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Topic: Adi Shamir's paper on bitcoin - page 2. (Read 31426 times)

donator
Activity: 2772
Merit: 1019
October 31, 2012, 02:03:11 PM
In case someone missed it, I posted a link to the old version in the previous post.

thanks. I tried to make another diff, but I'm having a hard time (line breaks have to be removed, my pdf reader's copy to clipboard function screws up on many chars, hyphenation marks need to be removed, etc). It'd be awesome to have the sources (tex or whatever they are).

Right now it's too much effort for me unless someone has a great idea on how to get clean(er) text from the pdfs.

Why doesn't Dorit Ron pop in here and suck all knowledge from us and use our resources? Is there some formal reason like having to write the thesis on her own?
Probably due to low signal to noise ratio on this forum. I agree that they should have consulted with local and global Bitcoin experts at a much earlier point. (Speaking of which we're talking about me coming to visit for a meeting of faculty interested in Bitcoin and/or the paper).

Cool!

By the way Adi and probably also Dorit are reading these threads.

Hello! *waves*
hero member
Activity: 504
Merit: 504
PGP OTC WOT: EB7FCE3D
October 27, 2012, 04:17:35 PM

As pointed out by Davout, the paper assumes shared wallets like mt gox are ONE owner of a lot of addresses. This logic is flawed.


Also - it seems a bit strange to count the 2Million+ sub 0.01 balance wallets as the poor end of some sort of wealth pyramid.
Many of these are surely people who just tried it out, e.g by getting some from a freebie site. They may or may not even have kept that wallet, let alone become engaged as an active Bitcoin user.

Some of those might be miners, collecting a lot of little bits of change.


or service operators collecting fees from transactions
legendary
Activity: 1120
Merit: 1152
October 27, 2012, 03:02:33 PM
In case someone missed it, I posted a link to the old version in the previous post.

(1) We shouldn't forget it's not really Adi Shamir's paper, but his grad student Dorit Ron's paper, who according to her linked-in page is working on a masters degree.
Link? According to http://www.wisdom.weizmann.ac.il/~dron/ she's been writing papers for 28 years (and in case there is another Dorit Ron at WIS, the emails match).

Ah, look like I'm wrong then. The linked-in page was found by someone I know who has a pro-account, so they might have found the wrong person. I edited my post to make this clear.

Why doesn't Dorit Ron pop in here and suck all knowledge from us and use our resources? Is there some formal reason like having to write the thesis on her own?
Probably due to low signal to noise ratio on this forum. I agree that they should have consulted with local and global Bitcoin experts at a much earlier point. (Speaking of which we're talking about me coming to visit for a meeting of faculty interested in Bitcoin and/or the paper).

That's great news!

Finding info on the forums is definitely difficult, and in addition Dorit seems to be a mathematician rather than a programmer, which would explain why she used what to us is a convoluted way of generating the results. Note how she acknowledged help from someone else in parsing the block chain itself.
donator
Activity: 2058
Merit: 1054
October 27, 2012, 02:37:16 PM
In case someone missed it, I posted a link to the old version in the previous post.

(1) We shouldn't forget it's not really Adi Shamir's paper, but his grad student Dorit Ron's paper, who according to her linked-in page is working on a masters degree.
Link? According to http://www.wisdom.weizmann.ac.il/~dron/ she's been writing papers for 28 years (and in case there is another Dorit Ron at WIS, the emails match).

She would have done essentially all the work with Adi only supervising.
Even if that was true, "supervising" doesn't mean not having a clue what the research is about.

Quite possibly prior to publishing the paper Adi didn't actually know much about Bitcoin.
I don't know if he knew much about Bitcoin, but he's interested in cryptocurrencies and has said "of course I've heard about Bitcoin" as early as a year ago.


Why doesn't Dorit Ron pop in here and suck all knowledge from us and use our resources? Is there some formal reason like having to write the thesis on her own?
Probably due to low signal to noise ratio on this forum. I agree that they should have consulted with local and global Bitcoin experts at a much earlier point. (Speaking of which we're talking about me coming to visit for a meeting of faculty interested in Bitcoin and/or the paper).

By the way Adi and probably also Dorit are reading these threads.
legendary
Activity: 3920
Merit: 2349
Eadem mutata resurgo
October 27, 2012, 02:24:43 PM
It seems to me that best incentive for doing this kind of work is to figure out how much information is currently available from the block-chain, so that better privacy enhancing techniques can be developed to thwart further analysis. Rinse and repeat, so to speak.
donator
Activity: 2772
Merit: 1019
October 27, 2012, 02:23:49 PM
Why doesn't Dorit Ron pop in here and suck all knowledge from us and use our resources? Is there some formal reason like having to write the thesis on her own?
legendary
Activity: 1120
Merit: 1152
October 27, 2012, 02:18:39 PM
You know, it'd be worth it for someone to try to replicate the whole paper with our own toolchain, such as znort's blockchain parser, and publish our own findings. If I had the free time I'd look into doing so myself.

If there was an expectation of getting meaningful results I guess the incentive to do this might be higher.

Just "showing Adi how it's done right" is not worth the effort in my mind. I don't think the way he did it invalidates the results.

Still: if you find the time: go for it! Maybe you can find even more interesting results.

If I'd do something like this, I'd use bitcoin-abe and sql-queries.

I'm thinking do this first of all just to check that their(1) statistics were correct in the first place. For all we know some problems exist at the core of these results, and it'd also be useful to get more details on, for example, the claim of that 70,000BTC "laundering" transaction. It's one of the things that bothers me about the paper actually: they should have published what transactions they were talking about in many of the examples. (modulo privacy considerations where they have identified someone)

Once you can reproduce those results, then you can work on more exciting concepts. Maybe those exciting measurements will only happen after time has been spent struggling? Don't forget that another perfectly valid result is that people in the Bitcoin community who really understand the system have spent a lot of time thinking about the problem, and can't find any way to get statistics out of the system.

I agree that incentive is a problem. Myself I already have school, work, and a timestamping project to juggle. More generally replication papers in science are never sexy.


(1) We shouldn't forget it's not really Adi Shamir's paper, but his grad student Dorit Ron's paper, who according to her linked-in page is working on a masters degree. She would have done essentially all the work with Adi only supervising. Quite possibly prior to publishing the paper Adi didn't actually know much about Bitcoin. However now that it's raised a lot of controversy I'm not surprised that Adi seems to be the one handling emails; it is his reputation on the line after all and he's the one with experience handling controversial results. <- wrong, see https://bitcointalksearch.org/topic/m.1301988
donator
Activity: 2772
Merit: 1019
October 27, 2012, 01:14:43 PM
You know, it'd be worth it for someone to try to replicate the whole paper with our own toolchain, such as znort's blockchain parser, and publish our own findings. If I had the free time I'd look into doing so myself.

If there was an expectation of getting meaningful results I guess the incentive to do this might be higher.

Just "showing Adi how it's done right" is not worth the effort in my mind. I don't think the way he did it invalidates the results.

Still: if you find the time: go for it! Maybe you can find even more interesting results.

If I'd do something like this, I'd use bitcoin-abe and sql-queries.
legendary
Activity: 1120
Merit: 1152
October 27, 2012, 01:06:24 PM
can someone post a diff or have the old version? I'd like to see what got changed.

https://s3.amazonaws.com/retep/2012BitcoinFinalNonAnonymous.pdf
This isn't the old version, it's something between the old and new. As such, there are many changes not appearing in molecular's diff. I'll try to look for the original version.

Thanks, I'd appreciate a copy for my archives as well. There's probably going to be at least one more additional revision, if only because Adi offered to acknowledge me by name as well. I also pointed out in my last email that the definition for inactive addresses, which appears to be on a per-address rather than per-transaction basis, has the problem where the people who seem to be sending dust spam to random addresses can incorrectly cause both older, pre-Mt.Gox addresses to be appear to be active after that date and then subsequently inactive and considered to be savings.

You know, it'd be worth it for someone to try to replicate the whole paper with our own toolchain, such as znort's blockchain parser, and publish our own findings. If I had the free time I'd look into doing so myself.
donator
Activity: 2772
Merit: 1019
October 27, 2012, 12:25:27 PM
can someone post a diff or have the old version? I'd like to see what got changed.

https://s3.amazonaws.com/retep/2012BitcoinFinalNonAnonymous.pdf
This isn't the old version, it's something between the old and new. As such, there are many changes not appearing in molecular's diff. I'll try to look for the original version.

damnit! I figures as much when I arrived at the Acknowledgements. Finished regardless.

Offering to do it again.
donator
Activity: 2058
Merit: 1054
October 27, 2012, 11:02:42 AM
can someone post a diff or have the old version? I'd like to see what got changed.

https://s3.amazonaws.com/retep/2012BitcoinFinalNonAnonymous.pdf
This isn't the old version, it's something between the old and new. As such, there are many changes not appearing in molecular's diff. I'll try to look for the original version.

Update: Adi has informed me that all revisions are available at http://eprint.iacr.org/cgi-bin/versions.pl?entry=2012/584. In particular the first version is at http://eprint.iacr.org/cgi-bin/getfile.pl?entry=2012/584&version=20121016:132906&file=584.pdf.

Note that the intermediate one retep uploaded isn't there, it was mailed to some of the people who communicated with the authors.
donator
Activity: 2772
Merit: 1019
October 27, 2012, 03:28:18 AM
can someone post a diff or have the old version? I'd like to see what got changed.

https://s3.amazonaws.com/retep/2012BitcoinFinalNonAnonymous.pdf

Thanks, retep, for the link. I made a diff of the textual changes. Changes marked in bold:

-------------------------------------------------------------------------------

In many places:

Quote from: previous revision
bitcoin

Quote from: current revision
Bitcoin

Page 3:

Quote from: previous revision
Payments are made inAnd in the Acknowledgements: bitcoins (BTC's), which are digital coins issued and transferred by the bitcoin network. Nodes broadcast transactions to this network, which records them in publicly available web pages, called block chains, after validating them with a proof-of-work system.

Quote from: current revision
Payments are made in bitcoins (BTC's), which are digital coins issued and transferred by the Bitcoin network. The data of all these transactions, after being validated with a proof-of-work system, is collected into what is called the block chain.

Page 12:

Quote from: previous revision
A common prominent practice of bitcoin users is to create chains of consecutive transactions as can be seen in Fig. 7: An initial amount of 50,000 BTC's is rapidly transferred from one address to another leaving out some small amounts. In this example 350 such transactions are carried out within the fi rst two days during which the initial amount of 50,000 BTC's is reduced to 34,000 BTC's. In the next three weeks an additional 100 transactions follow and the amount is further reduced to merely 15,000 BTC's. A similar chain of length 120, with initial amount of 500,000 BTC's which decreases to 340,000 BTC's at the end of the chain, is shown in Fig. 1. Note that some of the transactions in this chain are carried out by Mt.Gox. Additional such chains can be found in Fig. 2, Fig. 3, Fig. 4 and Fig. 5, with lengths of 3, 15, 23, 26, 80 and 88 transactions.

Quote from: current revision
A common prominent practice of Bitcoin users is to create chains of consecutive transactions. Some of these chains can be explained by the change mechanism in which small payments are accompanied by the creation of a new address, into which the user transfers the di erence. Such chains can be found in Fig. 2, Fig. 4, Fig. 5 and Fig. 7, with lengths of 3, 15, 26, 80, 88 and 350 transactions. However, the behavior seen in Fig. 3 deviates significantly from this pattern, since the same amount of 5,000 bitcoins is repeatedly split o ff the main sum and put into accounts which have no additional transactions associated with them.


And in the Acknowledgements:

Quote from: previous revision
Finally, we would like to thank all the members of the bitcoin community who sent us excellent comments criticisms and suggestions.

Quote from: current revision
Finally, we would like to thank all the members of the Bitcoin community, and in particular Meni Rosenfeld and Stefan Richter, who sent us excellent comments, criticisms and suggestions.
legendary
Activity: 1120
Merit: 1152
October 27, 2012, 12:22:07 AM
can someone post a diff or have the old version? I'd like to see what got changed.

https://s3.amazonaws.com/retep/2012BitcoinFinalNonAnonymous.pdf <- EDIT: taken down, I accidentally uploaded the revision circulated to authors. Meni found a link to all revisions published at http://eprint.iacr.org/cgi-bin/versions.pl?entry=2012/584
donator
Activity: 2772
Merit: 1019
October 26, 2012, 04:31:56 PM
can someone post a diff or have the old version? I'd like to see what got changed.
hero member
Activity: 756
Merit: 501
There is more to Bitcoin than bitcoins.
October 26, 2012, 08:50:48 AM
Now this is peer review as it should be.  Smiley
p2p Cheesy
hero member
Activity: 952
Merit: 1009
October 26, 2012, 05:32:21 AM
Now this is peer review as it should be.  Smiley
donator
Activity: 2058
Merit: 1054
October 26, 2012, 03:30:07 AM
Some changes have been made to the paper based on the community's feedback. The revised version is available at the same URL, http://eprint.iacr.org/2012/584.pdf.
donator
Activity: 2772
Merit: 1019
October 21, 2012, 04:24:49 AM
hmm, either Shamir has gotten "old and ignorant" (like Stallman?) or someone else did this "study" and he just put the name.

Perhaps it isn't a good idea to show too much understanding of Bitcoin when there are legions trying to out Satoshi, and you are a reknown cryptographer in the list of top-10 suspects. Endorsing a poorly researched whitepaper pretty much disqualifies Dr Shamir as a potential Satoshi in the public eye. What better way to divert attention?
I can't think of any other rational reason why a high-flying cryptographer as A. Shamir would associate his name with such an unchallenging and unscientific study.

I am not telling that A. Shamir is Satoshi.
Only that this looks like an attempt, for understandable reasons, to dissociate himself from Satoshi.

That somehow reminds of Paco Ahlgren's strange (but again totally understandable) badly acted denial when he went under scrutiny after writing a (perhaps a bit too much) enthusiastic article about Bitcoin.


Interview with Adi Shamir:

Interviewer: "Mr. Shamir, please explain to our viewers, what is the bitcoin blockchain"

Adi Shamir: "The bitcoin blockchain is a list of html pages *twitch* that are connected by hyperlinks *flinch* -- *eyes widen* AAAAAH FUCK IT, I CAN'T DO THIS ANY LONGER!!! THERE, I'LL ADMIT IT TO END THIS CRUEL TORTURE:

I  A M  S A T O S H I !

And the blockchain is this BIEST that listens to us and will eat the creature from jekyll island for breakfast quite soon! Muahahahaaaaaahaaaaaaaaa!"

hero member
Activity: 770
Merit: 500
October 21, 2012, 02:25:28 AM
#99
The biggest flaw on the paper is the webscraping of blockchain data.
Right there they destroyed any assurance they could have of working with validated data.
How do they know they were fed the correct data by blockchain.info or blockexplorer.com?
The only way to be sure you have the correct blockchain data is to let your bitcoin client download it from the network and verify it. You may also download a blockchain snapshot, but you still need to let the client verify it to be sure what you have is real data and not some decoy.

The paper shall be renamed "Quantitative Analysis of a Full Blockexplorer.com Screen Scraping"
hero member
Activity: 756
Merit: 501
There is more to Bitcoin than bitcoins.
October 21, 2012, 12:38:33 AM
#98
hmm, either Shamir has gotten "old and ignorant" (like Stallman?) or someone else did this "study" and he just put the name.

Perhaps it isn't a good idea to show too much understanding of Bitcoin when there are legions trying to out Satoshi, and you are a reknown cryptographer in the list of top-10 suspects. Endorsing a poorly researched whitepaper pretty much disqualifies Dr Shamir as a potential Satoshi in the public eye. What better way to divert attention?
I can't think of any other rational reason why a high-flying cryptographer as A. Shamir would associate his name with such an unchallenging and unscientific study.

I am not telling that A. Shamir is Satoshi.
Only that this looks like an attempt, for understandable reasons, to dissociate himself from Satoshi.

That somehow reminds of Paco Ahlgren's strange (but again totally understandable) badly acted denial when he went under scrutiny after writing a (perhaps a bit too much) enthusiastic article about Bitcoin.


You think too highly of scientific publications... Cheesy  What fraction of today's papers showcase reliable, in-depth, non-biased, honest results anyway? 
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