This guide addresses as many questions you may have about Fantom as possible. Please refer to this FAQ section before asking questions on Discord. If your question is still unanswered, please reach out to us through the chat function on our website in the bottom right corner or join our Discord.
General questionsFTM tokenOpera networkTools
General questions
What is a consensus algorithm?
A consensus algorithm is a mechanism for reaching agreement among nodes in distributed networks. It removes the need for a central authority and allows the whole network to trustlessly agree on data and the ordering of events.
Nodes in the network maintain an exact copy of the ledger, allowing applications built on top of the consensus protocol to function correctly.
What is aBFT (Asynchronous Byzantine-fault-tolerant) consensus, and how is it different from blockchains such as Ethereum and Bitcoin?
aBFT consensus stands for “asynchronous Byzantine-fault-tolerant” consensus. When a network is said to be Byzantine fault tolerant, nodes can still agree on an ordering of events even if part of the network acts maliciously.
Asynchronous BFT allows nodes in the network to confirm blocks containing transactions without depending on any timing assumptions. This makes the network's confirmation of transactions faster without compromising security or decentralization.
When the network confirms a transaction, it achieves complete finality and cannot be changed or reverted. aBFT consensus reaches agreement on transactions even when some of the messages between nodes are lost, which makes the network more robust and resilient
Blockchains like Ethereum and Bitcoin are synchronous, and transactions are appended into blocks one at a time. They follow the longest-chain rule, in which the chain with the most blocks determines the final ordering of events. Transactions in earlier blocks are much more likely to be part of the final ordering of events than more recent transactions.
Therefore, these networks require multiple confirmations to ensure a transaction is permanently part of the blockchain. This behavior leads to slower transaction confirmation than in aBFT consensus.
What is finality?
Finality means that a transaction cannot be changed or reversed by any party. aBFT consensus algorithms such as Lachesis have a very low time to finality because they achieve absolute finality. Absolute finality means a transaction is considered final once included in a block.
In the case of Fantom, the Opera Chain can achieve finality in 1 to 2 seconds, while TxFlow can achieve finality in less than a second.
Conversely, Nakamoto consensus protocols rely on probabilistic finality. In this case, the probability that a transaction will not be reverted increases with time. The more blocks created on top of a block, thereby confirming it as correct, the more difficult and costlier it would be to revert a transaction in that block. At some point, it becomes theoretically impossible to alter older blocks, increasing the probabilistic finality to nearly 100%.
Bitcoin has a finality of 30 to 60 minutes; when using Bitcoin, you must wait a few block confirmations before considering the transaction final and irreversible. Ethereum has a finality of a few minutes.
What is TxFlow?
TxFlow is an aBFT middleware protocol designed for responsiveness. It runs with a traditional consensus algorithm such as Lachesis, which guarantees network security.
TxFlow can achieve sub-second latency, which makes it ideal for any application that requires instant confirmation. Check the Github and the TxFlow introduction.
FTM token
Is FTM an ERC20 token?
Fantom has an ERC20 token, but it cannot be used directly on the Opera mainnet.
Here is a breakdown of the different FTM tokens in circulation at the moment
1. Opera FTM: Used on Fantom’s mainnet Opera Chain2. ERC20: Exists on the Ethereum network
Note that Fantom Opera addresses share the same structure as Ethereum addresses (0x…), but they are not Ethereum addresses.
Can I send ERC20 FTM tokens to my Fantom Wallet?
No. You need to transfer them over to Fantom using a bridge.
What’s the purpose of the FTM token?
The FTM token has several use cases within the Fantom ecosystem. It plays an essential role in a well-functioning, healthy network.
1. Securing the networkFantom uses a proof-of-stake system that requires validators to hold FTM. Anyone with at least 50,000 FTM can run their validator node to earn rewards and secure the network.
Every FTM holder can delegate their tokens to a validator (while keeping full custody of their funds) to receive staking rewards. Validators then charge a small fee for their services.
By locking in their FTM, validators help the network to be decentralized and secure.
2. Paying for network feesTo compensate validators for their services and prevent transaction spam, every action performed within the Fantom network costs a small fee, which is paid in FTM.
3. Voting in on-chain governanceDecisions regarding the Fantom ecosystem are made using transparent on-chain voting. Votes are weighted according to the amount of FTM held by an entity. 1 FTM equals 1 vote.
4. Additional use casesFTM is used to earn APR/APY on many DeFi platforms.
How can I stake FTM?
Check out this guide.
Can I stake FTM on exchanges like Binance?
You cannot stake FTM on exchanges at the moment.
How to run a validator on Opera?
To run a validator node on Fantom’s Opera Chain, the following is required:
A minimum stake of 50,000 FTM;
Google GCP N2 instance or AWS i3en.xlarge with 4 vCPUs (3.1 GHz) and at least 1TB of local NVMe SSD storage (or equivalent).
Where can I store FTM?
You can store Opera FTM on our official mobile and desktop wallets. For a guide on how to use it, visit https://fantom.foundation/how-to-use-fantom-wallet/#installing-wallet/.
Please note that the above wallet only supports Opera Network FTM. They do not support ERC20 or BEP2.
Opera network
What is Opera?
Opera is Fantom's mainnet, a fully decentralized blockchain network with smart contract support. It is compatible with the Ethereum Virtual Machine and powered by Fantom’s aBFT consensus algorithm, Lachesis. Thus, smart contracts developed on Ethereum can run on Opera, increasing scalability and security.
Is Fantom compatible with Ethereum smart contracts?
Yes. Fantom is fully compatible with the Ethereum Virtual Machine (EVM) and supports Web3JS API and RPC.
All smart contracts written in Solidity or Vyper, compiled and deployed on Ethereum, are fully compatible with the Opera Network.
What programming languages does Fantom support?
Fantom’s Opera network supports all the smart contract languages that Ethereum supports for the EVM, including Solidity and Vyper.
When did Fantom mainnet go live?
The Fantom Opera Chain went live on 27 December 2019.
How is Fantom governed? What does on-chain governance look like?
The Fantom Foundation is currently in charge of the network's governance, advised by the community and validator nodes. We plan to launch a governance smart contract that will allow validators and token holders to determine Fantom's direction and approve changes to the underlying consensus via hard and soft forks.
Find out more details on how governance works on Fantom.
Tools
