[ANN] [PPC] PPCoin Released! - First Long-Term Energy-Efficient Crypto-Currency

[Jutarul]

I am just going to drop a cross-reference here with respect to a recent heated debate in the bitcoin community with respect to the eternal cost of unspendable outputs, because ppcoin in principle is affected by the same deficiency:
https://bitcointalk.org/index.php?topic=150493.0

If bitcoin doesn't come up with a solution to this problem, it may be worth investigating how ppcoin can introduce innovative features to accommodate the issue.

[Sunny King]

I am just going to drop a cross-reference here with respect to a recent heated debate in the bitcoin community with respect to the eternal cost of unspendable outputs, because ppcoin in principle is affected by the same deficiency:
https://bitcointalk.org/index.php?topic=150493.0

If bitcoin doesn't come up with a solution to this problem, it may be worth investigating how ppcoin can introduce innovative features to accommodate the issue.

I was aware of this issue so ppcoin has a minimum txout value of 1 cent. To think that such 'micropayment' should be supported on block chain is unrealistic in my opinion.

Although I think it's inaccurate to call it unspendable, it supposedly can be spent together with some other coins (txout), or combined when you consolidate the wallet due to fragmentation (too many small coins in wallet causing performance issues).

[Jutarul]

I was aware of this issue so ppcoin has a minimum txout value of 1 cent. To think that such 'micropayment' should be supported on block chain is unrealistic in my opinion.

You're referring to the reference client behavior. However, (I didn't check it) I assume that those transactions are still valid and could make it into the blockchain, correct?

Although I think it's inaccurate to call it unspendable, it supposedly can be spent together with some other coins (txout), or combined when you consolidate the wallet due to fragmentation (too many small coins in wallet causing performance issues).

Yes. A more concise description is "economically unfeasible" outputs, where you effectively spent more on redeeming than they're worth.

[Sunny King]

You're referring to the reference client behavior. However, (I didn't check it) I assume that those transactions are still valid and could make it into the blockchain, correct?

No in ppcoin it's enforced in block check that txout value must be at least 1 cent. If you create such a transaction manually it will fail CheckTransaction().

[Jutarul]

You're referring to the reference client behavior. However, (I didn't check it) I assume that those transactions are still valid and could make it into the blockchain, correct?

No in ppcoin it's enforced in block check that txout value must be at least 1 cent. If you create such a transaction manually it will fail CheckTransaction().

wow. so what you're saying is that the minimum amount you can spent with ppcoin is bounded by the transaction fee?

I think there are some unnecessary statements in the source code which are due to different policies overlapping.
E.g.

Code:

        // To limit dust spam, require MIN_TX_FEE/MIN_RELAY_TX_FEE if any output is less than 0.01                                                                                               
        if (nMinFee < nBaseFee)
        {
            BOOST_FOREACH(const CTxOut& txout, vout)
		if (txout.nValue < CENT)
                    nMinFee = nBaseFee;
        }

vs.

Code:

        if ((!txout.IsEmpty()) && txout.nValue < MIN_TXOUT_AMOUNT)
            return DoS(100, error("CTransaction::CheckTransaction() : txout.nValue below minimum"));

[Sunny King]

Right the code on the top is from bitcoin but I didn't remove it when I introduced the minimum txout value. The bitcoin logic you quoted is no longer used. Actually it's already obsolete when I enforced transaction fees throughout, i.e. ppcoin has no free transaction so nMinFee cannot be less than nBaseFee.

[Sunny King]

I think Misterbigg made a good point there that the 1 satoshi output is not going to be recycled because it cost more in fees to recycle them than their total value. I am not sure if this is what's happening on bitcoin, but there is a chance that the wallet consolidation would fail at the end, leaving thousands of those tiny outputs unable to be consolidated because there is not enough left to pay the fee, and then people just throw it away.

But anyways, ppcoin doesn't have this particular issue.

[Jutarul]

But anyways, ppcoin doesn't have this particular issue.

Foresight or serendipity ? 

[Sunny King]

It's much less costly to spam a new coin so I had to strengthen this part to counter certain class of spamming attack. Although people would argue that allowing tiny output value may open up to some good applications but in my opinion spamming is a serious issue so micropayment has to go.

[Jutarul]

It's much less costly to spam a new coin so I had to strengthen this part to counter certain class of spamming attack. Although people would argue that allowing tiny output value may open up to some good applications but in my opinion spamming is a serious issue so micropayment has to go.

a wise decision.

[EskimoBob]

Glad to see how PPC keeps moving on right direction and learning from btc mistakes. Few can do that.
Any thoughts on how to avoid the absurd situation BTC is or will be in with it's massive block chain? Installing an official BTC QT client now days is not a small task because of the huge download requirements (and it's getting worst by the minute). I still believe that big files are fragile files. 
I only ask because I see the ugly trend in BTC, where the complete transaction data will be available for only the select few. Rest of us have to rely on bits of data made available via some "middleware" ("explorers"), controlled by those few... stinks like bank... hold on, *coin supposed to free us from the central control!

Cheers!

[Sunny King]

Glad to see how PPC keeps moving on right direction and learning from btc mistakes. Few can do that.
Any thoughts on how to avoid the absurd situation BTC is or will be in with it's massive block chain? Installing an official BTC QT client now days is not a small task because of the huge download requirements (and it's getting worst by the minute). I still believe that big files are fragile files. 
I only ask because I see the ugly trend in BTC, where the complete transaction data will be available for only the select few. Rest of us have to rely on bits of data made available via some "middleware" ("explorers"), controlled by those few... stinks like bank... hold on, *coin supposed to free us from the central control!

Cheers!

Regarding block chain size, I observe there are a couple lines of possible development in this front:

1) Ultraprune in bitcoin (large downloadable checkpoint of unspent outputs)
2) Balance based ledger block (this approach seems to have been taken by ripple)
3) Relocating unspent outputs forward in block chain

I am favoring 3) because of ease of implementation. Overall I think the most efficient is probably 2) but it's a costly redesign for bitcoin.

Regarding block size limit, it was put in there to prevent premature growth of block chain size. As you said, people have trouble doing the initial download because it's too intensive on the computer. We need more time for average PC to catch up to the job, to raise block size limit before that happens is going to make average node feeling the pain. The hardware more suitable for future bitcoin full node is: Terabyte SSD to accommodate the active part of block chain plus entire block index. Internet access preferably 100Mbps symmetric. This will allow bitcoin to begin competing against networks such as paypal in terms of transaction volume without sacrificing decentralization.

It's a tough decision, we'll see what happens with bitcoin. There is speculations going on that if bitcoin delays raising block size limit then transaction volume is going to flow to litecoin because at the current limit litecoin can handle 4x the transaction volume of bitcoin (bitcoin needs to raise block size limit to 4MB to match litecoin). The problem is that litecoin would have the exact same issues bitcoin network has in this situation.

[irritant]

It's much less costly to spam a new coin so I had to strengthen this part to counter certain class of spamming attack. Although people would argue that allowing tiny output value may open up to some good applications but in my opinion spamming is a serious issue so micropayment has to go.

what is considered a micropayment? , or different question: what is the smallest amount possible to pay?  wouldnt this just make the number of digits behind the dot less   (0.0001 instead of 0.00000001)?   I dont really understand most of this , probably should read more about it .. my guess would be a micropayment is the smallest possible amount you're able to send, so i just dont really understand "micropayment has to go"  , if you are making micropayments bigger, they are still micropayments , no?   i guess im wrong here and there..

[killerstorm]

Regarding block chain size, I observe there are a couple lines of possible development in this front:

1) Ultraprune in bitcoin (large downloadable checkpoint of unspent outputs)
2) Balance based ledger block (this approach seems to have been taken by ripple)
3) Relocating unspent outputs forward in block chain

I am favoring 3) because of ease of implementation.

Initial blockchain download is necessary only to verify that current UTXO set is correct.

If that isn't your concern, you can just get current UTXO set and hope it is correct.

So (3) solves approximately nothing.

The best approach is for miners to maintain UTXO set in form of a tree and link it from blocks.

This way anybody can do anything they want without even downloading the whole thing.

[Sunny King]

Regarding block chain size, I observe there are a couple lines of possible development in this front:

1) Ultraprune in bitcoin (large downloadable checkpoint of unspent outputs)
2) Balance based ledger block (this approach seems to have been taken by ripple)
3) Relocating unspent outputs forward in block chain

I am favoring 3) because of ease of implementation.

Initial blockchain download is necessary only to verify that current UTXO set is correct.

If that isn't your concern, you can just get current UTXO set and hope it is correct.

So (3) solves approximately nothing.

The best approach is for miners to maintain UTXO set in form of a tree and link it from blocks.

This way anybody can do anything they want without even downloading the whole thing.

You are too quick dismissing the 3rd option. If everyone gets current UTXO set and trusting other nodes for it what's the implication on security and decentralization?

Where option 3) allows us stay true to the current security model where checkpoints and active part of the block chain guarantees your block index to be correct.

[Sunny King]

what is considered a micropayment? , or different question: what is the smallest amount possible to pay?  wouldnt this just make the number of digits behind the dot less   (0.0001 instead of 0.00000001)?   I dont really understand most of this , probably should read more about it .. my guess would be a micropayment is the smallest possible amount you're able to send, so i just dont really understand "micropayment has to go"  , if you are making micropayments bigger, they are still micropayments , no?   i guess im wrong here and there..

It's true that ppcoin effectively only accounts to cent, although it can support upto uPPC (1 millionth) in calculations. This allows users to send amounts like 0.010001, so they still have some room for their 'micro-transaction communications'. Also makes it easier to lower the minimum txout value in a hard fork.

By having a minimum send value enforced, it just means ppcoin does not support sub-cent micropayments. So far nobody has complained this to me, so I think really the impact to users is minimal.

[AndyRossy]

and yes I think there is also an issue of micro change in the btc client btw.

[sangaman]

Thanks for your continued hard work on this project, Sunny, and congrats on patching up the vulnerability over generating POS blocks. I'm still a believer in POS as an efficient solution for cryptocurrency and I think PPC is an honest and promising implementation, much moreso than NVC it seems.

Is there any update on when we can expect PPC to move off checkpointing? It will be a big step forward.

My wishlist for PPC right now is a rebranding/redesign of the name and website. I've noted here before that "pee pee cee" and "pee pee coins" are clunky-sounding when spoken out loud. I'd rather have a name that highlights the coins unique features, such as energy-efficiency, and doesn't have any negative or humorous connotations. "GreenCoin" or "StakeCoin" are some simple names that come to mind, but there are probably better potential names that are more subtle. I'd be happy to brainstorm some more if you're interested. I strongly believe a different name could help a lot in appealing to a broader base of users.

I'd also love if the website were cleaner and simpler and presented more information about PPC in a straightforward and succinct manner. Currently there is just the white paper and I don't expect the casual browser to go into any detail reading that. The website is responsible for many important first impressions and currently it is cryptic and confusing.

I'd be more than happy to help with any of this, I do some web design and I wouldn't mind contributing towards the redesign of a website. Feel free to contact me.

[mech]

Thanks for your continued hard work on this project, Sunny, and congrats on patching up the vulnerability over generating POS blocks. I'm still a believer in POS as an efficient solution for cryptocurrency and I think PPC is an honest and promising implementation, much moreso than NVC it seems.

Is there any update on when we can expect PPC to move off checkpointing? It will be a big step forward.

My wishlist for PPC right now is a rebranding/redesign of the name and website. I've noted here before that "pee pee cee" and "pee pee coins" are clunky-sounding when spoken out loud. I'd rather have a name that highlights the coins unique features, such as energy-efficiency, and doesn't have any negative or humorous connotations. "GreenCoin" or "StakeCoin" are some simple names that come to mind, but there are probably better potential names that are more subtle. I'd be happy to brainstorm some more if you're interested. I strongly believe a different name could help a lot in appealing to a broader base of users.

I'd also love if the website were cleaner and simpler and presented more information about PPC in a straightforward and succinct manner. Currently there is just the white paper and I don't expect the casual browser to go into any detail reading that. The website is responsible for many important first impressions and currently it is cryptic and confusing.

I'd be more than happy to help with any of this, I do some web design and I wouldn't mind contributing towards the redesign of a website. Feel free to contact me.

GreenCoin, good idea! May be "ECOin" ?

[irritant]

i thought the name cannot be changed (in the beginning people didnt like the name because it made them think of paypal, and than some , but for some reason it isnt changable) , and there is also terracoin claiming to be green.  ... i'm not sure tho , still i think ppcoin has gotten some awareness which will be lost, with name changing


edit: you already asked 6 months ago https://bitcointalk.org/index.php?topic=101820.msg1242503#msg1242503