = 1 - M / (N - 1 + 1) = 1 - M / N,
> > > > > > > > Sorry, the formula was fine:
> > > > > > > > 
> > > > > > > > (N-M)/N= 1-M/N
> > > > > > > > 
> > > > > > > > Please, answer the other questions.
> > > > > > > > 
> > > > > > > > Thanks,
> > > > > > > > 
> > > > > > > > Leo
> > > > > > > > 
> > > > > 
> >