/FSC

Primary LanguageGoGNU Lesser General Public License v3.0LGPL-3.0

FON Smart Chain

FON Smart Chain is a brand new public chain. The FON Smart Chain relies on a system of 21 active validators with Proof-of-Stake (APoS) consensus that supports short block times and lower fees. The validator candidates with the most stakes will become validators and produce blocks. Double-signature detection and other slashing logic ensure security, stability, and chain finality. In addition to the 21 active validators, FSC will introduce more validators, such as another 20 inactive validators, as backups into the validator set, which will be referred to as "candidates".

FON Smart Chain starts its development based on go-ethereum fork. So you may see many toolings, binaries and also docs are based on Ethereum ones, such as the name “geth”.

API Reference

Candidates will have bad influence in the FSC Mainnet and charge gas fees, but have much less chance than the official sponsor's 21 sets of elections. Unavailable candidates will also be affected, outperforming. For the purpose of ensuring quality and to help ensure that in this case, if the majority of the FSC setters are attacked in 21 verifications, in the genesis block, the team verified a range to guarantee the public chain's normal operation.

FON Smart Chain also supports EVM-compatible smart contracts and protocols. Cross-chain transfers and other communications are possible thanks to native support for interoperability：

  • Autonomous blockchain: Provides safety and security through elected validators.
  • EVM-compatible: Supports all the existing Ethereum tooling along with faster finality and cheaper transaction fees.
  • Interoperable: Comes with efficient native dual chain communication; Optimized for scaling high-performance dApps that require fast and smooth user experience.
  • Distributed with on-chain governance: Proof of Staked Authority brings in decentralization and community participants. As the native token, FON will serve as both the gas of smart contract execution and tokens for staking.

More details in White Paper.

Key features

Proof of Staked Authority

Although Proof-of-Work (PoW) has been approved as a practical mechanism to implement a decentralized network, it is not friendly to the environment and also requires a large size of participants to maintain the security.

Proof-of-Authority(PoA) provides some defense to 51% attack, with improved efficiency and tolerance to certain levels of Byzantine players (malicious or hacked). Meanwhile, the PoA protocol is most criticized for being not as decentralized as PoW, as the validators, i.e. the nodes that take turns to produce blocks, have all the authorities and are prone to corruption and security attacks.

Other blockchains, such as EOS and Cosmos both, introduce different types of Deputy Proof of Stake (DPoS) to allow the token holders to vote and elect the validator set. It increases the decentralization and favors community governance.

Native Token

FON will run on FON Smart Chain in the same way as ETH runs on Ethereum so that it remains as native token for FSC. This means, FON will be used to pay gas to deploy or invoke Smart Contract on FSC

Building the source

Many of the below are the same as or similar to go-ethereum.

For prerequisites and detailed build instructions please read the Installation Instructions.

Building geth requires both a Go (version 1.14 or later) and a C compiler. You can install them using your favourite package manager. Once the dependencies are installed, run

make geth

or, to build the full suite of utilities:

make all

Executables

The Fsc project comes with several wrappers/executables found in the cmd directory.

Command Description
geth Main FON Smart Chain client binary. It is the entry point into the FSC network (main-, test- or private net), capable of running as a full node (default), archive node (retaining all historical state) or a light node (retrieving data live). It has the same and more RPC and other interface as go-ethereum and can be used by other processes as a gateway into the FSC network via JSON RPC endpoints exposed on top of HTTP, WebSocket and/or IPC transports. geth --help and the CLI page for command line options.
clef Stand-alone signing tool, which can be used as a backend signer for geth.
devp2p Utilities to interact with nodes on the networking layer, without running a full blockchain.
abigen Source code generator to convert Ethereum contract definitions into easy to use, compile-time type-safe Go packages. It operates on plain Ethereum contract ABIs with expanded functionality if the contract bytecode is also available. However, it also accepts Solidity source files, making development much more streamlined. Please see our Native DApps page for details.
bootnode Stripped down version of our Ethereum client implementation that only takes part in the network node discovery protocol, but does not run any of the higher level application protocols. It can be used as a lightweight bootstrap node to aid in finding peers in private networks.
evm Developer utility version of the EVM (Ethereum Virtual Machine) that is capable of running bytecode snippets within a configurable environment and execution mode. Its purpose is to allow isolated, fine-grained debugging of EVM opcodes (e.g. evm --code 60ff60ff --debug run).
rlpdump Developer utility tool to convert binary RLP (Recursive Length Prefix) dumps (data encoding used by the Ethereum protocol both network as well as consensus wise) to user-friendlier hierarchical representation (e.g. rlpdump --hex CE0183FFFFFFC4C304050583616263).

Running geth

Going through all the possible command line flags is out of scope here (please consult our CLI Wiki page), but we've enumerated a few common parameter combos to get you up to speed quickly on how you can run your own geth instance.

Hardware Requirements

The hardware must meet certain requirements to run a full node.

  • VPS running recent versions of Mac OS X or Linux.
  • 1T of SSD storage for mainnet, 500G of SSD storage for testnet.
  • 8 cores of CPU and 32 gigabytes of memory (RAM) for mainnet.
  • 4 cores of CPU and 8 gigabytes of memory (RAM) for testnet.
  • A broadband Internet connection with upload/download speeds of at least 10 megabyte per second
$ geth console

This command will:

  • Start geth in fast sync mode (default, can be changed with the --syncmode flag), causing it to download more data in exchange for avoiding processing the entire history of the FON Smart Chain network, which is very CPU intensive.
  • Start up geth's built-in interactive JavaScript console, (via the trailing console subcommand) through which you can interact using web3 methods (note: the web3 version bundled within geth is very old, and not up to date with official docs), as well as geth's own management APIs. This tool is optional and if you leave it out you can always attach to an already running geth instance with geth attach.

Configuration

As an alternative to passing the numerous flags to the geth binary, you can also pass a configuration file via:

$ geth --config /path/to/your_config.toml

To get an idea how the file should look like you can use the dumpconfig subcommand to export your existing configuration:

$ geth --your-favourite-flags dumpconfig

Programmatically interfacing geth nodes

As a developer, sooner rather than later you'll want to start interacting with geth and the FON Smart Chain network via your own programs and not manually through the console. To aid this, geth has built-in support for a JSON-RPC based APIs (standard APIs and geth specific APIs). These can be exposed via HTTP, WebSockets and IPC (UNIX sockets on UNIX based platforms, and named pipes on Windows).

The IPC interface is enabled by default and exposes all the APIs supported by geth, whereas the HTTP and WS interfaces need to manually be enabled and only expose a subset of APIs due to security reasons. These can be turned on/off and configured as you'd expect.

HTTP based JSON-RPC API options:

  • --http Enable the HTTP-RPC server
  • --http.addr HTTP-RPC server listening interface (default: localhost)
  • --http.port HTTP-RPC server listening port (default: 8545)
  • --http.api API's offered over the HTTP-RPC interface (default: eth,net,web3)
  • --http.corsdomain Comma separated list of domains from which to accept cross origin requests (browser enforced)
  • --ws Enable the WS-RPC server
  • --ws.addr WS-RPC server listening interface (default: localhost)
  • --ws.port WS-RPC server listening port (default: 8546)
  • --ws.api API's offered over the WS-RPC interface (default: eth,net,web3)
  • --ws.origins Origins from which to accept websockets requests
  • --ipcdisable Disable the IPC-RPC server
  • --ipcapi API's offered over the IPC-RPC interface (default: admin,debug,eth,miner,net,personal,shh,txpool,web3)
  • --ipcpath Filename for IPC socket/pipe within the datadir (explicit paths escape it)

You'll need to use your own programming environments' capabilities (libraries, tools, etc) to connect via HTTP, WS or IPC to a geth node configured with the above flags and you'll need to speak JSON-RPC on all transports. You can reuse the same connection for multiple requests!

Note: Please understand the security implications of opening up an HTTP/WS based transport before doing so! Hackers on the internet are actively trying to subvert FSC nodes with exposed APIs! Further, all browser tabs can access locally running web servers, so malicious web pages could try to subvert locally available APIs!

License

The Fsc library (i.e. all code outside of the cmd directory) is licensed under the GNU Lesser General Public License v3.0, also included in our repository in the COPYING.LESSER file.

The Fsc binaries (i.e. all code inside of the cmd directory) is licensed under the GNU General Public License v3.0, also included in our repository in the COPYING file.