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Author Topic: [ANN][YAC] YACoin ongoing development  (Read 331935 times)
sairon
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January 02, 2014, 06:15:31 PM
 #1601

How come Peercoin doesn't have these problems? Or do they?
I have lost tons of YACoin from BTER-- they are scamming a lot of people. So I won't be in a position to offer bounties for a while. What would be the best type of bounty?  More pools with different features? A javascript mining program/pool like bitminter?  I cringe at the idea of centralized checkpointing or reduced POS awards.
Peercoin is using the centralized checkpointing approach as far as I can tell.

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January 02, 2014, 06:24:07 PM
 #1602

Peercoin is using the centralized checkpointing approach as far as I can tell.

It is, as well as NVC. If we can find a way to both avert this issue, AND not implement centralized checkpointing (which I also don't agree with), it would be a great way
to distinguish YAC even more.  Of course Sunny King is pretty fucking brilliant and probably pondered this forever, so that may still be the only way  Undecided

I'm trying to stay out of this debate (another way to avoid centralized "checkpointing"  Wink ) but we really need to do something soon.  I think a Feb 1st hard fork date, as mentioned before would be sufficient though.   
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January 02, 2014, 06:28:51 PM
 #1603

(eg. you deposit YAC to exchange, wait until the exchange credits you the deposited balance, block gets "magically" orphaned - and you now have both your YACs AND credit at an exchange - that's why Cryptsy has been disabling YAC trading lately).

Why would an exchange give you credit for freshly minted coins, unless they deliberatedly wanted the risk.

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January 02, 2014, 06:30:58 PM
 #1604

Peercoin is using the centralized checkpointing approach as far as I can tell.

It is, as well as NVC. If we can find a way to both avert this issue, AND not implement centralized checkpointing (which I also don't agree with), it would be a great way
to distinguish YAC even more.  Of course Sunny King is pretty fucking brilliant and probably pondered this forever, so that may still be the only way  Undecided

I'm trying to stay out of this debate (another way to avoid centralized "checkpointing"  Wink ) but we really need to do something soon.  I think a Feb 1st hard fork date, as mentioned before would be sufficient though.    

Has this idea been done?  Built-in POW-POS-POW-POS staggered blocks?  What implications does it have other than fix the POW orphan problem (ie unintended consequences)?

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sairon
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January 02, 2014, 06:41:20 PM
 #1605

(eg. you deposit YAC to exchange, wait until the exchange credits you the deposited balance, block gets "magically" orphaned - and you now have both your YACs AND credit at an exchange - that's why Cryptsy has been disabling YAC trading lately).

Why would an exchange give you credit for freshly minted coins, unless they deliberatedly wanted the risk.

NOT freshly minted... -.-"
You just CAN'T spend freshly minted coins until there's 520 more blocks above the one you minted.
I was referring to TRANSACTIONS. The block CONTAINING your transaction gets orphaned. It DOES NOT need to be YOUR block.

And YAC had some chain reorgs deeper than 50 blocks (50 confirmations of transaction!) as the consequence of all this badly-designed PoS bullshit.


Built-in POW-POS-POW-POS staggered blocks?  What implications does it have other than fix the POW orphan problem (ie unintended consequences)?
It's not just pow-pos-pow-pos. It can just as well be pow-pos-pow-pow-pow-pow-pos. There's no limit on how much consecutive PoW blocks are there in the chain - just that 2 PoS blocks can't be directly linked.

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January 02, 2014, 06:49:06 PM
 #1606

Would it be possible to implement automatic calculation of how many PoS blocks can be allowed one after another based on N factor?
This is my idea and let's say for example that we get a new fork on February 1st. Column "Blockchain example" shows what could be allowed ( Nfactor-13 consecutive PoS blocks )

▉  PoW
◔   PoS

NfactorDate timeConsecutive PoS blks allowedBlockchain exampleNMemoryTimestamp
14We are here◔◔◔◔◔◔◔◔◔◔◔327684 MB1384768416
14Sun 1 Feb 2014 00:00:001▉◔▉▉▉◔
15Sat 31 May 2014 14:13:522▉◔◔▉◔◔▉▉▉◔655368 MB1401545632
16Fri 05 Sep 2014 16:24:003▉◔◔◔▉◔◔▉▉◔◔◔13107216 MB1409934240
17Tue 23 Jun 2015 22:54:244▉◔◔◔◔▉◔◔◔◔▉26214432 MB1435100064
18Sat 16 Jul 2016 07:34:565▉◔◔◔◔◔▉◔◔◔◔◔▉52428864 MB1468654496
19Tue 08 Aug 2017 16:15:286 or perhaps release restrictions?1048576128 MB1502208928
20Fri 16 Oct 2020 18:17:04?2097152256 MB1602872224



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bitdwarf
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January 02, 2014, 06:53:08 PM
 #1607

You just CAN'T spend freshly minted coins until there's 520 more blocks above the one you minted.

Yes. But exchanges and businesses could still wait until there's 1040, 2080 or 10400 before they take your fresh coins if they don't want the risk of transaction reversal.

We could make the standard wallet freeze coins for that much longer, so they can't be put in outgoing transactions. If someone receives "fresh" coins, they know the other person is going all the way to use a hacked wallet which immediately flags it as fishy.

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sairon
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January 02, 2014, 06:55:00 PM
 #1608

Would it be possible to implement automatic calculation of how many PoS blocks can be allowed one after another based on N factor?
This is my idea and let's say for example that we get a new fork on February 1st. Column "Blockchain example" shows what could be allowed ( Nfactor-13 consecutive PoS blocks )

▉  PoW
◔   PoS

NfactorDate timeConsecutive PoS blks allowedBlockchain exampleNMemoryTimestamp
14We are here◔◔◔◔◔◔◔◔◔◔◔327684 MB1384768416
14Sun 1 Feb 2014 00:00:001▉◔▉▉▉◔
15Sat 31 May 2014 14:13:522▉◔◔▉◔◔▉▉▉◔655368 MB1401545632
16Fri 05 Sep 2014 16:24:003▉◔◔◔▉◔◔▉▉◔◔◔13107216 MB1409934240
17Tue 23 Jun 2015 22:54:244▉◔◔◔◔▉◔◔◔◔▉26214432 MB1435100064
18Sat 16 Jul 2016 07:34:565▉◔◔◔◔◔▉◔◔◔◔◔▉52428864 MB1468654496
19Tue 08 Aug 2017 16:15:286 or perhaps release restrictions?1048576128 MB1502208928
20Fri 16 Oct 2020 18:17:04?2097152256 MB1602872224




By allowing N consecutive PoS blocks, you're essentially giving ANYONE with some YACs available the ability to orphan the latest N-1 blocks. With N == 1 you can't orphan anything. (All that assuming PoS block trust is equal to PoW block trust.)

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sairon
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January 02, 2014, 06:59:18 PM
 #1609

You just CAN'T spend freshly minted coins until there's 520 more blocks above the one you minted.

Yes. But exchanges and businesses could still wait until there's 1040, 2080 or 10400 before they take your fresh coins if they don't want the risk of transaction reversal.

We could make the standard wallet freeze coins for that much longer, so they can't be put in outgoing transactions. If someone receives "fresh" coins, they know the other person is going all the way to use a hacked wallet which immediately flags it as fishy.

Well, this hinders the usability of YAC, then... YAC would be absolutely unusable the way you propose.

With the workaround I proposed, you can be certain that only someone with control of 51% or more of the network hashrate can orphan blocks - and that it actually costs him something to attempt that kind of thing.

The way it is now even a McDonald's worker screaming for higher minimum wage can orphan as many YAC blocks as he likes.

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January 02, 2014, 07:03:43 PM
 #1610

Also, the gain from orphaning PoS is ZERO.
It feels like this could be used so game the system.

The new rules make it possible to destroy PoS since they favour PoW so extreme over PoS. Maby there isn't even a profitable exploid for them, but we surely couldn't rule that out. If there is one we couldn't fix without a hardfork and that's something we couldn't agree on.

On the other hand a lot of important groups could egoistically benefit from a non working PoS system. Miners would love to mine all blocks and rich people would like to exclude most other people from PoS. It doesn't matter that 99.99% get screwd in the current banking system as long as those 0.01% can make the rules and profit from them.


We need to find a way that favours a combination of PoW/PoS over a system with just one of those. The "no 2 PoS-blocks touching"-rule prevents PoW to extinct, but how can we protect PoS*?

The current system also protects both, but unfortuneatly it doesn't work. If we want it to be fixed with something that doesn't risk PoS or PoW. (Even if that is CentralCheckpoints, but I really hate that)


*)In a useful form. A fixed fee, f.e 50YAC/PoSbock wouldn't affect me at all, but most others couldn't PoS anymore and so make it useless. I'd even benefit from everyone having to pay such fee.

Sorry that it took me 20replies to write this. I will comment on those once I've read them.
Never took me so long to formulate an idea


Sign a message and get some YAC: https://bitcointalk.org/index.php?topic=300152.0
sairon
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January 02, 2014, 07:09:19 PM
 #1611

The new rules make it possible to destroy PoS since they favour PoW so extreme over PoS.

No, it does not favor PoW over PoS - both have the exact same value.

Orphaning a single PoS block with PoW is VERY HARD with the new rules (right now even more so).
Orphaning a single PoW block with PoS is IMPOSSIBLE with the new rules (right now you can orphan a SHITLOAD of PoW blocks effortlessly).

EDIT: to clarify - you can create an alternative fork with PoS block under the new rules (assuming that the second to last block was not PoS) - but that's not an issue. To actually orphan the legitimate block you'd have to also PoW mine at least one block after your PoS block.

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January 02, 2014, 07:26:58 PM
 #1612

Has this idea been done?  Built-in POW-POS-POW-POS staggered blocks?  What implications does it have other than fix the POW orphan problem (ie unintended consequences)?
I belive that (if profitable) miners/groups interrested could rape (think of it as a hack) the protocoll and make PoS useless.
You can't ban PoW-PoW-PoW since we don't have that many PoS, we're only talking about banning POS-POS


If significant (<50%) of miners could agree f.e. on not accepting a small PoS block and only working on top of big PoS and PoW blocks. Just because the protocoll says that you should always build on top of the longest chain doesn't mean it can force you to always do.


How miners could profitable ignore small PoS blocks:

1)New unofficial rule: Don't build on small PoS blocks or better ask for a fixedPoS-fee (no fork or official announcement)
2)A new small PoS apears, but miners rather continue their work on a block where a lot of work has been done already.

No PoS-block could be mined on top of the small PoS so they don't matter at all. Only PoW matters and the honest network would have to be stronger than the unethical network that has already done a lot of work. Beeing unethical gives more rewards since rewards on PoW>>>>>PoS.

Big wallests will always be able to protect there PoS-blocks with a fixed fee and most others won't be able to pay such fee.

--> PoS useless.

The argument ("but then they will have to fight against honest PoS and PoW") doesn't work either. (Pooling PoS possible)

EDIT:red stuff

Sign a message and get some YAC: https://bitcointalk.org/index.php?topic=300152.0
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January 02, 2014, 07:34:50 PM
 #1613

Having read more articles and publications on POS and attacks, and listening to input here, I really can't offer a better solution than no consecutive POS blocks.  

Knowing POS exists as a wey to secure the blockchain with less electricity waste may not be as critical to YACoin as it is to other coins.  With a higher N, the power consumption on my cards is lower (comparing YAC to LTC or any other N=9 Scrypt coin).  This may drop even further i the future.  If disallowing consecutive POS blocks now keeps YAC from imploding, I say we have to do it.  This may be a case of kicking the can down the road, but the only other solution we've seen implemented is centralization of the blockchain.

One question I still have is : what is to prevent a user from forcing the generation of a POS block (which is just a flag when starting the wallet now, correct?), jumping offline before the generation is complete and coming back on 6 hours later.  Does it attach to the end of the blockchain? or does it insert where the blockchain was when the block was generated (not submitted), potentially orphaning 360 blocks?  

If anyone has any good references on the subject, I'd love to read them.  I've read
https://en.bitcoin.it/wiki/Proof_of_Stake
http://bitcoinmagazine.com/6528/
http://www.peercointalk.org/index.php?topic=936.0
http://www.peercointalk.org/index.php?topic=809.0
http://www.peercointalk.org/index.php?topic=979.0

YACMiner: https://github.com/Thirtybird/YACMiner  N-Factor information : https://docs.google.com/spreadsheet/ccc?key=0Aj3vcsuY-JFNdC1ITWJrSG9VeWp6QXppbVgxcm0tbGc&usp=drive_web#gid=0
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sairon
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January 02, 2014, 07:38:40 PM
 #1614

One question I still have is : what is to prevent a user from forcing the generation of a POS block (which is just a flag when starting the wallet now, correct?), jumping offline before the generation is complete and coming back on 6 hours later.  Does it attach to the end of the blockchain? or does it insert where the blockchain was when the block was generated (not submitted), potentially orphaning 360 blocks?  

He can generate a PoS block wherever in the chain he likes, however with trust reduced to 1 it's useless to do so. And the "no consecutive PoS" rule prevents him from doing any damage even if he has millions of PoS-eligible inputs.

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January 02, 2014, 07:43:49 PM
 #1615

The whole point of PoS was to add security and inflation. Favoring PoW over PoS or vice-versa isn't benefiting one rich group over another.  If anything, PoS favors the 'rich'. I think there is a problem with bitcoin and litecoin when inflation through PoW slows and eventually stops completely. I think a great coin would allow a modest amount of inflation (2% or more) through PoW indefinitely (by percentage, not fixed number of coins).

I'm still wondering what disallowing consecutive PoS blocks will do aside from fixing the PoW orphan issue.  Does that mean coins could be 'staked' for much longer? How long? There seems to be a lot of gamemanship with PoS minting, and I'm not sure that fix would change that aspect... it would just change the rules of the game.  

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January 02, 2014, 07:53:29 PM
 #1616

The new rules make it possible to destroy PoS since they favour PoW so extreme over PoS.
No, it does not favor PoW over PoS - both have the exact same value.
I'm not talking about individual blocks, I'm talking about the whole PoS system vs the whole PoW system.
It favours it since PoW can ophran a PoS but it's not possible the other way round.
That's something we want, but also something that brings new problems.

PoW miners will never be able to remove the whole PoS function and every block, but they could make the whole PoS system useless in order to maximize profits. I belive the rules you proposed are they only way besides CentralCheckpoints to solve the current doublespend problem.

They do come with some enourmous problems that we have to fix befor we implement them, later isn't possible. I don't think we can change your rules, but we have to add something to them to save POS. Doubling rewards for a PoW block after a PoS would strengten PoS but also increase inflation dramatically.

Then we would also have to change the chaintrust on PoS blocks so that always the biggest PoS candidate wins.
This will be a complex problem if we don't want to screw up.

Sign a message and get some YAC: https://bitcointalk.org/index.php?topic=300152.0
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January 02, 2014, 07:55:28 PM
 #1617

Favoring PoW over PoS or vice-versa isn't benefiting one rich group over another.
Only when PoS is fair and the new rules could be abused so that only rich adresses (>10kYAC) can PoS while most other (poor) people can't)

Sign a message and get some YAC: https://bitcointalk.org/index.php?topic=300152.0
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January 02, 2014, 07:58:30 PM
 #1618

PoW miners will never be able to remove the whole PoS function and every block, but they could make the whole PoS system useless in order to maximize profits. I belive the rules you proposed are they only way besides CentralCheckpoints to solve the current doublespend problem.

PoW miners certainly won't maximize their profits by orphaning PoS. On the contrary - their mining revenue would be much lower if they decided to attempt orphaning PoS.

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January 02, 2014, 08:14:20 PM
 #1619

One question I still have is : what is to prevent a user from forcing the generation of a POS block (which is just a flag when starting the wallet now, correct?), jumping offline before the generation is complete and coming back on 6 hours later.  Does it attach to the end of the blockchain? or does it insert where the blockchain was when the block was generated (not submitted), potentially orphaning 360 blocks?  

He can generate a PoS block wherever in the chain he likes, however with trust reduced to 1 it's useless to do so. And the "no consecutive PoS" rule prevents him from doing any damage even if he has millions of PoS-eligible inputs.

So, it appears that the genesis for the hash on a POS block is based on the coin age of the input.  If POS isn't successful (due to the most recent block being POS), then the coin age is not destroyed, and can be attempted later, which can be as soon as a minute (in an ideal model) as a miner finds a POW block to sit on top of the minter's POS block.

I just wasn't certain if the whole orphaning was being caused by the POS blocks having to be inserted into the blockchain at the point it was generated as opposed to when the minter was connected to the network.

Is cementing an option, or would that be really bad with our current distribution of hashpower (mostly centralized)?  https://en.bitcoin.it/wiki/Proof_of_Stake#Cementing

YACMiner: https://github.com/Thirtybird/YACMiner  N-Factor information : https://docs.google.com/spreadsheet/ccc?key=0Aj3vcsuY-JFNdC1ITWJrSG9VeWp6QXppbVgxcm0tbGc&usp=drive_web#gid=0
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sairon
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January 02, 2014, 08:19:38 PM
 #1620

One question I still have is : what is to prevent a user from forcing the generation of a POS block (which is just a flag when starting the wallet now, correct?), jumping offline before the generation is complete and coming back on 6 hours later.  Does it attach to the end of the blockchain? or does it insert where the blockchain was when the block was generated (not submitted), potentially orphaning 360 blocks?  

He can generate a PoS block wherever in the chain he likes, however with trust reduced to 1 it's useless to do so. And the "no consecutive PoS" rule prevents him from doing any damage even if he has millions of PoS-eligible inputs.

So, it appears that the genesis for the hash on a POS block is based on the coin age of the input.  If POS isn't successful (due to the most recent block being POS), then the coin age is not destroyed, and can be attempted later, which can be as soon as a minute (in an ideal model) as a miner finds a POW block to sit on top of the minter's POS block.

I just wasn't certain if the whole orphaning was being caused by the POS blocks having to be inserted into the blockchain at the point it was generated as opposed to when the minter was connected to the network.

Is cementing an option, or would that be really bad with our current distribution of hashpower (mostly centralized)?  https://en.bitcoin.it/wiki/Proof_of_Stake#Cementing

IMO cementing is a bad idea as it requires us to trust PoS (which we don't as of now).
Also there could be some race-conditions and other nasty issues that could easily result in network fragmentation.

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