[ANN] TagCoin - Multi Token Wallet and Trading Platform

[ahmed_bodi]

we really need a dev to check. i'll see if i can get hold of one

First couple rounds of beers/shots are on me.

-Fuse

im muslim i dont drink , but everyone else can have my share

A halal feast is in order then.  Baraka Allah.

-Fuse

Halal feast it is, Jazakallah

[vesperwillow]

Update I was working on reviewing code, but have been pulled away because of work. If I can come back to it I will.

[altcoinspool]

Have you guys had a previously-confirmed block (or more than one) turn orphan hundreds or thousands of confirmations later? That's always fun.

Did I mention http://altcoinspool.com/lost-tag-coins.txt ? That's just how many confirmed blocks we lost.

The sad part is, we sent about 6k to an exchange before deciding to bring them back and hold onto them. Sending the TAG to the exchange worked, and bringing them back worked. They were all orphaned the next morning.

[altcoinspool]

Halal feast it is, Jazakallah

Suphaan Allah,

May Allah be pleased with all of you for your efforts.

BaraqAllahu fiqom.

[ahmed_bodi]

Halal feast it is, Jazakallah

Suphaan Allah,

May Allah be pleased with all of you for your efforts.

BaraqAllahu fiqom.

Inshallah! Nice to see fellow muslims around here

[ny2cafuse]

Any updates on the code investigation?  I'm interested to see what's found out.

-Fuse

[vesperwillow]

Any updates on the code investigation?  I'm interested to see what's found out.

-Fuse

From the few moments I had to glance it over, the tag difficulty/target math was almost exactly the same as in that example link. There was a function in a different order but the math appeared to be the same overall. I didn't have time to actually break all of the math out and try it. There didn't appear to be anything in place to prevent negative targetspacing, but this was just a cursory glance. Maybe I'll get time to look at it today.

I almost want to just take the easy way out and set my private pool's time ahead and see what happens lol.

[vesperwillow]

Here's the TAG source code I snipped out which relates to the discussion. I don't  know if it's important, but this appears to only deal with POS. The POW difficulty code is on the other side of the ELSE block, and isn't in use because we're past block 12000. Perhaps there's other code elsewhere, I'll look later.

static const int64 nMaxClockDrift = 2 * 60 * 60; // two hours

unsigned int nStakeMinAge = 60 * 60 * 24 * 30; // minimum age for coin age (2592000s = 30d)
unsigned int nStakeMaxAge = 60 * 60 * 24 * 90; // stake age of full weight (7776000s = 90d)
unsigned int nStakeTargetSpacing = 4 * 60; // 4-minute block spacing (240s)

static const int64 nTargetTimespan = 2 * 60 * 60;  //7200s 2 hrs
static const int64 nTargetSpacingProofOfWork = 4 * 60;   //240s 4 min
static const int64 nTargetSpacingWorkMax = 3 * nTargetSpacingProofOfWork; //720s 12 min

int64 nTargetSpacing = fProofOfStake? nStakeTargetSpacing : min(nTargetSpacingWorkMax, (int64) nStakeTargetSpacing * (1 + pindexLast->nHeight - pindexPrev->nHeight));

//New difficulty algorithm
if (nHeight >= 12000)
{
    CBigNum bnTargetLimit = !fProofOfStake ? bnProofOfWorkLimit : bnProofOfStakeLimit;

    if (pindexLast == NULL)
        return bnTargetLimit.GetCompact(); // genesis block

    const CBlockIndex* pindexPrev = GetLastBlockIndex(pindexLast, fProofOfStake);
    if (pindexPrev->pprev == NULL)
        return bnTargetLimit.GetCompact(); // first block
    const CBlockIndex* pindexPrevPrev = GetLastBlockIndex(pindexPrev->pprev, fProofOfStake);
    if (pindexPrevPrev->pprev == NULL)
        return bnTargetLimit.GetCompact(); // second block

    int64 nActualSpacing = pindexPrev->GetBlockTime() - pindexPrevPrev->GetBlockTime();
   

    // ppcoin: target change every block
    // ppcoin: retarget with exponential moving toward target spacing
    CBigNum bnNew;
    bnNew.SetCompact(pindexPrev->nBits);
    int64 nTargetSpacing = fProofOfStake? nStakeTargetSpacing : min(nTargetSpacingWorkMax, (int64) nStakeTargetSpacing * (1 + pindexLast->nHeight - pindexPrev->nHeight));
    int64 nInterval = nTargetTimespan / nTargetSpacing;
    bnNew *= ((nInterval - 1) * nTargetSpacing + nActualSpacing + nActualSpacing);
    bnNew /= ((nInterval + 1) * nTargetSpacing);

    if (bnNew > bnTargetLimit)
        bnNew = bnTargetLimit;

    return bnNew.GetCompact();
 }
else    //Old difficulty algorithm, prior to block 12000
 {
        if (!fProofOfStake && nHeight<390)                //initial funds for distribution and promotion, keep diff low
                return bnProofOfWorkLimit.GetCompact();
        
        if (!fProofOfStake && nHeight==390)                //starting difficulty of 0.5 for PoW
                return bnInitialProofOfWorkDifficulty.GetCompact();
        
    CBigNum bnTargetLimit = !fProofOfStake ? bnProofOfWorkLimit : bnProofOfStakeLimit;

    if (pindexLast == NULL)
        return bnTargetLimit.GetCompact(); // genesis block

    const CBlockIndex* pindexPrev = GetLastBlockIndex(pindexLast, fProofOfStake);
    if (pindexPrev->pprev == NULL)
        return bnTargetLimit.GetCompact(); // first block
    const CBlockIndex* pindexPrevPrev = GetLastBlockIndex(pindexPrev->pprev, fProofOfStake);
    if (pindexPrevPrev->pprev == NULL)
        return bnTargetLimit.GetCompact(); // second block
        
        CBigNum bnNew;
    bnNew.SetCompact(pindexPrev->nBits);
        
        if (fProofOfStake)                        //PoS difficulty algo. recalc every block.
    {
                int64 nActualSpacing = pindexPrev->GetBlockTime() - pindexPrevPrev->GetBlockTime();
                int64 nTargetSpacing = nStakeTargetSpacing;
                int64 nInterval = nTargetTimespan / nTargetSpacing;
                bnNew *= ((nInterval - 1) * nTargetSpacing + nActualSpacing + nActualSpacing);
                bnNew /= ((nInterval + 1) * nTargetSpacing);
        }
        
        if (!fProofOfStake)                        //PoW difficulty algo. recalc every interval.
   {
        int64 nInterval = nTargetTimespan / nTargetSpacingProofOfWork;
        
    // Only change once per interval
    if ((nHeight) % nInterval != 0)
                return pindexLast->nBits;
                
        // This fixes an issue where a 51% attack can change difficulty at will.
    // Go back the full period unless it's the first retarget after genesis. Code courtesy of Art Forz
    int blockstogoback = nInterval-1;
    if ((nHeight) != nInterval)
        blockstogoback = nInterval;

    // Go back by what we want to be the last intervals worth of blocks
    const CBlockIndex* pindexFirst = pindexLast;
    for (int i = 0; pindexFirst && i < blockstogoback; i++)
        pindexFirst = pindexFirst->pprev;
    assert(pindexFirst);
        
        // Limit adjustment step
    int64 nActualTimespan = pindexLast->GetBlockTime() - pindexFirst->GetBlockTime();
    printf(" nActualTimespan = %"PRI64d" before bounds\n", nActualTimespan);
        
    int64 nActualTimespanMax = nTargetTimespan * 1.25;
    int64 nActualTimespanMin = nTargetTimespan * 0.75;
        
        if (nActualTimespan < nActualTimespanMin)
        nActualTimespan = nActualTimespanMin;
    if (nActualTimespan > nActualTimespanMax)
        nActualTimespan = nActualTimespanMax;
                
    bnNew *= nActualTimespan;
    bnNew /= nTargetTimespan;
   }

    if (bnNew > bnTargetLimit)
        bnNew = bnTargetLimit;

    return bnNew.GetCompact();
 }

And here's what appears to be part of the trust section of the protocol which we all waited for Feb 2nd for:

   /* Old protocol */
if (GetBlockTime() < FIX_SWITCH_TIME)
 {   
    if (IsProofOfStake())
    {
        // Return trust score as usual
        return (CBigNum(1)<<256) / (bnTarget+1);
    }
    else
    {
        // Calculate work amount for block
        CBigNum bnPoWTrust = (bnProofOfWorkLimit / (bnTarget+1));
        return bnPoWTrust > 1 ? bnPoWTrust : 1;
    }
 }
 
    /* New protocol */
 
    // Calculate work amount for block
    CBigNum nPoWTrust = (CBigNum(nPoWBase) / (bnTarget+1));

    // Set nPowTrust to 1 if we are checking PoS block or PoW difficulty is too low
    nPoWTrust = (IsProofOfStake() || nPoWTrust < 1) ? 1 : nPoWTrust;

    const CBlockIndex* currentIndex = pprev;

    if(IsProofOfStake())
    {
        CBigNum bnNewTrust = (CBigNum(1)<<256) / (bnTarget+1);

        // Return 1/3 of score if parent block is not the PoW block
        if (!pprev->IsProofOfWork())
            return (bnNewTrust / 3);

        int nPoWCount = 0;

        // Check last 12 blocks type
        while (pprev->nHeight - currentIndex->nHeight < 12)
        {
            if (currentIndex->IsProofOfWork())
                nPoWCount++;
            currentIndex = currentIndex->pprev;
        }

        // Return 1/3 of score if less than 5 PoW blocks found
        if (nPoWCount < 5)
            return (bnNewTrust / 3);

        return bnNewTrust;
    }
    else
    {
        CBigNum bnLastBlockTrust = CBigNum(pprev->bnChainTrust - pprev->pprev->bnChainTrust);

        // Return nPoWTrust + 3/4 of previous block score parent block is not PoS
        if (!pprev->IsProofOfStake())
            return nPoWTrust + (3 * bnLastBlockTrust / 4);

        int nPoSCount = 0;

        // Check last 12 blocks type
        while (pprev->nHeight - currentIndex->nHeight < 12)
        {
            if (currentIndex->IsProofOfStake())
                nPoSCount++;
            currentIndex = currentIndex->pprev;
        }

        // Return nPoWTrust + 3/4 of previous block score if less than 4 PoS blocks found
        if (nPoSCount < 4)
            return nPoWTrust + (3 * bnLastBlockTrust / 4);

        bnTarget.SetCompact(pprev->nBits);

        if (bnTarget <= 0)
            return 0;

        CBigNum bnNewTrust = (CBigNum(1)<<256) / (bnTarget+1);

        // Return nPoWTrust + full trust score for previous block nBits
        return nPoWTrust + bnNewTrust;
    }   
   
}

[Dabs]

Okay, what's the English version? hehe. LOL, sorry. But I'm asking for everyone else's sake, I'm a some times coder so I can attempt to figure it out.

[trcwhale]

Okay, what's the English version? hehe. LOL, sorry. But I'm asking for everyone else's sake, I'm a some times coder so I can attempt to figure it out.

I was about to say this as well.

Can someone let me know what's going on? Is network still having issues. To disclose I have about 2000 TAG. Dont know what to do.

[vesperwillow]

I haven't had time to look at the code, but I posted the relevant sniippets in case someone can digest the math from the code. I won't be available for the next few days, for anything other than quick message responses. Otherwise I would've looked into it..

There's still orphans occuring, not as bad as before, but it's odd how some pools seem to get waves and others don't. We're trying to look into possibilities why. I've been focused on POTcoin lately, and even with significant hash flux, it's never been an issue on that coin.

[ny2cafuse]

There's still orphans occuring, not as bad as before, but it's odd how some pools seem to get waves and others don't. We're trying to look into possibilities why.

I've got an idea of why some pools aren't getting hit as hard with orphans lol.

Hey, China... how's the weather over there?

-Fuse

[ahmed_bodi]

There's still orphans occuring, not as bad as before, but it's odd how some pools seem to get waves and others don't. We're trying to look into possibilities why.

I've got an idea of why some pools aren't getting hit as hard with orphans lol.

Hey, China... how's the weather over there?

-Fuse

whats the idea? pm?

[tagbond]

AS far as I am concerned the code and the coin are fine...it seems to be fairly stable other than occasional orphans popping up on mining pools - I thought it may have something to do with not everyone being on the latest version. As for anything else nefarious, that would require a hefty chunk of the hashpower to mess with the chain, more than anyone has right now. But if anyone has any concrete info as to why the occasional orphans appear, let us know.

As for the value dropping, well.. BTC has dropped quite a bit and so have most coins. Untill we have a more solid footing with merchants, we are still linked to Bitcoin, as are most coins.

TAG is still moving around ok for transactions, and we are still moving ahead with developments with merchants here in the philippines as well as online via our own developments. I will let you know soon about some interesting projects coming out over the next few weeks..

[vesperwillow]

AS far as I am concerned the code and the coin are fine...it seems to be fairly stable other than occasional orphans popping up on mining pools - I thought it may have something to do with not everyone being on the latest version. As for anything else nefarious, that would require a hefty chunk of the hashpower to mess with the chain, more than anyone has right now. But if anyone has any concrete info as to why the occasional orphans appear, let us know.

As for the value dropping, well.. BTC has dropped quite a bit and so have most coins. Untill we have a more solid footing with merchants, we are still linked to Bitcoin, as are most coins.

TAG is still moving around ok for transactions, and we are still moving ahead with developments with merchants here in the philippines as well as online via our own developments. I will let you know soon about some interesting projects coming out over the next few weeks..

Mark, there are some attacks which have been carried out in recent weeks which do not rely on hashpower. They simply rely on bandwidth. You could hold 90% of the hashpower, but if you can't talk you're dead in the water.

I've also begun noticing an emerging pattern across several coin networks, with TAG being one of the hardest hit: Previously confirmed blocks going orphans. Not just hours later, not just thousands of confirms later, but we're talking days later. Completely out of nowhere, with no network hashrate change.

So far the one thing they all have in common is the peculiarity of the situation. I haven't examined what each coin is based off of (to see if it's a code issue), but even if it isn't a code issue, it could in fact be network manipulation. Ghosts in the machine exist for a reason.

It's understandable to have a block show up as orphan, even within a few minutes of being found, but as a coin developer/supporter, how can you explain to us blocks which are goin orphan so far after being confirmed?

And one other question, why can't you have your primary developer spend 15 minutes to examine the code quoted above, to determine if the negative retarget bug may be affecting TAG? Wouldn't 15 minutes go a long way?

[ahmed_bodi]

^ very true vesperwillow

[crypto777]

    TAGCOIN - ON POSITION 55 - TRADING ACTIVITY ON CRYPTSY.COM

   
    Here Cryptsy Live Statistics - http://live.myip.ms

[tagbond]

@vesperwillow - we wrote that code, and so far we don't see anything wrong with it. Can you?..As for orphans being created from old confirmed blocks, we are at a loss as to explain this. Can you say what other coins this is happening to?

maxpower just created a mac version of the 1.0.5 wallet:
https://www.dropbox.com/s/gyyra84qm9zcdmu/TagCoin-Qt-1.0.5-Mac.zip

Just trying to push that up to the server from here in Korea, but not going up just yet...can use the link above till then..will work on the ubuntu version when I am back in the office on Tuesday.

[ahmed_bodi]

@vesperwillow - we wrote that code, and so far we don't see anything wrong with it. Can you?..As for orphans being created from old confirmed blocks, we are at a loss as to explain this. Can you say what other coins this is happening to?

maxpower just created a mac version of the 1.0.5 wallet:
https://www.dropbox.com/s/gyyra84qm9zcdmu/TagCoin-Qt-1.0.5-Mac.zip

Just trying to push that up to the server from here in Korea, but not going up just yet...can use the link above till then..will work on the ubuntu version when I am back in the office on Tuesday.

the main ones that its happened to is orbitcoin, i believe android tokens, starcoin, colossuscoin and possibly others may have had this issue

[tagbond]

I think that what is happening is due to old versions of the client still in use, some back to 1.0.2. Using getpeerinfo you can check that for yourself. Not a lot I can do about it except remind people to use the latest version. so as far as I am concerned the code is stable, the chain is stable and I can move forward with developments to use TAG in earnest.