4/7/2005

The Sybil Attack

This paper presents a proof.  The proof states that distributed systems are inherently 
exploitable.   This paper is interesting because it presents its argument concisely with a 
series of lemmas.  The key exploitation method provided by the paper is the use of 
multiple identities by a malicious node.  The paper argues that this exploitation technique 
is impossible to counter in a practical system.

The weakness of the paper is the fact that it is entirely focused on one type of 
exploitation: the use of multiple identities.  The reader can not help but suspect that the 
claim the paper makes is sweeping, but it is build on a very narrow foundation.  For 
example, assuming a practical solution is invented to counter the one type of fraud this 
paper focuses on, then this papers entire sweeping assertion would be incorrect.