I didn't know anything about this until today. I have a feeling that it must be a sort of DDoS attack. Someone has attacked both Skype servers and the P2P network. Skype's architecture relies on a set of super-nodes like Gnutella to route calls and even authentications . Of course it's unclear how Skype decide which clients to be super-nodes, but i speculates that they amounts upto 70% of the network.
Well, taking down these number of nodes are not easy, but the connectivity of the network *maybe* heavy-tailed, and if a determined attacker can work out those highly-connected nodes and take them down, the entire networks would go to pieces. David Barrett wrote: > Reading the Skype blog post, it doesn't sound like the problem was due to > lack of central resources, but rather some catastrophic bug in the P2P > network itself -- like it was unable to reform the DHT (or whatever) in the > wake of a massive churn event. > > I mean, it shouldn't take *2 days* to log in 9 million users, and unless > this was coupled with servers actually suffering hardware malfunction (of > which there's no indication), I can't see any reason why it'd take that long > to simply deal with a big backlog of authentication requests. > > Does anyone know much about the Skype P2P/DHT/network algorithm, and can > they hypothesize what sort of event could cause it to take so long to get > back into operation? > > Also, was Skype 100% down for 2 days followed by it coming 100% back up > (indicative of a central server problem), or was it suffering from varying > levels of failure throughout that took a couple days to clear up (suggesting > P2P network problems)? > > -david > >> -----Original Message----- >> From: [EMAIL PROTECTED] [mailto:p2p-hackers- >> [EMAIL PROTECTED] On Behalf Of Alen Peacock >> Sent: Monday, August 20, 2007 1:39 PM >> To: theory and practice of decentralized computer networks >> Subject: Re: [p2p-hackers] what really happened to Skype? >> >> Absolutely true that Skype hasn't given us enough details to figure >> out exactly what happened or why, but that doesn't prevent the looser >> cannons among us from taking a shot: >> http://flud.org/blog/2007/08/20/p2ps-skype-induced-blackeye-or-why- >> diversity-is-good/ >> >> Alen >> >> >> On 8/20/07, zooko <[EMAIL PROTECTED]> wrote: >>> Folks: >>> >>> This is a fascinating case study, but we don't yet have enough >>> information to really learn from it! >>> >>> http://heartbeat.skype.com/2007/08/what_happened_on_august_16.html >> _______________________________________________ >> p2p-hackers mailing list >> [email protected] >> http://lists.zooko.com/mailman/listinfo/p2p-hackers > > _______________________________________________ > p2p-hackers mailing list > [email protected] > http://lists.zooko.com/mailman/listinfo/p2p-hackers _______________________________________________ p2p-hackers mailing list [email protected] http://lists.zooko.com/mailman/listinfo/p2p-hackers
