Ren (REN) is an open protocol created to provide interoperability and liquidity between different blockchain platforms, allowing everyone to transfer both new and existing assets across various blockchains through a global user network.
Formerly known as Republic Protocol, Ren completed its initial coin offering (ICO) in 2018, raising 34 million dollars and launched its core product, the RenVM virtual machine mainnet, in May 2020. The protocol's native token, REN, serves as a bond for the nodes, known as Darknodes, that power the RenVM. Ren aims to remove barriers related to liquidity between blockchains, thereby expanding the interoperability and accessibility of decentralized finance (DeFi).

RenVM is a virtual computer network that creates a virtual machine. The machines that power the network that makes up RenVM are called Darknodes, and the Ren virtual machine is protected by the DarkNodes network. Anyone can run a DarkNode, provided they lock a certain amount of REN tokens in smart contracts.
Ren DarkNodes help power the Ren virtual machine by adding bandwidth, computing power, and storage capacity to the network, allowing users to move crypto assets between Blockchains.
In return for helping maintain the network, DarkNode operators earn rewards in the form of REN tokens from network fees.

Ren was founded in 2017 by software developer Taiyang Zhang and Loong Wang. The platform, initially named Republic Protocol, was rebranded to Ren in 2019. Zhang, who has experience in the cryptocurrency sector, is also the co-founder of the crypto hedge fund Virgil Capital. Before Ren, Zhang founded a software and web development venture, Neucode, in 2014. Neucode's other co-founder, Jaz Gulati, now works as a software developer for Ren.

Ren utilizes a special virtual machine that deploys smart contract code to the Ren network to manage and execute its complex transactions. Virtual machines are emulations of physical computers that can perform computations across a distributed network without revealing underlying information. To achieve this, Ren's virtual machine uses zkSnarks, an encryption technique popularized by Zcash to protect transactions, and Shamir's Secret Sharing scheme to break up orders for hiding information from nodes.
The Ren team argues that this design allows anyone accessing Ren to finance an application on any blockchain without revealing information about themselves or their transactions.
For instance, with Ren, users can lock their Bitcoins or other crypto assets in a smart contract and receive the equivalent in ether on the Ethereum blockchain. From there, Bitcoin holders can access Ethereum's decentralized finance (DeFi) products using Ren without having to sell their Bitcoins or transfer their assets across blockchains.
Using Ethereum tokens, a user can participate in the DeFi ecosystem of Ethereum, including lending and borrowing platforms like Compound or Aave. Throughout this process, the user's Bitcoins remain locked in the Ren software. To unlock their funds, users need to use the REN cryptocurrency to make payments to nodes for operating and maintaining the network.

To exchange assets between blockchains, the Ren virtual machine accepts tokens from one chain and creates new tokens representing the originals on another chain through RenBridge.
For example, a user can send Bitcoin to the RenVM, which then creates a new token called renBTC on Ethereum that represents the original Bitcoins. The Ren virtual machine holds the original funds in storage and allows the transaction to be reversed when the user wants to retrieve their bitcoins.
As of 2020, the Ren virtual machine can swap Bitcoin, Bitcoin Cash, and Zcash to Ethereum. Since its launch in May 2020, over 1.2 billion dollars worth of assets have been exchanged using the Ren virtual machine.

REN, Ren's native cryptocurrency, is used to pay for transactions on the Ren network. DarkNode operators need to stake 100,000 REN to run a node. Since running a DarkNode requires REN tokens and the total fixed supply of REN is one billion, the possible number of DarkNodes is limited. This can help increase the demand for REN tokens.
Unlike other cryptocurrencies, users do not need to purchase or hold REN to access its platform. Instead, users pay fees in the cryptocurrency of the blockchain they are conducting economic activities on.

Ren is a complex platform with multiple uses but is designed to overcome barriers to entry and investment in DeFi projects. As an add-on, it allows DeFi projects to offer foreign crypto assets such as Bitcoin (BTC) and Zcash (ZEC). More broadly, users can essentially swap any token between any two blockchains without intermediate steps like using "wrapped" versions of tokens, such as Wrapped Bitcoin (WBTC) and Wrapped Ethereum (WETH).
Ren collects various fees for internal operations, but most do not go directly to profitability; instead, they pay miners. As an ERC-20 token, REN attracts variable gas fees for power transactions.
REN users can engage in economic activity on any blockchain of their choice, regardless of the cryptocurrencies in their portfolios. Therefore, users wanting access to all existing applications and protocols running on blockchains may prefer using REN.

REN, an ERC-20 standard token, has a fixed supply, and thus, its total and maximum supply is set at 1,000,000,000 REN, with 881,153,018 of these currently in circulation.
Ren conducted a private sale in 2018, selling 56.5% of the REN token supply and raising 28.9 million dollars in ETH. Investors such as Polychain Capital and FBG Capital were among the participants.
Ren then conducted a public token sale, selling 8.6% of the token supply and raising 4.8 million dollars in ETH. In total, 65.2% of REN tokens were sold in various sale events, surpassing 30 million dollars. The remaining tokens are allocated to the team and advisors (19.9%), community development (5%), and a company reserve (9.9%).

RenVM is a Byzantine fault-tolerant protocol that facilitates secure multi-party computation (sMPC) for ECDSA threshold key generation and signing. This allows RenVM to securely manage private keys (ECDSA) across different blockchains, enabling the shift (i.e., interoperability) of tokens between these blockchains.