What Is an Application-Specific Integrated Circuit (ASIC) Miner?

An application-specific integrated circuit (ASIC) is an integrated circuit chip designed for a specific purpose. An ASIC miner is a computerized device that uses ASICs for the sole purpose of “mining” digital currency. Generally, each ASIC miner is constructed to mine a specific digital currency. So, a Bitcoin ASIC miner can mine only bitcoin. One way to think about bitcoin ASICs is as specialized bitcoin mining computers optimized to solve the mining algorithm.

Developing and manufacturing ASICs as mining devices is costly and complex. However, because ASICs are built especially for mining cryptocurrency, they do the job faster than less powerful computers. As a result, ASIC chips for cryptocurrency mining have become increasingly efficient, with the latest generation hashing at 158 terahashes per second but only using 34.5 joules per terahash.

Understanding Application-Specific Integrated Circuit (ASIC) Miners

Instead of being general-purpose integrated circuits—like RAM chips or PC or mobile device microprocessors—ASICs employed in cryptocurrency mining are specific integrated circuits designed solely to mine cryptocurrencies.

Initially, Bitcoin’s creator(s) intended for bitcoin to be mined on central processing units (CPUs) of commonly used laptops or desktop computers. However, Bitcoin ASICs surpassed both CPUs and graphics processing units (GPUs) because of their reduced electricity consumption and greater computing capacity. After gaining traction in mid-2013, when other hardware mining devices started hitting bottlenecks in their mining, Bitcoin ASIC miners increased and retained their lead.

A hash is a long hexadecimal number used to identify blocks in a blockchain, called the block header hash or block hash. To mine a block, miners begin adding values to a hash to generate new ones until a number less than the target difficulty (original hash) is reached. This is called hashing. The more hashes that can be performed in a set period, the more likely a miner is to earn bitcoin. ASIC miners are optimized to compute hash functions efficiently and quickly.

Although mining cryptocurrencies can be an expensive proposition of declining profitability, many people are drawn to it. Despite the uncertain return on investment, would-be cryptocurrency miners are willing to incur high upfront expenses for pricey ASICs and pay significant ongoing costs for electricity in return for the prospect of earning cryptocurrency.

Development of the ASIC Miner

Cryptocurrency mining is required by a proof of work (PoW) blockchain like Bitcoin to carry out its operations. The mining process involves solving a block’s hash by randomly generating numbers until reaching a number below the target difficulty number. The first miner to find the solution to the puzzle closes the block. Each winner in the bitcoin mining competition receives a reward (a specific amount of bitcoin) along with the transaction fees for the transactions in that block.

In Bitcoin’s early days, any computer with adequate processing power could mine bitcoin. However, those days are long gone; bitcoin’s soaring popularity and growing acceptance have attracted hordes of crypto miners.

At the same time, cryptocurrency mining has become exponentially more difficult because the mining difficulty changes as miners enter and exit the network. Over time, the number of miners has constantly grown, which increased the difficulty. These developments have resulted in a race to harness the most “hashing power,” the term used to describe how many hashes per second a miner can generate (or the combined hashes per second of a networked mining rig or pool). ASIC miners came about as a result of this quest for more hashing power; modern Bitcoin ASICs can hash at more than 150 terahashes per second (nine zeros, or 150 x 10¹² hashes per second).

ASIC devices were popularized by Bitmain (headquartered in China), which dominates ASIC Bitcoin mining activities through its Antminer ASIC product range.

ASIC Miner Advantages

Though GPU and CPU mining rigs rely on components that have more than one function, ASIC miners are designed for the sole purpose of mining cryptocurrency. This singular focus makes an ASIC miner much more powerful and energy-efficient than a comparable GPU miner.

Because each cryptocurrency has its own cryptographic hash algorithm, an ASIC miner is designed to mine using that specific algorithm. For example, Bitcoin ASIC miners are designed to hash the SHA-256 algorithm, while Litecoin (LTC) uses scrypt (pronounced es-crypt). Though this means that an ASIC miner could technically mine any other cryptocurrency based on the same algorithm, most miners who invest in ASIC hardware designed to mine bitcoin or Litecoin stick to mining that specific cryptocurrency.

ASIC Miner Considerations

Before investing thousands of dollars in an ASIC mining rig, here are some factors to be considered:

• What coins can be mined? The list of cryptocurrencies that can be mined with ASICs is far smaller than those that can be mined with a GPU rig. Cryptocurrencies that can be mined with ASICs include Bitcoin, Litecoin, and several others.
• Rig location: Though GPU mining rigs can be located in one’s home, ASIC miners are louder and generate much more heat. This means that one’s home is not ideal for an ASIC miner, and alternate locations like a basement or garage with cooling need to be considered.
• Power consumption: The latest generation of ASIC machines are more energy-efficient than GPU rigs but consume tremendous power nevertheless. An ASIC miner based in one’s home may necessitate upgrading the electrical wiring system to handle the increased power load.
• Choosing a Bitcoin mining pool: Mining pools enable miners to combine the power of their ASIC miner rigs to mine bitcoin and share the rewards for successfully minted blocks. Factors to be considered when choosing a pool include its reputation, size, and payment rules.
• Return on Investment: Is the return on investment sufficiently high enough to justify the upfront cost of an ASIC miner and ongoing operating expenses?

What Is an Atomic Swap?

An atomic swap is an exchange of cryptocurrencies from separate blockchains. The swap is conducted between two entities without a third party’s involvement. The idea is to remove centralized intermediaries like regulated exchanges and give token owners total control.

The term atomic derives from the term “atomic state” in which a state has no substates; it either happens or it doesn’t—there is no other alternative. This refers to the state of the cryptocurrency transaction; it happens or it doesn’t.

Most atomic swap-enabled wallets and blockchains use smart contracts. Smart contracts are programs within blockchains that execute when certain conditions are met. In this case, the conditions are that each party agrees to the transaction before a timer runs out. Using a smart contract in the trade prevents either party from stealing a cryptocurrency from the other.

Atomic swaps are also called cross-chain atomic swaps.

Understanding Atomic Swaps

Each cryptocurrency is supported by a blockchain, designed only to accept transactions in specific tokens. For example, Bitcoin (BTC) has a blockchain, and ETH (ether) has another. You cannot easily exchange BTC and ETH without first converting to fiat currency then buying the other; another technique is to convert between cryptocurrencies and exchanges multiple times to get the one you want. Atomic swaps allow you to exchange tokens from different blockchains in one trade.

Decentralized exchanges can conduct atomic swaps for you. A decentralized exchange (DEX) has no central authority regulating it; it is a platform you can trade on without third parties. You can also choose from cross-chain swap providers, where you transfer your digital assets into another wallet, conduct the swap, and transfer them back out.

History of Atomic Swaps

The concept was conceived shortly after altcoins—cryptocurrencies other than Bitcoin—materialized. The creation of altcoins meant some cryptocurrency owners became interested in moving capital between coins. This type of token swap first appeared in September 2017, when an atomic swap between Decred and Litecoin was conducted.

Since then, startups and decentralized exchanges have implemented swaps and allowed users the same facility. For example, Lightning Labs, a startup that uses Bitcoin’s lightning network for transactions, has conducted off-chain swaps utilizing the technology.

Special cryptocurrency wallets have also been developed that are capable of cross-chain atomic swaps—Liquality has developed a wallet that will swap Bitcoin, ETH, and more.

Atomic Swap Process

In an atomic swap, two token owners agree to exchange their tokens for any amount they agree on. The smart contract program sees that they both agreed to it, so it executes the trade for them. The transaction is recorded in the blockchain and validated by the network nodes, and then a new block is opened for another transaction.

The transaction cannot be reversed. Both parties must agree to another transaction to exchange the tokens again if they would like them back.

Atomic swaps use Hash Timelock Contracts (HTLC) to automate the exchange of tokens. As its name denotes, HTLC is a time-bound smart contract between parties that involves generating one cryptographic hash on each end.

HTLC requires both parties to acknowledge receipt of funds within a specified timeframe. If one party fails to confirm the transaction within the timeframe, then the entire transaction is voided, and funds are returned. This eliminates counterparty risk, or the risk that one party will accept the offered coins and decline the transfer of their coins.

For instance, suppose Jane wants to convert 1 BTC to an equivalent number of Litecoins with John. She submits the transaction through an atomic swap-capable wallet. A cryptographic hash function generates a hex number to encrypt the transaction during this process. The process is repeated at John’s end.

Both Jane and John unlock their respective funds using their encrypted numbers. They have to do this within a specified timeframe, or the transfer will not occur. The HTLC within the blockchains then executes the trade.

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