> On 3 Jun 2015, at 02:07 , teor <[email protected]> wrote:
> 
> 
>> Date: Mon, 18 May 2015 15:48:50 -0800
>> From: OnioNS Dev <[email protected]>
>> 
>> ...
>> 
>> I introduce several data structures, but the most important one is the 
>> Pagechain, a distributed structure of linked Pages. Pages contain Records, 
>> Records contain .tor -> onion associations. Anyone who is familiar with 
>> blockchains will recognize the behavior and application of this structure 
>> immediately. However, here the head of the Pagechain is not managed by 
>> miners, but rather by a short-lived subset of Tor nodes called a Quorum. 
>> They receive Records and merge them into the Pagechain. At the moment I've 
>> decided to use 127 Quorum members and rotate them every week. They are 
>> randomly selected, but the process is deterministic; I am using the 
>> cached-certs + cached-microdesc-consensus documents, which everyone has, to 
>> seed a PRNG that then derives the Quorum.
> 
> What's to stop a sybil attack where the malicious relays try to occupy likely 
> site(s) for the next Quorum?
> 
> Is the consensus unpredictable enough to thwart this attack?
> Even during quiet times? (Does Tor have quiet times?)
> 
> Can we ensure the Quorum servers have to be long-lived and high-capacity (for 
> example, guards) to make it harder to spin up servers and immediately be 
> added to the Quorum?
> I'm not convinced the Stable flag is hard enough to get.
> 
> Of course, there's a trade-off where making the set of Quorum Candidates too 
> small makes the Quorum easier to predict, too.

Some day, I will learn to read the whole paper before opening my mouth.

I apologise - I withdraw my questions in the face of thousands of bits of 
entropy per hour, and a comprehensive security analysis.

> By the way, in your ACM paper 5.4.2 you switch from Charlie to Alice, but I 
> think they're meant to be the same Quorum Candidate.

In an earlier section, "Alice" is a Tor client. This makes this section make 
sense.


teor

teor2345 at gmail dot com
pgp 0xABFED1AC
https://gist.github.com/teor2345/d033b8ce0a99adbc89c5

teor at blah dot im
OTR D5BE4EC2 255D7585 F3874930 DB130265 7C9EBBC7

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