Antara Customizations

The Antara Framework offers various default Antara Customizations.

The desired combination of parameters should be included with the komodod execution every time the Smart Chain daemon is launched.

Changing these customizations at a later time is possible, but this typically requires a hard-fork of your Smart Chain. In general, the best practice for a developer is have all Smart Chain's parameters finalized before decentralizing the ownership of your coin. Should you discover a need to change these parameters after the fact, please reach out to our development team for assistance.

ac_adaptivepow

Understanding Difficulty Stranding

The ac_adaptivepow parameter solves a vulnerability known as "Difficulty Stranding." Low-hashrate blockchains are particularly susceptible to this vulnerability.

When a blockchain's hashrate is much lower than that of another blockchain with the same mining algorithm, miners from the higher-powered chain can move to the lower-powered chain and mine a large number of blocks in a short amount of time.

In so doing, the rapid influx of new miners causes a part of the lower-powered chain's consensus mechanism called the Difficulty Adjustment Algorithm (DAA) to drastically increase the difficulty of finding a block. When the higher-powered group of miners leave, the difficulty level remains.

The smaller group of miners now may not be able to provide enough hash power to overcome the new difficulty level, and therefore this chain can be frozen.

This type of behavior is called "difficulty stranding,” and can be used as a method of malicious attack. This is a threat that is faced by all pure PoW chains that have a minor hashrate.

ac_adaptivepow Adjusts the Difficulty Level

The ac_adaptivepow parameter changes the Difficulty Adjustment Algorithm (DAA) of a Smart Chain to alleviate the potential effects of a "difficulty stranding" attack.

One method by which ac_adaptivepow alleviates the vulnerability is the changing of the time at which the difficulty level is set. Normally, the difficulty level is adjusted at the conclusion of finding a new block. With ac_adaptivepow, the difficulty target is adjusted as a part of the process of finding a new block.

This makes the process of lowering the difficulty easier and faster, as the DAA can take into account the amount of time the miners on the network are consuming to find a new block. If the amount of time is too high, the DAA can lower the difficulty as needed. More details on the implementation and rationale can be found in this blog post.

Adding the parameter -ac_adaptivepow=1 enables AdaptivePoW for a newly created Smart Chain.

ac_algo

The ac_algo parameter changes the chain's mining algorithm from the default equihash to the verushash.

To enable this feature, set -ac_algo=verushash.

This activates verushash1.0. More recent versions of verushash are not yet supported.

The verushash feature serves as a proof of concept for adding support for additional mining algorithms.

The Komodo team is currently testing methods to support compatibility for ac_staked, but this feature is not yet recommended for external testing.

ac_blocktime

This parameter sets the average time (in seconds) by which a new block should be mined.

If this parameter is not included, the default value is ac_blocktime=60.

When the value of ac_blocktime is less than 60, the Smart Chain's block time will stabilize within less than twelve hours after launch. If the Smart Chain's ac_blocktime value is greater than 60, the Smart Chain's block time can require several days to stabilize.

When the value of ac_blocktime is less than 12 seconds (a high speed Smart Chain), the variances in network quality between consensus nodes (miners and stakers) can create difficulties in achieving a stable blockchain consensus. High-speed Smart Chains may function effectively on a LAN or other stable network, but Komodo recommends caution when attempting to manage a high-speed Smart Chain on the public Internet.

📌 Examples

ac_cbmaturity

The ac_cbmaturity parameter allows the COINBASE_MATURITY value to be changed.

The COINBASE_MATURITY value is the number of blocks that must be confirmed between the creation of a coin (in a coinbase transaction) and the moment the coin can be spent.

This allows the developers of a Smart Chain to require that miners and stakers on a blockchain network wait for an arbitrary amount of time after mining new coins to spend them..

For example, if a Smart Chain is set to ac_cbmaturity=10, newly mined coins must wait for 10 confirmations on the network before they can be spent.

By default, this value is set to 1 on Smart Chains without ac_eras and set to 100 on Smart Chains with ac_eras.

ac_cbopret

(In Development)

The ac_cbopret parameter allows the Decentralised Trustless Oracle mechanism to be enabled on a Smart Chain.

The value of the parameter is a 4 bit binary number converted to decimal. Each bit of the binary number has a specific meaning as explained below:

Let the 4 bit binary number be wxyz

w,x,y,z are bit4, bit3, bit2 and bit1 respectively

• if z = 1 : DTO is enabled and miners are required to add some data to the coinbase transaction's OP_RETURN
• if y = 1 : the data miners will write is prices of BTC vs fiat pairs viz., BTC_USD, BTC_GBP, BTC_EUR and Major fiat vs USD pairs
• if x = 1 : the data miners will write is prices of Cryptocurrencies included in the -ac_prices parameter
• if w = 1 : the data miners will write is prices of Stocks included in the -ac_stocks parameter

Examples

• If we only want the prices for BTC vs fiat pairs and fiat vs USD pairs, we have (w=0,x=0,y=1,z=1) i.e., 0011 -> converted to decimal is 3; the value for the ac_cbopret parameter is 3
• If we want the pairs from the above example and prices of the Cryptocurrencies included in the -ac_prices parameter, we have (w=0,x=1,y=1,z=1) i.e., 0111 -> converted to decimal is 7; the value for the ac_cbopret parameter is 7
• If we just want the prices of the Stocks included in the -ac_stocks parameter, we have (w=1,x=0,y=0,z=1) i.e., 1001 -> converted to decimal is 9; the value for the ac_cbopret parameter is 9

ac_cc

The ac_cc parameter sets the network cluster on which the chain can interact with other chains via Antara modules and MoMoM technology.

Once activated, the ac_cc parameter can allow features such as cross-chain fungibility -- coins on one Smart Chain can be directly transferred to any other Smart Chain that has the same ac_cc setting and the same set of notary nodes (same set of notary pubkeys) .

Most functionalities enabled by ac_cc can function with or without Komodo's notarization service. However, cross-chain transaction validation and its dependent features, including cross-chain fungibility, require notarization.

If the ac_cc parameter is set to a value greater than 0 (i.e. Antara is permitted on the Smart Chain) users should include the -pubkey parameter when launching the daemon of this Smart Chain.

ac_cc=0

Setting ac_cc=0 disables Antara on the Smart Chain entirely.

ac_cc=1

Setting ac_cc=1 permits Antara on the Smart Chain, but will not allow the Smart Chain to interact in cross-chain Antara functionality with other Smart Chains.

ac_cc=2 to 99

The values of 2 through 99 (inclusive) indicate Smart Chains that can validate transactions that occur on other Smart Chains on the same cluster (i.e. the same ac_cc value), but their coins are not fungible and therefore cannot be transferred between blockchains.

ac_cc=100 to 9999

Setting the value of ac_cc to any value greater than or equal to 100 will permit cross-chain interaction with any Smart Chain that has the same ac_cc value and is secured by notary nodes with the same pubkey.

All Smart Chains that have the same ac_cc (>= 100) value form a cluster, where the base tokens of all the chains in the cluster are fungible via the burn protocol.

For example, a Smart Chain set to ac_cc=201 in its parameters can interact with other Smart Chains with ac_cc=201 on the same notary-node network, but cannot interact with a Smart Chain set to ac_cc=301.

Summary of ac_cc

📌 Examples

ac_ccactivate

-ac_ccactivate=block_height

The ac_ccactivate launch parameter allows for the activation of Antara on an existing Komodo-based Smart Chain wherein Antara was not originally enabled.

Add the ac_ccactivate parameter to the existing launch command for the Smart Chain and set the value equal to a future block height. When this block height is reached, Antara will be available on the Smart Chain.

This change requires a hard fork of the Smart Chain. If the Smart Chain is receiving Komodo's dPoW security service, the notary nodes must relaunch their Smart Chain daemons with the new launch parameter. All nodes must also update their daemons in the same manner.

By default, ac_ccactivate uses the default ac_cc value of ac_cc=2. It is not necessary to further specify ac_cc in the launch parameters, unless a value other than 2 is required.

📌 Examples

ac_ccenable

The ac_ccenable parameter restricts the Smart Chain so that only indicated Antara modules can be enabled. ac_ccenable requires ac_cc to be active.

To indicate which Antara modules should be available, insert each module's eval code in decimal and separated by commas.

The following table presents an abbreviated list of EVAL codes. For more information, please see this linked content.

For example, the following parameters create a Smart Chain where only the faucet and rewards modules are active:

./komodod -ac_name=EXAMPLE -ac_supply=0 -ac_reward=100000000 -ac_cc=2 -ac_ccenable=228,229

When -ac_cc is set, but -ac_ccenable is not, all Antara modules are enabled.

ac_cclib

The ac_cclib parameter is used in conjunction with various Antara modules.

Typically, the Smart Chain that uses the ac_cclib parameter will have a unique build process. This is described as a part of each Antara module in question. Once the Smart Chain is properly built, the terminal command to launch the chain will include the ac_cclib parameter in a manner similar to the following:

-ac_cclib=desired_CC_module

Each Antara module uses the ac_cclib parameter differently, and therefore the reader should refer to the desired Antara module for further instructions.

ac_decay

This is the percentage which determines the block reward decrease on each block-reward "halving".

This parameter will have no effect if ac_reward is not set.

This is the formula that ac_decay follows:

block_reward_after = block_reward_before * ac_decay / 100000000;

For example, if this parameter is set to 75000000, at each "halving" the block reward will drop to 75% of its previous value.

📌 Examples

ac_end

This is the block height at which block rewards will end. Every block after this height will have 0 block reward (this means that, assuming all other settings are default, the only incentive to mine a new block will be transaction fees).

📌 Examples

ac_eras

The ac_eras parameter allows the value of a chain's block reward to vary over time.

Each different time interval is called an "era" and a chain can have at most seven eras.

ac_eras Combined With ac_cbmaturity

When active, ac_eras changes the behavior of coinbase coins (i.e., the coins that are created as a result of mining). ac_eras forces the COINBASE_MATURITY value of coinbase coins to be 100 instead of the normal value of 1. Therefore, coinbase coins become spendable after 100 confirmations.

This COINBASE_MATURITY value can be explicitly changed using the ac_cbmaturity parameter. Changing this COINBASE_MATURITY value to 1 is recommended if a chain uses ac_eras in conjunction with ac_staked.

ac_eras Instructions

The ac_eras parameter accepts only one value. The value must be between 2 and 7, inclusive. When activated, ac_eras allows certain other Smart Chain parameters to accept multiple values.

The principle parameter that is affected by ac_eras is ac_reward. The ac_reward parameter must receive at least one value.

Also, ac_decay, ac_halving, ac_end, and ac_notarypay can each receive multiple values and thereby affect reward functionality.

For every era, there must be a corresponding value in ac_end that indicates the block height at which this era ends. To set the final era to last indefinitely, set the ac_end value of that era to 0; the 0 setting should only be used for the last era. If the last era's ac_end value is not 0, the chain's block rewards will stop after the final ac_end value, and every block after the final ac_end value will have no block reward.

In all parameters receiving multiple values, the values must be preceded by a comma.

For example:

./komodod -ac_name=HELLOWORLD -ac_supply=777777 -ac_eras=3 -ac_reward=5000000000,7000000000,4000000000 -ac_end=1000,10000,0

In this Smart Chain, the first era will have a reward of 5000000000, the second will have 7000000000, and the third will have 4000000000. The reward for the first era ends at block 1000, for the second era at block 10000, and the third era lasts indefinitely.

If any of the relevant parameters has fewer distinct values than eras, the parameter's final value will carry through the remaining eras.

For example:

-ac_eras=2 -ac_reward=100000000,200000000 -ac_halving=100 -ac_end=10000,0

In this Smart Chain, the ac_halving value for both eras is 100.

One more feature of ac_eras is the ability to transition from one era to the next with a linear progression, rather than a direct switch. To achieve this effect, in the initial era (the point at which the linear progression should begin) set the ac_decay value to 100000000 and the ac_halving value to 1.

For example, the following parameters create a Smart Chain with a "slow start" reward:

./komodod -ac_name=HELLOWORLD -ac_reward=0,10000000000 -ac_eras=2 -ac_end=1000,0 -ac_decay=100000000,100000000 -ac_halving=1

This chain's block reward will grow linearly from 0 to 100 over 1000 blocks, then stay at 100 indefinitely.

ac_feeds

The ac_feeds parameter supports the retrieval of data from sources accessed using the http/https protocols and which return data as a json object.

The Antara Prices Module has an internal parser that processes the json object using the RFC 6901 'Json Pointer' addressing. The internal parser extracts the value specified by the json pointer or calculates the average value for the specified value paths, as explained below.

This parameter also allows the addition of a custom shared object library (a .so file) that has the necessary parsing function to retrieve values from the json object returned by a web api. This feature can be used when the json object returned is non-standard and the internal parser's features are not sufficient. In this event, the parsing function takes the json object and several configuration options, such as customdata, as arguments and returns the price. The configuration options inform the function about the location of the price data within the json object.

The value of this parameter is a quoted string that contains a json array of feed-configuration options.

Basic Usage

-ac_feeds='[{"name":"stocks", "url":"https://api.iextrading.com/1.0/tops/last?symbols=AAPL,ADBE", "results":[{"symbol":"AAPL","valuepath":"/0/price"}, {"symbol":"ADBE","valuepath":"/1/price"}], "multiplier":1000000, "interval":120 }, {configuration object for another feed ...}]'

Each json object in the above json array defines a unique Feed. The json array includes details such as the Feed's name, the web api's url, the symbol for each of the items in the feed, and the path to acquire the price data for an item from the json returned from the web api.

ac_feeds Example

{
  "name": "stocks",
  "url": "https://api.iextrading.com/1.0/tops/last?symbols=AAPL,ADBE",
  "results": [
    { "symbol": "AAPL", "valuepath": "/0/price" },
    { "symbol": "ADBE", "valuepath": "/1/price" }
  ],
  "multiplier": 1000000,
  "interval": 120
}

The above configuration object defines a single feed named "stocks" that contains prices of the symbols AAPL and ADBE retreived from the web api with the "url": https://api.iextrading.com/1.0/tops/last?symbols=AAPL,ADBE.

The returned data is a json array and is processed by ac_feeds's internal parser to set the prices of the symbols AAPL and ADBE based on the data in the json array. This data is found in the results key.

{ "symbol": "AAPL", "valuepath": "/0/price" }

The value of the key named symbol sets the symbol for the item in the price feed.

The value of the key named valuepath is a json "pointer" that indicates the method to extract the value of the price matching the symbol in the response. For example, when the parser encounters the value "/0/price", the parser selects the 0th element of the json array and reads the value of the key named price.

The value of the key named multiplier is the number by which the value extracted should be multiplied before being added to the feed. This convers numbers with decimal paces into integers.

The value of the key named interval is the time in seconds between each refresh of the data from the web api. The minimum value is 120.

Polling the Same url Multiple Times

The following example can be useful when polling the same url multiple times with a fixed subset of changing.

-ac_feeds='[{"name":"metals", "url":"https://forex-data-feed.swissquote.com/public-quotes/bboquotes/instrument/%s/USD", "substitutes":["XAU","XPT"], "quote":"USD", "results":{"averagevaluepaths":["/*/spreadProfilePrices/*/ask","/*/spreadProfilePrices/*/bid"] }, "multiplier":10000, "interval":120 }]'

The above example has the configuration for a single feed named "metals" that allows for the retrieval of the prices XAU/USD (XAU_USD) and XPT/USD (XPT_USD) symbols from the web api hosted by forex-data-feed.swissquote.com.

The key url has the actual address of the web api, with %s included to denote "substitute". All the urls formed by the substitution %s and with elements of the array stored in the key named substitues are polled. Their responses are processed and added to the feed. As before, the key named "results" holds the data that indicates the method for processing the responses.

{
  "averagevaluepaths": [
    "/*/spreadProfilePrices/*/ask",
    "/*/spreadProfilePrices/*/bid"
  ]
}

In this case, the results object indicates that the price value to be added to the feed is the average of all values retrived from the responses based on the json pointers "/*/spreadProfilePrices/*/ask" and "/*/spreadProfilePrices/*/bid".

Note the '*' symbols in the json pointers. These indicate that the response is an array and all the elements of the array will be used in the calculation of the average. When the key substitutes is used in the configuration, the result parameter is a json object and is applied to the resulting json response from polling each url formed by using each substitute.

There is also an optional parameter named quote which is added to the symbol of the price in the feed. For example, using the values "quote":"USD" displays the prices as XAU_USD and XPT_USD in the feed. The quote value can also be empty if the strings in the array substitutes are complete symbols.

Method of Handling when the Internal Parser is Inadequate

When the internal parser of the ac_feeds customization is inadequate for parsing responses from a web API, the following example can be of assistance.

-ac_feeds='[{"name":"metals", "url":"https://forex-data-feed.swissquote.com/public-quotes/bboquotes/instrument/%s/USD", "substitutes":["XAU","XPT"], "quote":"USD", "customlib":"libpricessampleparser.so", "results":{"customdata":"/0/spreadProfilePrices/0/ask"}, "multiplier":10000, "interval":120 }]'

This feed configuration has a custom parser.

The feed is differentiated from the previous feed by the customlib key, which contains the name of a shared library that contains the custom parser, and the customdata key, which is arbitraty data passed to the custom parser function in the shared library.

-ac_feed Parameters

Results Array Members

Results Object Members

Specification for the Custom Parser Library

The custom json parser is a shared library that should be placed along with the Komodo source code with building instructions in the src/cc/priceslibs directory.

The custom library should implement a single function written in the C-language with its declaration specified in the file pricesfeeds.h as follows:

extern "C" {
    int pricesJsonParser(const char *sjson /*in*/, const char *symbol /*in*/, const char *customdata, uint32_t multiplier /*in*/, uint32_t *value /*out*/);
}

On each call, the function should retrieve a single value and place it in the '*value' variable.

The function receives the following parameters:

• A string with the json returned by web api
• The symbol to retrieve
• Custom data from the configuration
  • The custom data might contain hints on how to find the value in the json object
• A multiplier used to convert the price value to integer

The function should return 1 for the success scenario and 0 if the function could not extract the value.

For an example implementation, see the custom parser lib example in the file named PricesResultParserSample.cpp in the directory src/cc/priceslibs in the Komodo source code.

Initializing Price Feed Configuration

The configuration object is named feedconfig and is found in the file src/cc/pricesfeeds.cpp.

Use an existing configuration (config) item with name="basic" as an example.

ac_founders

The ac_founders parameter creates a "founder's reward."

This parameter requires ac_perc. If the ac_perc value is not declared, the ac_founders value defaults to 35%. Also, either ac_pubkey OR ac_script must be set.

The ac_perc value determines the percentage of block rewards paid to the founder. These rewards are not paid out immediately, but rather according to the ac_founders setting.

ac_founders determines the frequency at which the founder's reward is paid.

For example:

-ac_reward=100000000 -ac_perc=10000000 -ac_founders=100

The above parameters result in mining rewards of 100000000 satoshis (1 coin) per block, with a difference on every 100th block. On the 100th block exception, 1000000000 additional satoshis (10 coins) are paid to the founder's address.

The coins rewarded to the founder are created at the moment of payment, thus increasing the overall coin supply. See ac_perc for more details.

Use ac_pubkey to send the founder's reward to a normal address.

Use ac_script to send the founder's reward to a multi-signature address.

Set ac_founders=1 to stay compatible with most stratum implementations. Any other value requires team member Blackjok3r's modifications to knomp using the disable-cb feature. Please reach out to our team on discord if you have further questions about how to set up a stratum.

ac_founders_reward

The ac_founders_reward parameter functions in a manner that is similar to a combination of the ac_perc and ac_founders parameters.

However, the value specified in the ac_founders_reward parameter is given in satoshis, as opposed to a percentage of the block reward. Also, the founder's reward does not accumulate over several blocks.

The ac_founders_reward parameter can be used in place of ac_perc.

The ac_founders_reward parameter must be used in combation with ac_founders and either ac_script or ac_pubkey.

The ac_founders_rewards value is entirely independent of the ac_reward value.

Consider the following combination of parameters, for example.

-ac_reward=1000000000 -ac_perc=10000000 -ac_founders=10 -ac_pubkey=034916536402c0c4cf53b05e3b5d948aacafede47df640b33cb89bd28179cd2d3f

This combination pays the pubkey address 10 coins every 10 blocks.

Compare the above to the following combination.

ac_reward=1000000000 -ac_founders_reward=100000000 -ac_founders=10 -ac_pubkey=034916536402c0c4cf53b05e3b5d948aacafede47df640b33cb89bd28179cd2d3f

This combination pays the pubkey address 1 coin every 10 blocks.

The ac_founders_reward parameter is not compatible with the ac_eras parameter.

📌 Examples

ac_halving

This is the number of blocks between each block reward halving. This parameter will have no effect if ac_reward is not set. The lowest possible value is 1440 (~1 day). If this parameter is set, but ac_decay is not, the reward will decrease by 50% each halving.

📌 Examples

ac_name

This is the ticker symbol for the coin you wish to create. We recommended it consist only of numbers and uppercase letters.

📌 Examples

ac_notarypay

The ac_notarypay parameter rewards the notary nodes each time they participate in a notarization.

This value should be set to the total amount of satoshis rewarded to all participating notaries in a notarization. The reward is then divided evenly between all participating notaries.

On the KMD dPoW network the amount of notaries in a notarization is 13. Therefore, if the ac_notarypay value is set to 1300000000, each notary receives 1 coin for each notarization they perform.

Notarizations happen on average every 10 blocks by default.

This parameter is compatible with the ac_eras parameter.

📌 Examples

ac_perc

The ac_perc parameter has two different functionalities depending on the configuration of the chain parameters.

ac_perc without ac_founders

When ac_perc is used without -ac_founders the chain will follow an inflation-tax model. In this model, the -ac_perc parameter is the percentage added to the block reward, and the transactions that allocate these rewards are sent to the -ac_pubkey address. Naturally, for this configuration to function the -ac_pubkey parameter must be included.

For example, if -ac_reward=100000000 and -ac_perc=10000000, for each block mined the miner receives 100000000 satoshis (1 coin), and the owner of the -ac_pubkey address receives 10000000 satoshis (0.1 coin, which is 10% of the miner's reward). The amount sent to the pubkey is not taken from the user, rather it is created at this point. Therefore, each transaction inflates the overall coin supply.

The maximum amount of coins created via this method across all transactions per block is capped at (1000000 * <percentage>).

ac_perc with ac_founders

Please see the -ac_founders documentation for this functionality.

📌 Examples

ac_prices

(In Development)

The ac_prices parameter has to be used along with the ac_cbopret parameter to supply TICKERS of the Cryptocurrencies whose BTC prices are to be included in the DTO.

📌 Examples

ac_pubkey

The ac_pubkey parameter designates a pubkey for receiving payments from the network. These payments can come in the genesis block, in all blocks mined thereafter, and from every transaction on the network.

This parameter is not intended for isolated use. It should only be activated on chains that also use at least one of the following parameters: ac_perc, ac_founders, or ac_import=PUBKEY.

The pubkey must be a 66 character string (a compressed pubkey). You can find this pubkey for any address by using the validateaddress command, and searching for the returned pubkey property. The first two digits of a compressed pubkey are only either 02 or 03. (The corresponding private key must be present/imported to the wallet before using validateaddress.)

📌 Examples

ac_public

If ac_public is set to 1, zk-SNARKs are disabled, and all z address functionality is disabled. Therefore, all transactions on the blockchain are public.

📌 Examples

ac_reward

This is the block reward for each mined block, given in satoshis.

If both ac_reward and ac_staked are not set, the default block reward will be 10000 satoshis and blocks will be on-demand after block 127 (a new block will not be mined unless there is a transaction in the mempool).

Komodo recommends that ac_reward be included in all Smart Chains. This prevents the Smart Chain from becoming an on-demand blockchain, and therefore this increases the Smart Chain's security.

To make a Smart Chain that has no block reward and is not on-demand, include the parameters: -ac_reward=1 -ac_end=1. The Smart Chain's first block will reward only the -ac_supply value, after which the ac_reward value will be 0.

📌 Examples

ac_sapling

The ac_sapling parameter adjusts the block height of a Smart Chain's default sapling activation. (Sapling is an upstream privacy technology provided by Zcash, of which Komodo is a fork.)

By default, sapling will activate at block 61 on a newly created Smart Chain.

This can also be used to activate sapling prior to block 61. (Activating sapling prior to block 61 should not be done on a chain intended for production use.)

To delay sapling activation, set ac_sapling to a block height far in the future. For example, -ac_sapling=5000000 will delay sapling activation to block 5000000. At block 5000000 sapling will be activated.

To support private transactions from the beginning, new AC chains must include the -ac_sapling=1 parameter, otherwise these chains will not be able to send shielded transactions until sapling activation, as old Sprout proofs are no longer supported. Additionally, all Sprout transactions have been prohibited since February 15, 2019 by consensus rules.

ac_script

The ac_script parameter enables the ac_founders reward to be sent to a multi-signature address or any p2sh address. If this parameter is used, block 1 (the "premine") will be mined to the ac_script address.

This parameter requires that ac_founders also be active. If ac_script is set, ac_pubkey must not be.

ac_script should be set to the "hex" value of "scriptPubKey".

Finding the scriptPubKey

To find the "scriptPubKey" value, first create a multi-signature address with the createmultisig command.

Command

./komodo-cli -ac_name=EXAMPLE createmultisig 2 "[\"RMnZJpfLbFHUxMS3HM5gkvtFKeduhr96Ec\",\"RW2Yx4Tk9WGfUvhbJTXGFiRhr7PKcVtrm5\",\"RQ1uqBj9yk94BcxEZodbeNqb3jWv8pLeA4\"]"

Response

{
  "address": "bGHcUFb7KsVbSFiwcBxRufkFiSuhqTnAaV",
  "redeemScript": "522102040ce30d52ff1faae7a673c2994ed0a2c4115a40fa220ce055d9b85e8f9311ef2102a2ba4606206c032914dd48390c15f5bf996d91bf9dbd07614d972f39d93a511321026014ef4194f6c7406a475a605d6a393ae2d7a2b12a6964587299bae84172fff053ae"
}

On a test chain, send coins to the bGHcUFb7KsVbSFiwcBxRufkFiSuhqTnAaV address.

Command

./komodo-cli -ac_name=EXAMPLE sendtoaddress bGHcUFb7KsVbSFiwcBxRufkFiSuhqTnAaV 10

Response (txid)

ef0d05f14ea2a5bfa1c99142c2e3d78c851223d7476ed2e57b61b6e07f741f0f

Observe the resulting transaction with getrawtransaction <txid> 1.

Command

./komodo-cli -ac_name=EXAMPLE getrawtransaction ef0d05f14ea2a5bfa1c99142c2e3d78c851223d7476ed2e57b61b6e07f741f0f 1

Response

{
  "value": 10.0,
  "valueSat": 1000000000,
  "n": 1,
  "scriptPubKey": {
    "asm": "OP_HASH160 2706324daaac92c93420e985f55d88ea20e22ae1 OP_EQUAL",
    "hex": "a9142706324daaac92c93420e985f55d88ea20e22ae187",
    "reqSigs": 1,
    "type": "scripthash",
    "addresses": ["bGHcUFb7KsVbSFiwcBxRufkFiSuhqTnAaV"]
  }
}

Set ac_script to the "hex" value from the returned json object.

Command

-ac_script=a9142706324daaac92c93420e985f55d88ea20e22ae187

ac_staked

ac_staked indicates the percentage of blocks the chain will aim to mine via Proof of Stake (PoS), with the remainder via Proof of Work (PoW). For example, an ac_staked=90 chain will have ~90% PoS blocks and ~10% PoW blocks.

Measurements of the PoS:PoW ratio are approximate; the PoW difficulty will automatically adjust based on the overall percentage of PoW-mined blocks to adhere to the approximate PoS value.

When creating a chain with the ac_staked parameter, the creation process is slightly different.

• Start both the first and second nodes without -gen -genproclimit=0.
• Once both are connected, execute setgenerate true 1 on the node that should receive the pre-mine.
• Observe the debug.log by executing tail -f ~/.komodo/<CHAIN>/debug.log
• Wait for the Smart Chain to mine two blocks
• Execute setgenerate false to stop mining
• All of the coins (including the pre-mine) are now located on the node that mined two blocks. Do not split them with a normal transaction. Rather, split them using this tool: link.
• On the first node use 'setgenerate true 0' to enable staking.
• On the second node use 'setgenerate true 1' (or use a desired processor number instead '1') to enable mining.
• Use the getbalance64 method to ensure that there are coins staking in all 64 segids before block 10. The utxos may appear on any list, including both staking and nonstaking.

Following the above instructions will ensure that the Smart Chain is stable.

Notes on How ac_staked Functions

Once staking is active, utxos available in the wallet.dat file will stake automatically.

On an ac_staked Smart Chain there are 64 global segments (segid's) to which all addresses and the corresponding utxos belong. These 64 segid's become eligible to stake blocks in turns. The segment a utxo belongs to is determined automatically, according to the address in which the utxo resides.

You can see which segment an address belongs to by using the validateaddress API command. You can use the getbalance64 API command to observe how your staked coins are distributed across the separate segids.

Each staked block will have an additional transaction added to the end of the block in which the coins that staked the block are sent back to the same address. This is used to verify which coins staked the block, and this allows for compatibility with existing Komodo infrastructure.

There are additional considerations when ac_staked is used in conjunction with ac_perc and ac_pubkey. The coins used to stake will be included in the ac_perc calculations until the Smart Chain reaches block height 1000000. Therefore, the ac_pubkey address will receive more coins for each staked block compared to a mined block. After block 1000000, ac_perc will no longer include the coins used for staking, and therefore the amount of coins sent to the ac_pubkey address will normalize.

Rules for Staking a Block

The following are the (current) rules for staking a block:

• Block timestamps are used as the monotonically increasing on-chain clock. It is important to have a synced system clock. Use the following sequence to sync your clock:sudo apt-get install chrony, sudo systemctl restart chrony.service, then check timedatectl for NTP syncronized: Yes

• A utxo is not eligible for staking until a certain amount of time has passed after its creation. By default, between blocks 1 and 2000 the amount of time required for a utxo to be eligibile is blockheight * 3 seconds. After block 2000, the required amount of time is 6000 seconds. More precisely, after block 2000 a utxo is not eligible for staking until 100 * the expected blocktime (i.e. 1 minute). For example, utxos on a one-minute block-time Smart Chain would be eligible for staking one-hundred minutes after their creation.

• The segids rotate through a queue to determine which segid has the most likely chance to stake a new block. The formula that determines this is based on the block height: (height % 64) = the segid0 for this height. For each block, the eligibility to stake a new block begins with segid[0], and then the eligibility expands to the next segment in queue at every two-second interval until the block is staked. For example, if segid[0] has not mined a new block within two seconds, the consensus mechanism opens up the priority to include the second, segid[1]. This continues either until the block is staked, or all 64 segid's are eligible to stake a new block. Once a block is staked, the height of the blockchain changes, pushing the segid[0] segment to the end of the queue, etc.

• By internal design, a utxo is more likely to win a block within a segid based on age of the utxo and amount of coins. Regarding the age eligibiility, the maximum maturity level is one month (e.g. after reaching one month of age, a utxo's likelihood of staking a coin does not further increase). The age of the utxo is set by the nlocktime property of the utxo, or if nlocktime is not set, the age is determined by the utxo's blocktime property.

📌 Examples

ac_stocks

(In development)

The ac_stocks parameter has to be used along with the ac_cbopret parameter to supply TICKERS of the Stocks (available at https://api.iextrading.com/1.0/tops/last) whose USD prices are to be included in the DTO.

📌 Examples

ac_supply

This is the amount of pre-mined coins you would like the chain to have.

The node that sets gen during the creation process will mine these coins in the genesis block.

If ac_supply is not set, ac_reward must be set, and a default value of 10 coins will be used in the genesis block. If ac_founders is set, the pre-mined coins will be mined to the founder's reward address.

The ac_supply parameter should be set to a whole number without any decimals places. It should also be set to less than 2000000000 to avoid 64-bit overflows.

📌 Examples

ac_snapshot

The ac_snapshot parameter defines the frequency with which a Smart Chain creates snapshots of the address - balance data.

Example

The following example instructs the Smart Chain to execute a snapshot once every 1440 blocks. (Approximately one snapshot per day.)

-ac_snapshot=1440

Payments Module Functionality

The ac_snapshot parameter is required by the paymentsairdrop method of the Payments Antara Module.

The user first executes the paymentsairdrop method to create a Payments plan that is designed to distribute airdrops to addresses on the chain.

The user then executes the paymentsrelease method to release payments based on the amounts in the addresses in the most recent snapshot, as recorded by the ac_snapshot customization.

The Payments Module features several customizations to control the nature of these automated airdrops.

ac_timelock...

-ac_timeunlockgte=satoshis -ac_timelockfrom=height -ac_timelockto=height

The ac_timelock... parameters enforce "coinbase locking".

In coinbase locking, the Smart Chain's block-reward feature behaves in a different manner compared to a default Smart Chain. Any block reward that is greater than or equal to the ac_timeunlockgte satoshi amount is temporarily locked. It will be unlocked (and therefore spendable) on a random block between the ac_timelockfrom and ac_timelockto heights.

The random unlock time for each reward is independent of the unlock time of other rewards.

For example:

./komodod -ac_name=HELLOWORLD -ac_supply=0 -ac_reward=10000000000 -ac_halving=10000 -ac_timelockgte=10000000000 -ac_timeunlockfrom=10000 -ac_timeunlockto=100000

For the first 10000 blocks, any rewards that are greater than or equal to 10000000000 are locked until a random block between 10000 and 100000.

ac_txpow

Setting -ac_txpow=1 enforces a transaction-rate limiter. This can help to prevent spam transactions on a Smart Chain.

ac_txpow forces all transactions (other than coinbase transactions) to have a txid starting and ending with 00.

This parameter is currently a proof of concept. Many of the traditional API commands, such as sendtoaddress or sendmany, are not currently supported. Instead, use createrawtransaction and signrawtransaction.

ac_veruspos

The ac_veruspos parameter is an alternative to ac_staked.

When activated, the chain uses Verus's proof of stake implementation instead.

The only valid value for this parameter is -ac_veruspos=50. (ac_veruspos does not have the same segid mechanism as -ac_staked.)