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WebDollar Blockchain

WebDollar Total Supply

100% equivalent to 42,000,000,000 WEBD

WebDollar Genesis Supply

9.8971455428571428571428571428571% equivalent to 4,156,801,128 WEBD

How to compute the genesis supply:

  • Genesis blocks are the first 41 blocks, starting from index 0 to index 40
  • For each block from the genesis, there is a reward value associated to it
  • Block 0 has reward 1 WEBD
  • Block 1 has reward 1,867,487,789 WEBD
  • Block 2 has reward 1,007,804,769 WEBD
  • ... Next blocks' values decrease according to a predefined discrete reward function
  • Block 39 has reward 6,306 WEBD
  • Block 40 has reward 6,113 WEBD

How to compute the genesis total supply with JavaScript:

 var FIRST_BLOCK_REWARDS = [1, 1867487789, 1007804769, 552321669, 307400655, 173745886, 99728963, 58133318,
  34413271, 20688253, 12630447, 7830882, 4930598, 3152722, 2047239, 1350046, 904119,
  614893, 424689, 297878, 212180, 153485, 112752, 84116, 63728, 49032, 38311, 30400,
  24497, 20047, 16660, 14061, 12051, 10490, 9272, 8323, 7588, 7025, 6604, 6306, 6113]

FIRST_BLOCK_REWARDS.reduce(function(a,b) {return a + b})
//$> 4156801128

WebDollar Block Reward

From block 0 to block 40, the rewards follow a discrete reward function and are presented above.
After block 40, the reward starts at 6000 and will halven each 3,153,600 blocks (genesis blocks included).

Example:

  • From block 40 to block 3,153,600, the reward is 6,000 WEBD.
  • From block 3,153,601 to block 6,307,200 the reward is 3,000 WEBD.

WebDollar Block Generation Time

Inter block generation time is set at 40 seconds.
The block generation difficulty compensates for the deviation.
The difficulty is recomputed every 10 blocks to allow for the mean 40 seconds window.

WebDollar Blockchain Persistence

The database of choice is PouchDB: (https://pouchdb.com).
The main reason behind it can be used both for server-side (nodejs) and web browsers.
PouchDB is API compatible with CouchDB (http://couchdb.apache.org).

WebDollar Block

We will use block 101247 as an example, which you can find it in the publicly available WebDollar blockchain.

Block 101247 serialized data in hex format:

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

Block 101247 data in JSON format:

{ id: 101247,
  block_id: 101247,
  hash: "000000010cbe65d1fb88cc8ad43804185a92cb3cb4414fa8aff77cc63ad01972",
  nonce: 1588855719,
  version: 1,
  previous_hash: "00000004efa42c9343b741ef481d5e74fd9276a960c47f96a81b1b877436c99a",
  timestamp: "Thu, 14 Jun 2018 20:13:00 GMT",
  hash_data: "eec15152d052fec11f361aa59d0a06e4dcc2e70d3aef07967dc7959a09710889",
  miner_address: "WEBD$gD5VX81cGcusj1I4aptf3ptshcCyCQ1drj$",
  trxs_hash_data: "5df6e0e2761359d30a8275058e299fcc0381534545f55cf43e41983f5d4c9456",
  trxs_number: 0,
  trxs: []
}

Now, how did we end up from the serialized data to the JSON format?
Brace yourself, the interesting part is coming :)

WebDollar Block Structure

|0|___32____|32|_____4____|36|_____2______|38|______32______|70|____4____|74|_____32_______|106|____20____|126|__32___|158|____4____|162|__??___|??|
 | BLOCK_HASH | BLOCK_NONCE | BLOCK_VERSION | BLOCK_PREV_HASH | BLOCK_TIME | BLOCK_DATA_HASH | MINER_ADDRESS| TRXS_HASH | TRXS_NUMBER | TRXS_DATA|
 |____________|_____________|_______________|_________________|____________|_________________|______________|___________|_____________|__________|

Now, let's apply this structure to the serialized hex format of block 101247:

[BLOCK_HASH]      000000010cbe65d1fb88cc8ad43804185a92cb3cb4414fa8aff77cc63ad01972
[BLOCK_NONCE]     5eb403a7
[BLOCK_VERSION]   0001
[BLOCK_PREV_HASH] 00000004efa42c9343b741ef481d5e74fd9276a960c47f96a81b1b877436c99a
[BLOCK_TIME]      004113a4
[BLOCK_DATA_HASH] eec15152d052fec11f361aa59d0a06e4dcc2e70d3aef07967dc7959a09710889
[MINER_ADDRESS]   f9557f3570672eb23d48e1aa6d7f7a6db21702c8
[TRXS_HASH]       5df6e0e2761359d30a8275058e299fcc0381534545f55cf43e41983f5d4c9456
[TRXS_NUMBER]     00000000
[TRXS_DATA]       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

!!! Notice that the block length is not constant, because of the transaction data which can differ from block to block.
Also, the transaction data is ignored in this scenario, as the transaction number is 0. But what if we have transactions in our block?

WebDollar Transaction Structure

We will use block 90010 as a transaction structure example, which you can find it in the publicly available WebDollar blockchain.
This block contains 2 transactions.

[BLOCK_HASH - TRXS_HASH] 0000000276784f0b40c0ab7d9f05020d233f665ef1c0ee75ce71851a04e6437f0000266d00010000000690780c947394d87f51635675c593e502ac73bbb15cb4de75d1150b390039e208bb16fca51d5a57b85bd5f59f6ce8c7ddcaa4db9971cb5f689c34a9ff8e43c047b526f062b0460108f11f4fcac97fa07ffe405d78441ee29395f49086dfeab481fc1d43d584443ef16142faa05d56062b47554005
[TRXS_NUMBER]            00000002
[TRXS_DATA]              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

We will be interested only in TRXS_DATA. As the block itself, the TRXS_DATA does not have a predefined length.

Transaction Structure before block 46950

|0|____1______|1|____1______|2|______3______|5|_____1____|6|__TRX_LENGTH x FROM_DATA_LENGTH_____|6+FROM_LENGTH|__1 ____|1 + PV|___CL____|CL + PV|____1__|1 + PV|____TRX_TO_LENGTH x TO_DATA_LENGTH __|TO_LENGTH + PV|
 | TRX_VERSION | TRX_NONCE   | TRX_TIME_LOCK | TRX_LENGTH |     FROM_DATA x TRX_LENGTH                 | CURRENCY_LENGTH  | CURRENCY_TOKEN | TRX_TO_LENGTH |        TO_DATA x TRX_TO_LENGTH                     |
 |_____________|_____________|_______________|____________|____________________________________________|_______CL_________|________________|_______________|____________________________________________________|
FROM_LENGTH = TRX_LENGTH x 123
TO_LENGTH = TRX_TO_LENGTH x 27
CL = CURRENCY_LENGTH
PV = PREVIOUS VALUE

Transaction Structure after block 46950

After block 46950, there was a hard fork which incremented the TRX_NONCE by 1.

|0|____1______|1|____2______|3|______3______|6|_____1____|7|__TRX_LENGTH x FROM_DATA_LENGTH_____|7+FROM_LENGTH|__1 ____|1 + PV|___CL____|CL + PV|____1__|1 + PV|____TRX_TO_LENGTH x TO_DATA_LENGTH __|TO_LENGTH + PV|
 | TRX_VERSION | TRX_NONCE   | TRX_TIME_LOCK | TRX_LENGTH |     FROM_DATA x TRX_LENGTH                 | CURRENCY_LENGTH  | CURRENCY_TOKEN | TRX_TO_LENGTH |        TO_DATA x TRX_TO_LENGTH                     |
 |_____________|_____________|_______________|____________|____________________________________________|_______CL_________|________________|_______________|____________________________________________________|

Transaction FROM Structure

|0|____20_____|20|_____32_____|52|_____64____|116|____7___|123|
 | FROM_ADDRESS | FROM_PUB_KEY | FROM_SIGNATURE| FROM_AMOUNT|
 |______________|______________|_______________|____________|

Transaction TO Structure

|0|____20____|20|____7__|27|
 | TO_ADDRESS | TO_AMOUNT |
 |____________|___________|

Transaction deserialization

Let's apply the transaction structure for the first transaction in block 90010:

[TRX_VERSION]     01
[TRX_NONCE]       0009
[TRX_TIME_LOCK]   015f98
[TRX_LENGTH]      01
[FROM_ADDRESS]    d0eb461b96d6c38f37da332b9871d0875be9b3b9
[FROM_PUB_KEY]    2c74b30324605841eaa3d3541b27239608b88a862a0b98cde8131e4334651899
[FROM_SIGNATURE]  739aa0c62876805d1663ec71fe3766f07626200c1e9f8ef7aeea82fcdb94809ff3263b715bcc05a4b427bd8049254bfdf20c242f072db54136c47d8a28976d0e
[FROM_AMOUNT]     a0453120000000
[CURRENCY_LENGTH] 01
[CURRENCY_TOKEN]  01

[TRX_TO_LENGTH]   01
[TO_ADDRESS]      c91896c3cb5dc6f158e2c739c2bf21fd6c44a18f
[TO_AMOUNT]       00bf2f20000000

Let's apply the transaction structure for the second transaction in block 90010:

[TRX_VERSION]     01
[TRX_NONCE]       0006
[TRX_TIME_LOCK]   015f98
[TRX_LENGTH]      01
[FROM_ADDRESS]    7ab213e9203f1578aca896b288ddfbba7a41782e
[FROM_PUB_KEY]    18499b93d12652ae173cc2510d6e6ba6448bb6fd29aac27cadc4e3a72033b439 
[FROM_SIGNATURE]  d461ac286ec33d8cc30d6cd445251b213d28e47192b2c7cc2a83d812bfa4d5c5ab6b6d75b123eed97d6bfba256ede016eb5d694c6ebb11a7dfceb46655582d0c
[FROM_AMOUNT]     a0b07615000000
[CURRENCY_LENGTH] 01
[CURRENCY_TOKEN]  01

[TRX_TO_LENGTH]   01
[TO_ADDRESS]      c91896c3cb5dc6f158e2c739c2bf21fd6c44a18f
[TO_AMOUNT]       002a7515000000

All fine and dandy, but what if TRX_LENGTH is not 1?

Block Structure for block 97124:

[RAW_HEX_BLOCK]   00000005ddcec101496dad8a8b76b6e255c883c58e0088884578e79791d9800301e630e4000100000004e56a6d6c2b36cee6c31866ff78a14837c03f6ed7944603edb5d49c3b003e74d76780a31320a13153d63513592bb44ee9b461bc14768daace35a3a211e18068e6ca13dc8f7c04fb12667fa09cb9a2d2406d9c617b305651fa48567cde0a885f05830e92d3f5853387b6681dc898e91c81c5feb98a00000002010003017b61037cd7616cecba2d5db1d0bd541b0c0c97547f53aa9350e355430f684aa51ad566277dcb7dd4b451d7d4a64c98ad31dd5f45a41606aa965e3b16a0622059ce526856cdd9e6e75c6306c6efb997e523ef5686ae43afb829caf9e5376a1cae9e897b8f9f12a0d81bce8f215a659730fcf2926c6e44078096980000000039e2f0b8ad272e36760c7016abca0727f7505a05c2a68700b86484071f363f75df4b21f57c0b4e5d2e39087fd5c8fa522708f73530e9bedc2c0066396af48b93344755c9fa49bff8d7bd01a9cc16b6895d7a0b3e9e7b29ff6eb2406a967d007beda84070e2fc2b3f44b494e174236d5493ddc70a8096980000000058daddad25b11cd1fd0ba1e03c4a7717f8fe606cd1abcd904c9d29a551cc4e069043f557b54d314f5128e86bc88ee85b29ed8437b17f5aa5e710ef20a3b40cf631d6e32a9d55883888e08a318976a2285687916192f02176f07e96b4d2835b5a27b41989cbcdaba9f674bdbcef2db01b183db50d80969800000000010102f4a260b258ad2df767e04e99a880492baa7a966de00f9700000000a25c064a7a0633dee8b6330bce4c8a55d4700e7bc01f2e01000000010001017b62014519ca1ee719b2f713ffe1f8fcb3685c992a300253a4a1a4e9814d6d7963404a476cd159376523c58e6adfc6a31ca94ba3e73231b72aa9e2e45a21bbaa7d9d6fd4a68e12931cd3a1bd26374b5c9dcced0a6bfbdd19252d5bdd75086d756ae51688bc151d2b31b8a94cc7e3842c1bb487a8be380a008793030000000101011d979ff277916faba0069f0b30d9c773d8e829446000920300000046296f256e0bb9546c29483bec83654716c5b80be15718dc37eedb9d4c32c2cb14000001731d46c131eb6dd4667a96bdc27baf9223bec72c3468dfb6ba52c460e76423a4017b6400000002c8901f310ec0a064b7033d6fadee01bef57f3d69c83c791d37100bdc017b6200000001878c3b6a145c67824ff351ea0c472e21f0031a609c604d43ada7033f017b60000000001ecdc68beedc75af50be13d079af9b78acd90a37430c362f9420ed120000000000000000000179610000000007431c4455d845eef550d77ffd57f38a3ec1bd39c1e2d8c8c06682a901775300000000044ae0bbd125bb97ea6c91dcd8fbb21dae021e7e0224deb8c3127f720176bf00000000007624e96f4824a2f0ddf419292767eef53b035263172065225794b2000000000000017684000000000014636ffd74d9bb7b386147b35d3d8c89fc685360da105f9fdb716b000000014bd7000000000025ef1ed3c39ee8ef75733015d2a0be830a09819675bf6b93a0f7440146db000000000000a73a76d6bfa88f1fe4586194cf4ad657bb0229e3ec4a40138dcd000000000000000000000000
[BLOCK_HASH]      00000005ddcec101496dad8a8b76b6e255c883c58e0088884578e79791d98003
[BLOCK_NONCE]     01e630e4
[BLOCK_VERSION]   0001
[BLOCK_PREV_HASH] 00000004e56a6d6c2b36cee6c31866ff78a14837c03f6ed7944603edb5d49c3b
[BLOCK_TIME]      003e74d7
[BLOCK_DATA_HASH] 6780a31320a13153d63513592bb44ee9b461bc14768daace35a3a211e18068e6
[MINER_ADDRESS]   ca13dc8f7c04fb12667fa09cb9a2d2406d9c617b
[TRXS_HASH]       305651fa48567cde0a885f05830e92d3f5853387b6681dc898e91c81c5feb98a
[TRXS_NUMBER]     00000002
[TRXS_DATA]       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

First transaction for block 97124:

[TRX_VERSION]     01
[TRX_NONCE]       0003
[TRX_TIME_LOCK]   017b61
[TRX_LENGTH]      03

[FROM_ADDRESS_1]    7cd7616cecba2d5db1d0bd541b0c0c97547f53aa
[FROM_PUB_KEY_1]    9350e355430f684aa51ad566277dcb7dd4b451d7d4a64c98ad31dd5f45a41606 
[FROM_SIGNATURE_1]  aa965e3b16a0622059ce526856cdd9e6e75c6306c6efb997e523ef5686ae43afb829caf9e5376a1cae9e897b8f9f12a0d81bce8f215a659730fcf2926c6e4407
[FROM_AMOUNT_1]     80969800000000

[FROM_ADDRESS_2]    39e2f0b8ad272e36760c7016abca0727f7505a05
[FROM_PUB_KEY_2]    c2a68700b86484071f363f75df4b21f57c0b4e5d2e39087fd5c8fa522708f735 
[FROM_SIGNATURE_2]  30e9bedc2c0066396af48b93344755c9fa49bff8d7bd01a9cc16b6895d7a0b3e9e7b29ff6eb2406a967d007beda84070e2fc2b3f44b494e174236d5493ddc70a
[FROM_AMOUNT_2]     80969800000000

[FROM_ADDRESS_3]    58daddad25b11cd1fd0ba1e03c4a7717f8fe606c
[FROM_PUB_KEY_3]    d1abcd904c9d29a551cc4e069043f557b54d314f5128e86bc88ee85b29ed8437 
[FROM_SIGNATURE_3]  b17f5aa5e710ef20a3b40cf631d6e32a9d55883888e08a318976a2285687916192f02176f07e96b4d2835b5a27b41989cbcdaba9f674bdbcef2db01b183db50d
[FROM_AMOUNT_3]     80969800000000

[CURRENCY_LENGTH] 01
[CURRENCY_TOKEN]  01

[TRX_TO_LENGTH]   02

[TO_ADDRESS_1]      f4a260b258ad2df767e04e99a880492baa7a966d
[TO_AMOUNT_1]       e00f9700000000

[TO_ADDRESS_2]      a25c064a7a0633dee8b6330bce4c8a55d4700e7b
[TO_AMOUNT_2]       c01f2e01000000

Transaction amount pooling

As seen in the first transaction of block 97124, a transaction can have x senders and y receivers, where x != 0 and y != 0.
The senders amounts are sumed up and the receivers receive from that collective amount.
The fee is the difference between the sum of the senders amount and the sum of the receivers amounts.