The Helium Version Number

This is the current version number of the Helium application.

The Maximum Number of Helium Coins

This is the maximum number of Helium coins that can come into existence. We will call a helium coin a helium, and a number of helium coins will be called heliums.

A fixed number of heliums are initially created and distributed in the genesis block. The genesis block is a hard-coded block that bootstraps the block creation process. In Bitcoin, Satoshi Nakamoto created and distributed 50 bitcoins in the genesis block.

Subsequently, new heliums are created as blocks are added to the Helium blockchain. Note that the maximum number of heliums that can be created is identical to the maximum number of bitcoins that can be produced in the Bitcoin ecosystem.

The Smallest Helium Currency Unit

HELIUM_CENT is the smallest subdivision of a helium that is possible. Observe that a hundred million Helium cents is equal to a helium. This definition corresponds to the definition of a satoshi in Bitcoin.

Helium Block Size

MAX_BLOCK_SIZE is the maximum size of a Helium block in bytes. The maximum size of a block determines the maximum number of Helium transactions that can be included in a block⁶ and a fortiori the average number of transactions in a block.

The Maximum Transaction Inputs

The Maximum Transaction Outputs

The Locktime Interval

An entity creating a transaction can specify that this transaction is not to be processed until a certain amount of time has elapsed. This will prevent miners from including this transaction in a block to be mined until this time interval has elapsed. Elapsed time is in seconds.

MAX_LOCKTIME specifies the maximum amount of time in seconds that a transaction can be locked from the time of its creation. We do not want to indefinitely lock transactions or lock transactions for very long periods of time. This can give rise to denial-of-service attacks as transaction caches maintained by miners become clogged with future transactions.

The preceding configuration parameter sets the maximum period of time that a transaction can be locked to seven days.

The Coinbase Interval

This positive integer specifies the number of new blocks that must be mined after a previous reference block, before a coinbase transaction in the reference block can be spent. When a miner mines a block, he is rewarded with the issuance of a fixed amount of new cryptocurrency. This new currency is presented to the miner in a coinbase transaction in the block. The coinbase interval parameter precludes a miner from spending a coinbase transaction until a certain number of new blocks have been added to the blockchain.

In Helium, a new block is mined every ten minutes approximately, so Helium coinbase transactions are locked for approximately 1000 minutes.

Nonce

This is a seed value. NONCE is the starting value that will be used in mining proof-of-work computations. We will discuss this use of nonces subsequently.

The Difficulty Number

The DIFFICULTY_BITS parameter lets us adjust the DIFFICULTY_NUMBER. In Helium as well as Bitcoin, mining a block involves solving a difficult mathematical problem. The DIFFICULTY_NUMBER determines how difficult this problem is and hence the average amount of time it will take to solve this problem.

A block is said to be mined when this difficult problem is solved by a Helium mining node. The node that solves this problem is entitled to append the mined block to the blockchain and is entitled to a reward of freshly mined heliums as well as the transaction fees attached to all of the transactions in the mined block.

Retarget Interval

Helium attempts to mine new blocks every ten minutes. After 1000 new blocks have been mined, Helium uses an algorithm to adjust the DIFFICULTY_NUMBER so that blocks are mined every ten minutes on average.

The Bitcoin algorithm also attempts to mine a new block every ten minutes on average. Litecoin, which is quite similar to Bitcoin, attempts to mine new blocks every two minutes on average.

The Mining Reward

The MINING_REWARD is the amount of new heliums in HELIUM_CENTS that are created and awarded to a mining node that successfully mines a block. The initial mining reward in Helium is five billion HELIUM_CENTS or five Helium coins (five heliums). This reward corresponds to the initial mining reward in Bitcoin.

In Helium as well as Bitcoin, the mining reward algorithm halves the mining reward periodically. The point in time when the reward is halved depends upon the number of blocks that have already been mined. Because of this periodic halving, the mining reward asymptotically approaches zero.

A cryptocurrency mining algorithm does not have to halve the reward periodically. There are cryptocurrencies where the number of coins that are created remains constant or varies according to some formula.

Bitcoin came into existence on January 3, 2009, when Satoshi Nakamoto created and mined the genesis block. The mining reward was 50 bitcoins for this block and every block that was mined thereafter. In 2012, this mining reward was halved to 25, and in 2016, the reward was again halved to 12.5 bitcoins. In 2020, the reward was halved to 6.25 bitcoins.

Since the only way to create new heliums or bitcoins is through the mining process (aside from an initial distribution in the genesis block), the mining algorithms in these two cryptocurrencies create an upper limit on the number of heliums or bitcoins that can be created. Thus, these algorithms create a scarcity of heliums and bitcoins over time, and this scarcity theoretically enhances the value of these cryptocurrencies.

Reward Interval

The REWARD_INTERVAL determines the number of additional blocks that must be mined in order to halve the mining reward. For example, after two hundred and ten thousand new blocks have been mined, the mining reward will be halved. This number is identical to the interval used in Bitcoin.