Some people were saying it's the same person who put up the 3 million NXT sell wall. Just a mass liquidation of all their crypto apparently. No specific BBR related reason from what I can tell.

'zmark' isn't a new algo but just the name that they chose for their pfennig fork. I think right now they are testing DGW on it, no major modifications yet as far as I know. But the plan is to try to come up with an algo that is able to reduce supply as well. Vertcoin recently annouced that they've mannaged to develop such an algo, but as far as I know it's not released yet. So maybe we'll be able to try testing that one out on the zmark testchain at some point soon.

Here's some recent chat from #pfennig on slack. Anyone who wants an invite feel free to PM me.

00:39] markpfennig: Is there a summary of any alernative algo's discussed or found or implemented which control the supply whilst varying diff?

[00:43] amarha: i don't think they're at that point yet

[00:43] amarha: although i could be wrong

[01:37] dbkeys: Basically, KGW was the first one, but it has a time warp exploit. Someone with more than 50% of the hashing power can play games with time and give themselves lots of easy blocks.

[01:38] dbkeys: I was strongly advised by "The Altcoin Guy" to use Dark Gravity Wave, as it is simpler and has proven more resistant to attack.

[01:38] dbkeys: DigiShield, used in a number of coins (originally DigiByte I believe) and notably DOGE, has also been advocated. I know little about how it works.

[01:39] dbkeys: Leathans and I own idea is that we have to first understand what these algorithms are doing before we choose one, or adopt aspects of it into our own.

[01:40] dbkeys: Basically, we have a situation where the difficulty easily adjusts upward but once hash power leaves the network, is very slow (in real time terms) to come back to a reasonable value.

[01:41] leathan: amarha: correct we sorta skipped over that for some reason when we get a better udnerstanding of them i doubt we will go with any existing one like dbkeys said (or if we do it will be most likly a modified version)

[01:42] dbkeys: I'm inclined to think about how the honest peers in the network can keep closer track of real time, by requiring some type of time-consensus that guarantees a minimum block production rate. Emdje has pointed out that the probability that more than a 4 or 5 two-minutes intervals going by without the production of a block quickly goes down down as being attributable to a Poission random process and rapidly, with great certainty, becomes indicative of reduced network hash power.

[01:43] dbkeys: Clearly, after more than some threshold number of block-less time intervals (perhaps as low as 4 or 5, ie, (8 or 10 minutes in BTM block-time) the difficulty should begin to be ratcheted down.

[01:46] dbkeys: An analysis of peaks and valleys of hashrate looking back several week (perhaps even to the beginning of the coin's history) and an analysis of the average hourly coin emission rate could be used by an algorithm to not only set  a reasonable difficulty factor, but also a block-reward that does not create more coins than hashrate, as a measure of demand, would seem to warrant.

[01:47] leathan: We should talk to that math chairman guy dbkeys :S (edited)

[01:49] dbkeys: I also like the notion that if the hash rate goes down significantly from recent historical peaks, not only should the difficulty go down somewhat, and the block reward reduced, but (within a certain limit) the block-time-interval target itself could be made longer than the nominal 2 minutes, to allow for the fact that there is reduced demand for the coin, _AND_ still provide a meaningful amount of proof-of-work by the remaining honest hash power.

[01:50] dbkeys: This would be an "elastic time-interval-target" that could range from the nominal 2 minutes betweeen blocks (when hashrate is at a peak) to perhaps ranging as hig as10x longer or 100x loner ( 20 minutes  to 3.33 hours) This would still be preferable than 1 block per day (maybe)

[01:51] emdje: When the difficulty based upon current blocktime is not decreased to fast you already have slower blocks

[01:51] dbkeys: Yeah, @leathan , been trying to get a hold of that guy !

[01:51] emdje: thus accounting for decreased demand

[01:51] dbkeys: that is true

[01:51] leathan: thats what i meant by "double" elastic on the forum by the way. dynamic block time // reward

[01:52] leathan: witha clear target like dbkeys said on 2mins

[01:52] dbkeys: the thing is that if a KGW/ DGW algo mereley adjust the diff down, then very little (relatively speaking) hashpower is securing the transactions.

[01:53] dbkeys: it should indeed gradually adjust the diff down, but perhaps not so low that block production reaches the fastest nominal 2 min time interval between blocks

[01:53] dbkeys: maybe a 10x slowdown to 20 minutes block interval time is acceptable to all when hashpower is in a valley

[02:00] dbkeys: thus at least, the reduced hashpower has to work 10x more to produce a block ... but still 20 minutes is ok to wait, when we have been waiting 24 hours in some occasions ..... :O

[02:04] dbkeys: in other words, when network hashpower is low, the block interval time should be higher in order to require that some _minimum_ amount of hash energy be securing every transaction block

[02:56] emdje: What if you would take the ratio between 'normal' blocktime and current blocktime; at this moment that ratio is 2/367.876=.005436558, and thansform that using (Ratio-1)^3. (edited)

[02:58] emdje: When the hashrate goes down fast the ratio becomes negative (approching 0), when up is goes up increasingly fast

[03:02] emdje: transformation of our current ratio is -.9838. Where one could decide to intermittently multiply the difficulty by (4 + -.9838)/4=.754

[03:02] emdje: meaning a reduction to 1472.9

[03:06] emdje: The subsequent ratio, when hashrate stays the same, is .00721

[03:12] emdje: hmm I see that hashrate is adjusted to fast on the low side

[03:23] emdje: (Ratio-1)^x      Inceasing x means that the extremes are adjusted more

[03:24] emdje: Don't know if it is useful, but this is what I just cooked up using excel :stuck_out_tongue:

Not sure where you see a stubborn refusal to fix the difficulty problem when I just mentioned more than once recently in this thread that we have three people working on the 'zmark' chain testing algorithms.

I'm quite confident in Poloniex personally.

Sorry to hear that the high difficulty has given you a bad experience so far. We definitely don't intend for marking to be a niche market thing though.

Miners will mine whatever is profitable for them to mine, so if we can create demand for BTM then the mining will follow.

It's a lot less dangerous with the difficulty stuck as high as it is right now, as the cost to attack would be quite significant relative to other altcurrencies.

Right now there's no incentive other than speculation anyway, and people can still do that on Poloniex if they wish. One way or the other it will get resolved sometime in the near future. Either economically by demand increasing naturally as things are developed, or putting a buywall at a price sufficient for miners to mine. Or technically through a hard fork to a new algorithm as a result of the research being done by dbkeys, leathan, and ecucoin on their Pfennig fork's blockchain('zmark').

I don't know but I'm pretty sure the version I got was the latest verison that's not the 2.0 beta. I just followed the instructions on the electrum website to install it. probably apt-get or something, i don't remember if i downloaded a package or just did it that way, but I'm thinking it was apt-get.

I don't think it's 'fine'. But I also know that it's less important than getting people working on Bitmark and marking and getting an actual product(s) out there. If there's nothing to use, then whether BTM functions properly at all doesn't make much of a difference. But Mark mentioned in Slack a couple of days ago #general that he's working on coming up with a way to get a wall on the market that will restart BTM mining and getting the Bitmark Foundation funded and actively contributing to making things happen. So I'm confident that he's working to address both of these issues right now at the same time, BTM/mining and marking itself.

Someone dumping on Bittrex wouldn't result in much of a change as the price would readjust to whatever the market felt was a fair value at that time.

Plus hopefully Bittrex will delist it soon and we can have Poloniex again as the central point of trade. Having a thin market with no volume like the one on Bittrex doesn't add much value imo. In the future when there's demand and volume I'm sure Bittrex will have no problem readding BTM if needed.  

Thing is with Bitmark all our intended significant usage is meant to happen off-chain anyway. So in the very short term it's not really going to matter. Getting people mining it is as simple as putting up a sufficient amount of BTC at whatever price it takes to make it profitable for miners.

No change in the algorithm yet, as we've yet to really go through a period of demand to see whether it will perform as intended. But there are people working on a new chain right now testing some potential changes if necessary.

Don't tell me you of all people, someone who's been here posting about various scams for the last little while as fallen for Paycoin of all things?!

That's exactly what happened with Ghash too. Zero fees and >50% hashing.

And then before that we had Deepbit over 50, and BTCGuild dangerously close to 50%.

Maybe PoS isn't in it's final fully robust form yet, but I think it sounds pretty solid. Someone could borrow or rent miners in PoW too. Or hack a pool like Ghash. And in PoS people get bent out of shape when they see a single account with 4-5% of supply when Bitcoin itself has had 3 separate mining pools around 50% already.

You mean Melvin, not Mark right?

Personally I don't see marking as tipping at all. At least I don't plan to integrate marking in to my platform as a form of tipping.

People aren't renting miners because there's no point in renting miners. A lot of people don't see the network as a problem right now, as reduced supply is a good thing while things are still getting going.

I think the network will be fixed through a market based solution rather than through renting a bunch of hash. Renting hash is a temporary solution, but a healthy market with people buying marks is a long term one.

I think borrowing coins/leased forging and such is the only major danger that I've seen thus far to a solid PoS set up like NXT. In general I think PoS communities need to be vigilant about discouraging mass lending as it seems to be the only plausible way that an attacker could gain a sufficient amount of stake.

Seems everyone has their own different interpretation of what's going on from what Mark has said.


Not sure how you see any sort of move towards centralisation. I had been saying since Mark was sick that we should try to get everything that the project needs out and on paper so we can begin to break it down in to manageable steps and tasks. Getting more people who want to be involved working on things will help decentralise the work load. We saw how things ground to a halt and how quiet it was when Mark was sick. I'd rather have a technical description of what it's going to take to make marking a reality out there and not just in Mark's head, so that people can work together to make it a reality.


Well half of the coins from the last low difficulty phase are already mature so I doubt another 7k BTM maturing is going to have too much of an effect on the market. If it was a single person and they sold it all off immediately or something then maybe.

Were you not able to gather enough testnet stake to test your theories?

He is using testnet as well. In fact he's just been working on NXT testnet at the request of many. I'm guessing you haven't read the thread thus far. He's doing a good job so far and lots of people are interested in seeing more of his attempts.

This type of thing is critical for PoS to really be considered a robust consensus system. Actually it's not great that it's taken this long for some good public stress testing/attacks. Anyone interested in the idea of PoS should be supporting people who can help strengthen it.

He has shown how he owned APEX.

Are you Jones from the Jay framework?