[bittorrent] "removed" peers in PEX

BeCe boski_cinek at o2.pl
Wed May 27 09:37:50 EDT 2009

I'm designing survivable BT-based network (for my master thesis). The 
goal is to create DDoS resistant file distribution network, that 
supports updates (with additional data verification - GPG by default). 
Because working without tracker is a criticial requirement (it's most 
probable target for DDoS) for my network I want to use Peer Exchange 
extension as part of my design. I believe I already understand how PEX 
works, but what I don't know is how is the content of "removed" peers 
list created. I mean, how peer knows that he should remove specific peer 
from list, and more important why this is relevant to receiver of such 
list? How should he react after getting removed peers list? Is he 
supposed to remove those peers from his list without checking? And if 
yes, isn't that possible threat (first peer could potentially make 
second to remove all, or most of his neighbours leaving him disconnected 
from swarm. Of course 1st would need to know 2nd peers list first)?
Greets, BeCe

More information about the BitTorrent mailing list