done

Code=DTC
Name=datacoin
Webpage=datacoin.info
Explorer=www.bytestamp.net/blocks/index
Example address=any of these: www.bytestamp.net/blocks/lunsp
Conflicts=already listed on CMC - coinmarketcap.com/currencies/datacoin
Reddit=www.reddit.com/r/Datacoin but its dead

Empoex trading Datacoin.

I see
https://empoex.com/trade/DTC-BTC

It seems to be live.  Anybody have any experience?

Woops!

Sorry.

Maybe somebody can help.

I was chatting to Embii on the Facebook page of Apertus.io.  He mentioned that they are able to get Javascript programs to run on Datacoin but only with the 20byte payload, not the full 128kB payload.  They can write the data, but no other client can read it.  With the 20byte payload it is very expensive to write Javascript programs into the Datacoin blockchain (you need to pay 0.05DTC for every chunk of code that gets written and with 20bytes you need a lot of chunks).

From embii:
"we implemented encoding and deciding base 64 for DataCoin...we did get this to work...except what is saved in this manner is only accessible via RPC to the wallet that saved it... this is the real problem and is the main reason we abandoned it. It does have personal applications but does not let you share anything saved with others."

I tried to see if I could find the problem in the Datacoin wallet.  In rpcwallet.cpp I saw

senddata(const Array& params, bool fHelp)
{
if (fHelp || 1 != params.size())
throw runtime_error(
"senddata [data]\n"
"<data> is a base64 encoded data chunk"
+ HelpRequiringPassphrase());

CWalletTx wtx;

// Transaction data
std::string txdata;
if (params.size() > 0 && params[0].type() != null_type && !params[0].get_str().empty()) {
txdata = params[0].get_str();
if (txdata.length() > MAX_TX_DATA_SIZE)
throw JSONRPCError(RPC_INVALID_PARAMETER, "data chunk is too long. split it the payload to several transactions.");
}

string strError = pwalletMain->SendData(wtx, false, txdata);
if (strError != "")
throw JSONRPCError(RPC_WALLET_ERROR, strError);

return wtx.GetHash().GetHex();
}


I suspect HelpRequiringPassphrase() is the suspect. Anybody else have an idea?  We will have to remove this so that other wallets can see the 128kB data in the blockchain.
If this can be done the Datacoin blockchain will contain Javascript programs that will be visible to other clients and executable in the Apertus.io browser.  And maybe other browsers as well.  Datacoin could then use Javascript as a programming language.

Hello,


    I see this in src/rpcwallet.cpp.

    Are you telling me the ~128KiB data blob is only accessible with the private key of the spender and that the wallet.dat must be encrypted too?

    If so... couldn't there be some work-arounds where an M-of-N Datacoin address could be employed to make the ~128KiB blobs available to anybody at the time of publication whereby the publisher says, "BTW, here's the WIF for those so you can decode them."

Best Regards,
-Chicago

I'm not sure why your correspondent would think that. Certainly senddata must allow the user to provide a password for unlocking an encrypted wallet but there isn't any such requirement for getdata:

https://github.com/foo1inge/datacoin-hp/commit/791125b901767b9dec40e04f6865181a3276395b#diff-e75eff0ce0dde388eddbe3173db85bd4R320


Or am I missing something fundamental?

Cheers

Graham

Hi Graham,

    I wish there had been a change to the CLIENT_NAME in src/version.cpp or an incremental update to the CLIENT_VERSION_REVISION in src/clientversion.h because when I look at the peers today, I see 3x as many nodes runningSatoshi:0.8.3/ (datacoin-hp) as I see runningSatoshi:0.8.5/ (datacoin) and I can't tell which are running from the datacoin-project repository and which are running from foo1inge's repository.

    I will try the datacoin-project repository fork of datacoin-hp (named datacoin) once more and figure out why I had stopped using it.  If I am remembering correctly, there was something I didn't find working quite as well as on the foo1inge datacoin-hp repo.

    Since there seems to be some more interest here in Datacoin overall, I share this information in goodwill.
    Running the DatacoinMiner with setsievepercentage 40 and setsieveextensions 4 has yielded me a significant improvement in chains per day with the level of difficulty we have been seeing over the past few months.

    Are those sieve values very different from your own optimizations?

Best Regards,
-Chicago

Mr Higgins I work on old Celeron laptops and I have mined tens of thousands of Datacoin.  The difficulty is currently 6.98, so you get about 500 DTC every day from an ordinary computer.

To be honest, I would respectfully differ on changing the Datacoin abbreviation.  I like the idea of saying 100 DTC instead of 100 DATA.

The Apertus.io project tried very hard to get Datacoin to work with their project.  The Storj founder super3 did the same thing with Metadisk, but he wanted to create his own coin.  The Apertus.io people want to work with existing coins, and Datacoin and Apertus seem handmade for each other.  Javascript programs on the Datacoin blockchain that execute when it is browsed is a mouth watering idea.  It would finally unlock the unique promise of Datacoin, which lies in those 128kB.  They did not change the client, and it seems as if they do not have a C++ programmer amongst them.  I may be wrong, but it would have been easier if such a person had produced his own version of the client.  

So we have to figure this out somehow and produce an updated client.

This is a problem in senddata, not getdata.  The Apertus.io people insist they cannot read Javascript programs etched on the Datacoin blockchain with senddata.  It could only be read by the client that etched it.  So we have to drop the encryption in senddata.

Data is stored *unencrypted* inside the blockchain, unless you encrypt it by your own means. Data can be posted RAW or using the envelope protocol (defined by OP).
I wrote a tool some time ago to read both types of data from a running datacoind using RPC calls .