Beam is a privacy-focused blockchain that implements the Mimblewimble protocol to condense chain size and enable confidential transactions. Beam believes that its default privacy features and improved chain scalability will give it an edge over otherwise comparable privacy-focused cryptocurrencies, like Monero and Zcash. The project featured no pre-mine or token sale, with the project’s capped 262 million supply of Beam only available through block rewards split among miners and the project’s treasury. Beam’s CEO, Alexander Zaidelson, has previous experience as principal of CIRTech Fund, among other tech ventures. Beam announced mainet release on January 3rd of 2019.
Beam utilizes the Mimblewimble protocol to enable a less data intensive blockchain of transactions and to obfuscate details of transactions typically made public in systems like Bitcoin.
Privacy on Beam is safeguarded in several respects. Transactions are encrypted using Mimblewimble’s Confidential Transactions technique, which hides transaction amounts and sender/receiver information. Crucially, the technique permits transactions to be secured and validated without storing addresses on the Beam blockchain—a user just holds keys to the ‘unspent transaction outputs’ (UTXO) he or she owns. This enables Beam to improve privacy both by making transactions private by default (thus reducing the risks that identity revealing information can be deduced through other actors’ non-private transactions) and by obviating the need to store complete addresses on a publically accessible blockchain, as part of the transaction history verification processes (thus eliminating actors ability to deduce identity through analysis of blockchain records). The protocol further protects privacy by implementing Dandelion, a networking policy designed to prevent observers of network traffic from inferring useful information, and by implementing Bulletproofs, a form of zero knowledge range proof attached to every transaction and checked during validation to ensure transactions contain no negative values (which can create issues with monetary supply.)
Beam is a ‘compact blockchain’, meaning that less information needs to be stored on chain for purposes of validation than comparable blockchains—the project estimates the Beam blockchain will be 30% of Bitcoin’s size, below 70GB, when it reaches Bitcoin’s current scale. Beam can scale so in part because it only needs to store commitments, not address, on its blockchain, and in part because it implements Mimblewimble’s transaction cut-through techniques, which allows nodes to validate transactions without needing to store intermediate transactions. Besides being private and scalable, the Beam blockchain is also auditable, though this feature is strictly optional and cannot be enabled retrospectively.
Beam is a PoW blockchain, and mining utilizes the Equihash algorithm. Mining the Equihash algorithm requires a large amount of memory, as opposed to processing power, and is viewed by Beam as enabling more efficient mining, which is a reason the team choose the particular algorithm. Beam acknowledges that its choice of PoW will result in low transaction throughput, and is actively researching Lightning integration as a solution. Other features Beam is researching or actively developing include:
- Atomic swaps between BEAM and BTC
- Mimblewimble compatible hardware wallet integration
- A mobile wallet for Android
- Payment platform integration, specifically with BTCPay
Among its goals for 2019, Beam’s core team includes defining governance, with a ‘global community running Beam’ representing the team’s ultimate aim. While major decisions remain, the governing foundation, tentatively the ‘Beam Sovereign Money Foundation’, will be funded through part (20%) of block-reward splitting treasury allocations. The team intends to attract prominent industry figures to the foundation’s board of directors, and is establishing the organization as a Switzerland based non-profit with goals of improving the Beam protocol, promoting research, increasing awareness, and developing Beam’s privacy agenda.
Beam’s token, BEAM, is intended to function as a money, specifically by offering holders a unit of account, store of value and eventual means of exchange. BEAM is designed to be a deflationary coin, with a capped supply that halves every four years, starting ten years after mainet launch—90% of all Beam is scheduled to be emitted within the first thirteen years. Beam coin emission is split between miners and the project’s treasury, with block rewards apportioned in a 4:1 ratio between miners and the treasury in years two through five of the mainet launch. The treasury will be used to repay Beam investors (35% of treasury allocations), compensate the Core Team (45% of treasury allocations), and support the Beam Foundation (20% of treasury allocations).