The attack doesn't seem that realistic though, as it relies on someone going long on BTS and then attacking the BTS price.

1) a buy a bunch of BTS, then a bunch of bitCNY. In a properly functioning market, I paid a premium for bitCNY because 1 bitCNY is supposed to be > 1 CNY.
2) I request a forced settlement (losing the premium I paid).
3) I wait 23 hours and sell all the BTS I bought (which incurs a loss as I drive down the market)
4) my forced settlement goes through, and I get a lot of BTS because of my attack. But those BTS are now worth less than what I paid for them in order to get the CNY in the first place.

In the end: I paid a premium to buy CNY, which I lost. I sold a lot of BTS for less money than I paid for them. I force settled my CNY for more BTS than the CNY was originally worth (as long as I can overcome the premium I paid). Now I have BTS, which are not worth very much since I drove down the price and I overpaid for CNY in the first place.

If one has a lot of bts at the start, she can get more bts by this attack, although the "total value" of her bts may not increase in the end.

If I want to make an account that is controlled by multiple other accounts how do I change the authority using the CLI?

If I want to propose a transaction from this account and have all other account owners ratify the transaction how do you do that from the CLI?

Can any of this be done from the GUI?

For the first one, try here: https://bitshares.openledger.info/#/account/clout/permissions

Quote from: jakub on November 29, 2015, 01:37:02 pm

Quote from: svk on November 28, 2015, 01:30:36 pm

I still think most people don't understand how margin calls work in BTS 2.0, so in a bid to clarify things I've created a Google Doc that explains the mechanics of margin calls as per my current understanding.

I'd appreciate some input on the correctness, and if something's wrong I'll update it. You can add comments directly in the doc.

@alt @tonyk @Xeldal @bytemaster

https://docs.google.com/document/d/1h9E6N9VECh48NKRQGFoPQsSwfZXT4p_TD3LT3CqeTYk/edit?usp=sharing

Nice write-up, @svk
I've put my comments in the document.

I fully agree with your suggestions but they might not be relevant any more. AFAIK bytemaster has already fixed the margin call mechanism, it just awaits tests and a hard-fork to be implemented.

Thanks.

What have they been "fixed" to though?

https://github.com/cryptonomex/graphene/issues/436

As already stated the witnesses need a new script to fix the issue.
The script will needs a partial refactoring on how to calculate the feed for CNY related markets.
Xeroc needs time to make this happen.

My feed prices are always a bit higher than others.
Sources of the difference are:
1. I don't pull btc prices from bitcoinaverage but from btc/cny pair of yunbi/btc38.
2. I ignored other btc pairs of btc38 and yunbi

Wish this helps.

Quote from: onceuponatime on November 27, 2015, 05:43:36 pm

Quote from: oldmine on November 27, 2015, 05:33:39 pm

Quote from: Chronos on November 27, 2015, 05:29:44 pm

I don't like implementing a hard fork to change fee allocation to go to a specific account. It's not very decentralized. Perhaps a UIA-based solution is better.

Yep it sounds shit.

@Chronos  If you could articulate how a UIA would escape the regulatory concern of issuing a "security" it would be helpful.

@oldmine   I am having trouble understanding what your contribution is adding to the search for solutions as to how to fund new features..

why a UIA would be considered a "security"? It can simply be a UIA like all the ones people create  with no real value like "goodidea" opensesame" ,"brownies" etc..with no strings attached like AGS was in the past. People decide to buy it because they believe it "may" have some value like earning fees from stealth transfers..I don't see any legal binding in all that or any kind of "security"..

1) BM issues the UIA with a fixed amount and price so total market cap is $45k
2)  people buy into that via bitusd and bts
3) BM uses converts the bitusd and bts in usd
4) Owners of the UIA "may" receive the fees from the stealth transfers for life
5) Problem solved right?

Everything is based on trust.No legal binding. No "security"

Legal issues.

http://cryptofresh.com/b/1287679

Tx 1f4a34b5ed0d4ac3ec7ee9f463a6d92ca8557d0f@1287679
abit issued 1,000,000 THUMBSUP to sharebits
block 1,287,679


Will it reach my account @sharebits? I can't see it in the panel.
I thought the memo I entered is correct.
Or the deposit only works with transfer?

Quote from: bitcrab on November 27, 2015, 04:40:34 am

are you sure the settle price is always the settlement price(feed price)?
if yes, then when one user settle, who is his counterparty?

It should take the highest bids first, down to the feed, and then the least collateralized short.

A side note, if there are bids higher than feed price already, why bitcny holders would use settle instead of sell?
If there are active settle orders already, why place bids higher than feed price?

By the way the fee for placing a settle order is 200BTS.

I would advice add a parameter for settle price rate: settle price = feed price * rate
the rate's range can adjust from 95% to 105%, mostly it should more than 100%

and need another logic to protect shorters, if a shorter's colla rate is more than 200%,  no one can settle from him.

No need to set another parameter, just feed the settlement_price to what it should be, it's designed to should not be equal to (weighted) average exchange price.

bts's price is 0.021CNY/BTS at BTC38
but most witness give a feed price at 0.02 CNY/BTS, so the settle price is 0.02

The reason is the price feed script calculates price of bts/cny not only from btc38/yunbi, but also includes some weight by [average price of bts/btc on poloniex/bitfinex] * [average price of btc/usd on external exchanges(bitstamp and so)] * [usd/cny price from yahoo]. When prices of BTC on USD exchanges are lower than which on CNY exchanges, the bts/cny price feed will be lower than the price on btc38.

what will happen?
people sell BTS at BTC38 at price 0.021, get fiat CNY, then sell fiat CNY to transwiser, get bitCNY, then settle at the wallet, buy back BTS at price 0.02
who gets hurt? the shorters again! why we always hurt the shorters? they provide liquility, but we hurt them again and again

In this case Transwiser should charge more fees while selling bitCNY.
And Transwiser should consider it's collateral level seriously to avoid being forced settled.

d) chinese exchanges without trading fees should be considered as well when providing a CNY price feed

btc38 also have trading fees, why not use

I believe that most of witnesses already included btc38 and yunbi in the price feeds.
The problem is that BTC price on CNY exchanges and USD exchanges are usually different, and a big volume of BTS is trading with BTC, so the price of BTS fed into the system is usually different to the price in CNY (on btc38 and yunbi).