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Author Topic: NXT :: descendant of Bitcoin - Updated Information  (Read 2761529 times)
2Kool4Skewl (OP)
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February 28, 2014, 07:27:44 AM
 #38821

lock the posts at 2100 pages Grin


lol   Grin


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TRUSTEE 
There are several different types of Bitcoin clients. The most secure are full nodes like Bitcoin Core, but full nodes are more resource-heavy, and they must do a lengthy initial syncing process. As a result, lightweight clients with somewhat less security are commonly used.
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wakasaki808
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February 28, 2014, 07:28:53 AM
 #38822

lock the posts at 2100 pages Grin


lol   Grin

dooooo ittttttt! Tongue
ZeroTheGreat
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February 28, 2014, 07:31:15 AM
 #38823

That's a BS answer. According to Ripple Labs they will be just as decentralized as NXT is in the future.
Mmm, big amount of (less and less interdependant) validators'll destroy your precious 3 sec. Sad, but true. Low amount of validators - no decentralization at all.
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February 28, 2014, 07:35:39 AM
 #38824

Sorry, BTT's actually more comfortable for reading. At least for me.
wakasaki808
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February 28, 2014, 07:41:12 AM
 #38825

Sorry, BTT's actually more comfortable for reading. At least for me.

did you try all the different board themes with nxtcrypto?
abctc
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February 28, 2014, 07:43:02 AM
 #38826

Hey I have a question with transaction malleability.  From the NXT Wiki:
Quote
Transaction malleability is an issue with Nxt, as it is with all cryptocurrencies. Do not rely on a transaction ID alone to verify transactions!
...  So if an exchange should not rely on just looking for a transactionID, what is the proper method?  Do they have to attempt to track sendingAccountID, receivingAccountId, and amount?
- there was the CfB's answer:
It's a problem only for exchanges that rely solely on transaction id. It doesn't need to be fixed. An exchange is supposed to pay attention to timestamp and other parameters of a transaction.
what parameters ,except timestamp?
Amount or ReferencedTransaction.

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, the Next platform.  Magis quam Moneta (More than a Coin)
CIYAM
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February 28, 2014, 07:50:12 AM
 #38827

I would think ReferencedTransaction would be the most convenient (perhaps being always a previous one that has already confirmed although better not to be hard-coded otherwise it might fail after blockchain pruning).

With CIYAM anyone can create 100% generated C++ web applications in literally minutes.

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2Kool4Skewl (OP)
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February 28, 2014, 08:16:30 AM
 #38828

I'm trying to simulate TF using Ian's program if we limit all accounts to a 1% forge balance.  Using 100 accounts holding 1% of the currency over a ten year period, I'm getting a combined best streak of ~23.  This is combining the first 50 accounts.  (These are the accounts assumed to be under the same control.)

Code:
// Copyright (c) 2014 CIYAM Developers
//
// Distributed under the MIT/X11 software license, please refer to the file license.txt
// in the root project directory or http://www.opensource.org/licenses/mit-license.php.

#include <ctime>
#include <cmath>
#include <cstdlib>

#include <string>
#include <vector>
#include <sstream>
#include <iostream>

//#define NUM_DAYS 1
#define NUM_YEARS 10

#define PENALISE_HIGHER_STAKE
//#define PREVENT_IMMEDIATE_REPEAT

//#define SHOW_WINNERS
//#define SHOW_WINNERS_WEIGHT

using namespace std;

const int c_combined_proportion = 2;

#ifndef NUM_YEARS
const size_t c_num_blocks = 1440 * NUM_DAYS;
#else
const size_t c_num_blocks = 1440 * 365 * NUM_YEARS;
#endif

int main( )
{
#ifdef SHOW_WINNERS
   string winners;
#endif
   vector< int > wins;
   vector< int > streaks;
   vector< int > balances;
   vector< int > penalised;
   vector< int > penalising;
   vector< int > best_streak;

   vector< int > combined;
   vector< long > weights;

   long total_balance = 0;

   int combined_streak = 0;
   int best_combined_streak = 0;

   balances.push_back( 1 );
   balances.push_back( 1 );
   balances.push_back( 1 );
   balances.push_back( 1 );
   balances.push_back( 1 );
   balances.push_back( 1 );
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   balances.push_back( 1 );
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   balances.push_back( 1 );
   balances.push_back( 1 );
   balances.push_back( 1 );
   balances.push_back( 1 );
   balances.push_back( 1 );
   balances.push_back( 1 );
   balances.push_back( 1 );
   balances.push_back( 1 );
   balances.push_back( 1 );
   balances.push_back( 1 );
   balances.push_back( 1 );
   balances.push_back( 1 );
   balances.push_back( 1 );
   balances.push_back( 1 );
   balances.push_back( 1 );
   balances.push_back( 1 );
   balances.push_back( 1 );
   balances.push_back( 1 );
   balances.push_back( 1 );

   srand( ( unsigned int )time( 0 ) );

   for( size_t i = 0; i < balances.size( ); i++ )
   {
      total_balance += balances[ i ];

      wins.push_back( 0 );
      weights.push_back( 0 );
      streaks.push_back( 0 );
      combined.push_back( 0 );
      penalised.push_back( 0 );
      penalising.push_back( 0 );
      best_streak.push_back( 0 );
   }

   size_t last_winner = 0;
   for( size_t blocks = 0; blocks < c_num_blocks; blocks++ )
   {
      long total_weight = 0;
      for( size_t i = 0; i < weights.size( ); i++ )
      {
         if( penalising[ i ] )
         {
            --penalising[ i ];
            weights[ i ] = 0;
         }
         else
         {
            int divisor = rand( ) % 10;

            if( divisor == 0 )
               ++divisor;

            weights[ i ] = ( rand( ) % 10000 ) * ( balances[ i ] / divisor );

            if( weights[ i ] == 0 )
               ++weights[ i ];

            total_weight += weights[ i ];
         }
      }

      if( total_weight == 0 )
         ++total_weight;

      size_t winner = 0;
      size_t runner_up = 0;
      long best_target = 0;
      long second_best_target = 0;

      for( size_t i = 0; i < balances.size( ); i++ )
      {
         long adjusted_weight = weights[ i ] * 1000 / total_weight;

         if( adjusted_weight > best_target )
         {
            winner = i;
            best_target = adjusted_weight;
         }
         else if( adjusted_weight > second_best_target )
         {
            runner_up = i;
            second_best_target = adjusted_weight;
         }
      }

#ifdef PENALISE_HIGHER_STAKE
      if( best_target == 350 ) // an above median value
      {
         ++penalised[ winner ];
         penalising[ winner ] = 1440;
      }
#endif

#ifdef PREVENT_IMMEDIATE_REPEAT
      if( winner == last_winner )
         winner = runner_up;
#endif

#ifdef SHOW_WINNERS
      winners += ( char )( 'a' + winner );
#  ifdef SHOW_WINNERS_WEIGHT
      ostringstream osstr;
      osstr << best_target;
      winners += "(" + osstr.str( ) + ")";
#  endif
#endif
      ++wins[ winner ];

      if( winner < balances.size( ) / c_combined_proportion )
      {
         ++combined_streak;
         if( combined_streak > best_combined_streak )
            best_combined_streak = combined_streak;
      }
      else
         combined_streak = 0;

      if( winner == last_winner )
      {
         ++streaks[ winner ];
         if( streaks[ winner ] > best_streak[ winner ] )
            best_streak[ winner ] = streaks[ winner ];
      }
      else
         streaks[ winner ] = 0;

      last_winner = winner;
   }

   cout << "blocks = " << c_num_blocks << endl;

   for( size_t i = 0; i < balances.size( ); i++ )
      cout << ( char )( 'a' + i ) << " = " << balances[ i ] << endl;

#ifdef SHOW_WINNERS
   cout << winners << endl;
#endif
   for( size_t i = 0; i < wins.size( ); i++ )
      cout << "wins( " << ( char )( 'a' + i ) << " ) = " << wins[ i ] << endl;

#ifdef PENALISE_HIGHER_STAKE
   for( size_t i = 0; i < penalised.size( ); i++ )
      cout << "penalised( " << ( char )( 'a' + i ) << " ) = " << penalised[ i ] << endl;
#endif

   for( size_t i = 0; i < best_streak.size( ); i++ )
      cout << "best_streak( " << ( char )( 'a' + i ) << " ) = " << ( best_streak[ i ] + 1 ) << endl;

   cout << "best_combined_streak = " << best_combined_streak << endl;
   cout << "(combined the first " << ( balances.size( ) / c_combined_proportion ) << " accounts)" << endl;
   cout << balances.size() << endl;
}


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TRUSTEE 
ChuckOne
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February 28, 2014, 08:18:33 AM
 #38829

Just a reminder: BCNext don't want NXT to be a currency. Coins on top of Nxt should be. Does this change anything?

Does this change anything regarding instant confirmation discussion?

No.
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February 28, 2014, 08:19:45 AM
 #38830

did you try all the different board themes with nxtcrypto?
Maybe I'll look for it and'll try it someday. I like use things "as is" very often.
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February 28, 2014, 08:21:25 AM
 #38831

did you try all the different board themes with nxtcrypto?
Maybe I'll look for it and'll try it someday. I like use things "as is" very often.

Please try out the "prosilver" theme at least, before making a judgement.

It is SO much better and will probably be a mind-changer Smiley

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February 28, 2014, 08:26:11 AM
 #38832

I'm trying to simulate TF using Ian's program if we limit all accounts to a 1% forge balance.  Using 100 accounts holding 1% of the currency over a ten year period, I'm getting a combined best streak of ~23.  This is combining the first 50 accounts.  (These are the accounts assumed to be under the same control.)

That's not too bad at all really - it basically gives us a rough idea that for huge transfer amounts (where you might be concerned with such a possible attack) you would want to require 30+ confirmations (around half the time of the average 6 confirmations for Bitcoin).

You might also want to experiment with different amounts of collusion (there should be a constant in the code that is used to determine the proportion of that).

With CIYAM anyone can create 100% generated C++ web applications in literally minutes.

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hehe


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February 28, 2014, 08:26:24 AM
 #38833

When the test is completed AE? Roll Eyes
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February 28, 2014, 08:28:01 AM
 #38834

Any luck with the decentralized exchange? Seems like a hot buzz word across the crypto community, but not much content.

We are testing it.
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February 28, 2014, 08:32:24 AM
 #38835

When the test is completed AE? Roll Eyes

When we are confident that it is secure?
wakasaki808
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February 28, 2014, 08:34:46 AM
 #38836

did you try all the different board themes with nxtcrypto?
Maybe I'll look for it and'll try it someday. I like use things "as is" very often.

well if you ever decide to and have an account there.

Its https://forums.nxtcrypto.org/ucp.php -> "Board Preferences" -> "My board style:" -> Then just look through the 5 different styles available.
2Kool4Skewl (OP)
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February 28, 2014, 08:47:37 AM
 #38837

I'm trying to simulate TF using Ian's program if we limit all accounts to a 1% forge balance.  Using 100 accounts holding 1% of the currency over a ten year period, I'm getting a combined best streak of ~23.  This is combining the first 50 accounts.  (These are the accounts assumed to be under the same control.)

That's not too bad at all really - it basically gives us a rough idea that for huge transfer amounts (where you might be concerned with such a possible attack) you would want to require 30+ confirmations (around half the time of the average 6 confirmations for Bitcoin).

You might also want to experiment with different amounts of collusion (there should be a constant in the code that is used to determine the proportion of that).


I edited the code and added a constant, c_combined_percent, to determine the proportion of accounts in collusion.  Assuming all nodes are limited to 1% forge power over a ten year period and a ninety percent collusion rate, I'm getting a combined best streak of 151, 137 and 136 from three runs.

Code:
// Copyright (c) 2014 CIYAM Developers
//
// Distributed under the MIT/X11 software license, please refer to the file license.txt
// in the root project directory or http://www.opensource.org/licenses/mit-license.php.

#include <ctime>
#include <cmath>
#include <cstdlib>

#include <string>
#include <vector>
#include <sstream>
#include <iostream>

//#define NUM_DAYS 1
#define NUM_YEARS 10

#define PENALISE_HIGHER_STAKE
//#define PREVENT_IMMEDIATE_REPEAT

//#define SHOW_WINNERS
//#define SHOW_WINNERS_WEIGHT

using namespace std;

const int c_combined_proportion = 10;
const double c_combined_percent = 90;

#ifndef NUM_YEARS
const size_t c_num_blocks = 1440 * NUM_DAYS;
#else
const size_t c_num_blocks = 1440 * 365 * NUM_YEARS;
#endif

int main( )
{
#ifdef SHOW_WINNERS
   string winners;
#endif
   vector< int > wins;
   vector< int > streaks;
   vector< int > balances;
   vector< int > penalised;
   vector< int > penalising;
   vector< int > best_streak;

   vector< int > combined;
   vector< long > weights;

   long total_balance = 0;

   int combined_streak = 0;
   int best_combined_streak = 0;

   for(int a=0;a<100;a++){
   balances.push_back( 1 );
   }

   srand( ( unsigned int )time( 0 ) );

   for( size_t i = 0; i < balances.size( ); i++ )
   {
      total_balance += balances[ i ];

      wins.push_back( 0 );
      weights.push_back( 0 );
      streaks.push_back( 0 );
      combined.push_back( 0 );
      penalised.push_back( 0 );
      penalising.push_back( 0 );
      best_streak.push_back( 0 );
   }

   size_t last_winner = 0;
   for( size_t blocks = 0; blocks < c_num_blocks; blocks++ )
   {
      long total_weight = 0;
      for( size_t i = 0; i < weights.size( ); i++ )
      {
         if( penalising[ i ] )
         {
            --penalising[ i ];
            weights[ i ] = 0;
         }
         else
         {
            int divisor = rand( ) % 10;

            if( divisor == 0 )
               ++divisor;

            weights[ i ] = ( rand( ) % 10000 ) * ( balances[ i ] / divisor );

            if( weights[ i ] == 0 )
               ++weights[ i ];

            total_weight += weights[ i ];
         }
      }

      if( total_weight == 0 )
         ++total_weight;

      size_t winner = 0;
      size_t runner_up = 0;
      long best_target = 0;
      long second_best_target = 0;

      for( size_t i = 0; i < balances.size( ); i++ )
      {
         long adjusted_weight = weights[ i ] * 1000 / total_weight;

         if( adjusted_weight > best_target )
         {
            winner = i;
            best_target = adjusted_weight;
         }
         else if( adjusted_weight > second_best_target )
         {
            runner_up = i;
            second_best_target = adjusted_weight;
         }
      }

#ifdef PENALISE_HIGHER_STAKE
      if( best_target == 350 ) // an above median value
      {
         ++penalised[ winner ];
         penalising[ winner ] = 1440;
      }
#endif

#ifdef PREVENT_IMMEDIATE_REPEAT
      if( winner == last_winner )
         winner = runner_up;
#endif

#ifdef SHOW_WINNERS
      winners += ( char )( 'a' + winner );
#  ifdef SHOW_WINNERS_WEIGHT
      ostringstream osstr;
      osstr << best_target;
      winners += "(" + osstr.str( ) + ")";
#  endif
#endif
      ++wins[ winner ];

      if( winner < (int)((double)balances.size( ) * c_combined_percent / 100.0) )
      {
         ++combined_streak;
         if( combined_streak > best_combined_streak )
            best_combined_streak = combined_streak;
      }
      else
         combined_streak = 0;

      if( winner == last_winner )
      {
         ++streaks[ winner ];
         if( streaks[ winner ] > best_streak[ winner ] )
            best_streak[ winner ] = streaks[ winner ];
      }
      else
         streaks[ winner ] = 0;

      last_winner = winner;
   }

   cout << "blocks = " << c_num_blocks << endl;

   for( size_t i = 0; i < balances.size( ); i++ )
      cout << ( char )( 'a' + i ) << " = " << balances[ i ] << endl;

#ifdef SHOW_WINNERS
   cout << winners << endl;
#endif
   for( size_t i = 0; i < wins.size( ); i++ )
      cout << "wins( " << ( char )( 'a' + i ) << " ) = " << wins[ i ] << endl;

#ifdef PENALISE_HIGHER_STAKE
   for( size_t i = 0; i < penalised.size( ); i++ )
      cout << "penalised( " << ( char )( 'a' + i ) << " ) = " << penalised[ i ] << endl;
#endif

   for( size_t i = 0; i < best_streak.size( ); i++ )
      cout << "best_streak( " << ( char )( 'a' + i ) << " ) = " << ( best_streak[ i ] + 1 ) << endl;

   cout << "best_combined_streak = " << best_combined_streak << endl;
   cout << "(combined the first " << ( (double)balances.size( ) * c_combined_percent / 100.0 ) << " accounts)" << endl;
   cout << balances.size() << endl;
}



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TRUSTEE 
Labteck
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February 28, 2014, 08:57:37 AM
 #38838

This 2000 post thrad is madness...please consider to CLOSE IT, with a last message like "go to forum nxccrypto" or something like that.

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       VIORCOIN[by_conty] ▄████████████████████████████████████████████████████████▄
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        Make International Calls
      Cheap and More Secure
2Kool4Skewl (OP)
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February 28, 2014, 08:59:21 AM
 #38839

I'm trying to simulate TF using Ian's program if we limit all accounts to a 1% forge balance.  Using 100 accounts holding 1% of the currency over a ten year period, I'm getting a combined best streak of ~23.  This is combining the first 50 accounts.  (These are the accounts assumed to be under the same control.)

That's not too bad at all really - it basically gives us a rough idea that for huge transfer amounts (where you might be concerned with such a possible attack) you would want to require 30+ confirmations (around half the time of the average 6 confirmations for Bitcoin).

You might also want to experiment with different amounts of collusion (there should be a constant in the code that is used to determine the proportion of that).


I edited the code and added a constant, c_combined_percent, to determine the proportion of accounts in collusion.  Assuming all nodes are limited to 1% forge power over a ten year period and a ninety percent collusion rate, I'm getting a combined best streak of 151, 137 and 136 from three runs.

Compare this to allowing an unlimited amount of forging power per account.  If you assign ninety-one percent of the currency to one account and run the test over a ten year period, the account with 91% of the currency gets best streak of 468, 419, 415.  These streaks are three times longer than if you limit accounts to 1% forging power.

Code:
// Copyright (c) 2014 CIYAM Developers
//
// Distributed under the MIT/X11 software license, please refer to the file license.txt
// in the root project directory or http://www.opensource.org/licenses/mit-license.php.

#include <ctime>
#include <cmath>
#include <cstdlib>

#include <string>
#include <vector>
#include <sstream>
#include <iostream>

//#define NUM_DAYS 1
#define NUM_YEARS 10

#define PENALISE_HIGHER_STAKE
//#define PREVENT_IMMEDIATE_REPEAT

//#define SHOW_WINNERS
//#define SHOW_WINNERS_WEIGHT

using namespace std;

const int c_combined_proportion = 10;

#ifndef NUM_YEARS
const size_t c_num_blocks = 1440 * NUM_DAYS;
#else
const size_t c_num_blocks = 1440 * 365 * NUM_YEARS;
#endif

int main( )
{
#ifdef SHOW_WINNERS
   string winners;
#endif
   vector< int > wins;
   vector< int > streaks;
   vector< int > balances;
   vector< int > penalised;
   vector< int > penalising;
   vector< int > best_streak;

   vector< int > combined;
   vector< long > weights;

   long total_balance = 0;

   int combined_streak = 0;
   int best_combined_streak = 0;

   for(int a=0;a<9;a++){
   balances.push_back( 1 );
   }
   balances.push_back(91);

   srand( ( unsigned int )time( 0 ) );

   for( size_t i = 0; i < balances.size( ); i++ )
   {
      total_balance += balances[ i ];

      wins.push_back( 0 );
      weights.push_back( 0 );
      streaks.push_back( 0 );
      combined.push_back( 0 );
      penalised.push_back( 0 );
      penalising.push_back( 0 );
      best_streak.push_back( 0 );
   }

   size_t last_winner = 0;
   for( size_t blocks = 0; blocks < c_num_blocks; blocks++ )
   {
      long total_weight = 0;
      for( size_t i = 0; i < weights.size( ); i++ )
      {
         if( penalising[ i ] )
         {
            --penalising[ i ];
            weights[ i ] = 0;
         }
         else
         {
            int divisor = rand( ) % 10;

            if( divisor == 0 )
               ++divisor;

            weights[ i ] = ( rand( ) % 10000 ) * ( balances[ i ] / divisor );

            if( weights[ i ] == 0 )
               ++weights[ i ];

            total_weight += weights[ i ];
         }
      }

      if( total_weight == 0 )
         ++total_weight;

      size_t winner = 0;
      size_t runner_up = 0;
      long best_target = 0;
      long second_best_target = 0;

      for( size_t i = 0; i < balances.size( ); i++ )
      {
         long adjusted_weight = weights[ i ] * 1000 / total_weight;

         if( adjusted_weight > best_target )
         {
            winner = i;
            best_target = adjusted_weight;
         }
         else if( adjusted_weight > second_best_target )
         {
            runner_up = i;
            second_best_target = adjusted_weight;
         }
      }

#ifdef PENALISE_HIGHER_STAKE
      if( best_target == 350 ) // an above median value
      {
         ++penalised[ winner ];
         penalising[ winner ] = 1440;
      }
#endif

#ifdef PREVENT_IMMEDIATE_REPEAT
      if( winner == last_winner )
         winner = runner_up;
#endif

#ifdef SHOW_WINNERS
      winners += ( char )( 'a' + winner );
#  ifdef SHOW_WINNERS_WEIGHT
      ostringstream osstr;
      osstr << best_target;
      winners += "(" + osstr.str( ) + ")";
#  endif
#endif
      ++wins[ winner ];

      if( winner < balances.size( ) / c_combined_proportion )
      {
         ++combined_streak;
         if( combined_streak > best_combined_streak )
            best_combined_streak = combined_streak;
      }
      else
         combined_streak = 0;

      if( winner == last_winner )
      {
         ++streaks[ winner ];
         if( streaks[ winner ] > best_streak[ winner ] )
            best_streak[ winner ] = streaks[ winner ];
      }
      else
         streaks[ winner ] = 0;

      last_winner = winner;
   }

   cout << "blocks = " << c_num_blocks << endl;

   for( size_t i = 0; i < balances.size( ); i++ )
      cout << ( char )( 'a' + i ) << " = " << balances[ i ] << endl;

#ifdef SHOW_WINNERS
   cout << winners << endl;
#endif
   for( size_t i = 0; i < wins.size( ); i++ )
      cout << "wins( " << ( char )( 'a' + i ) << " ) = " << wins[ i ] << endl;

#ifdef PENALISE_HIGHER_STAKE
   for( size_t i = 0; i < penalised.size( ); i++ )
      cout << "penalised( " << ( char )( 'a' + i ) << " ) = " << penalised[ i ] << endl;
#endif

   for( size_t i = 0; i < best_streak.size( ); i++ )
      cout << "best_streak( " << ( char )( 'a' + i ) << " ) = " << ( best_streak[ i ] + 1 ) << endl;

   cout << "best_combined_streak = " << best_combined_streak << endl;
   cout << "(combined the first " << ( balances.size( ) / c_combined_proportion ) << " accounts)" << endl;
   cout << balances.size() << endl;
}


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TRUSTEE 
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Ian Knowles - CIYAM Lead Developer


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February 28, 2014, 09:02:08 AM
Last edit: February 28, 2014, 09:13:22 AM by CIYAM Open
 #38840

I edited the code and added a constant, c_combined_percent, to determine the proportion of accounts in collusion.  Assuming all nodes are limited to 1% forge power over a ten year period and a ninety percent collusion rate, I'm getting a combined best streak of 151, 137 and 136 from three runs.

That's really not too bad either - less than the time it takes to watch a LOTR film to be able to safely buy a house or other big investment even if 90% of the forging power is trying to secretly forge a replacement blockchain!

With CIYAM anyone can create 100% generated C++ web applications in literally minutes.

GPG Public Key | 1ciyam3htJit1feGa26p2wQ4aw6KFTejU
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