Categories
Network

Polygon Matic


Polygon believes in Web3 for all.

Polygon is a decentralised Ethereum scaling platform that enables developers to build scalable user-friendly dApps with low transaction fees without ever sacrificing on security.

Polygon is a scaling solution for public blockchains.
Based on an adapted implementation of Plasma framework (Plasma MoreVP) – with an account based implementation (read more here), Polygon supports all the existing Ethereum tooling along with faster and cheaper transactions.

Polygon Network is a blockchain application platform that provides hybrid Proof-of-Stake and Plasma-enabled sidechains.

Architecturally, the beauty of Polygon is its elegant design, which features a generic validation layer separated from varying execution environments like Plasma enabled chains, full blown EVM sidechains, and in the future, other Layer 2 approaches such as Optimistic Rollups.

Currently, developers can use Plasma for specific state transitions for which Plasma predicates have been written such as ERC20, ERC721, asset swaps or other custom predicates.
For arbitrary state transitions, they can use PoS. Or both! This is made possible by Polygon’s hybrid construction.

To enable the PoS mechanism on our platform, a set of staking management contracts are deployed on Ethereum, as well as a set of incentivized validators running Heimdall and Bor nodes.

Ethereum is the first basechain Polygon supports, but Polygon intends to offer support for additional basechains, based on community suggestions and consensus, to enable an interoperable decentralized Layer 2 blockchain platform.

Polygon has a three-layer architecture:

  1. Staking and Plasma smart contracts on Ethereum
  2. Heimdall (Proof of Stake layer)
  3. Bor (Block producer layer)

Polygon smart contracts (on Ethereum)

Polygon maintains a set of smart contracts on Ethereum, which handle the following:

  • Staking management for the Proof-of-Stake layer
  • Delegation management including validator shares
  • Plasma contracts for MoreVP, including checkpoints/snapshots of sidechain state

Heimdall (Proof-of-Stake validator layer)

Heimdall is the PoS validator node that works in consonance with the Staking contracts on Ethereum to enable the PoS mechanism on Polygon. We have implemented this by building on top of the Tendermint consensus engine with changes to the signature scheme and various data structures. It is responsible for block validation, block producer committee selection, checkpointing a representation of the sidechain blocks to Ethereum in our architecture and various other responsibilities.

Heimdall layer handles the aggregation of blocks produced by Bor into a merkle tree and publishing the merkle root periodically to the root chain. This periodic publishing are called checkpoints.
For every few blocks on Bor, a validator (on the Heimdall layer):

  1. Validates all the blocks since the last checkpoint
  2. Creates a merkle tree of the block hashes
  3. Publishes the merkle root to the main chain

Checkpoints are important for two reasons:

  1. Providing finality on the Root Chain
  2. Providing proof of burn in withdrawal of assets

A bird’s eye view of the process can be explained as:

  • A subset of active validators from the pool are selected to act as block producers for a span. The Selection of each span will also be consented by at least 2/3 in power. These block producers are responsible for creating blocks and broadcasting it to the remaining of the network.
  • A checkpoint includes the root of all blocks created during any given interval. All nodes validate the same and attach their signature to it.
  • A selected proposer from the validator set is responsible for collecting all signatures for a particular checkpoint and committing the same on the main-chain.
  • The responsibility of creating blocks and also proposing checkpoints is variably dependent on a validator’s stake ratio in the overall pool.

Bor (Block Producer Layer)

Bor is Polygon block producer layer – the entity responsible for aggregating transactions into blocks.

Block producers are periodically shuffled via committee selection on Heimdall in durations termed as a span in Polygon. Blocks are produced at the Bor node and the sidechain VM is EVM-compatible. Blocks produced on Bor are also validated periodically by Heimdall nodes, and a checkpoint consisting of the Merkle tree hash of a set of blocks on Bor is committed to Ethereum periodically.

How is Polygon different from other implementations of Plasma?

Polygon’s implementation of Plasma is built on state-based side chains which run on EVM, while the other implementations of Plasma primarily use UTXOs which restricts them to being payment specific.
Having state based side chains allows Polygon to provide scalability for generic smart contracts as well.

Secondly, Polygon uses a public checkpointing layer which publishes checkpoints after periodic intervals (unlike checkpoints after every block in Plasma Cash) allowing the side chains to operate at high speeds while publishing the checkpoints in batches.

These checkpoints along with the fraud proofs ensure that Polygon’s side chains operate in a secure manner and any fraudulent activity can be detected on Ethereum mainchain and be penalized by slashing the stakes of the bad actors.
This mainchain security is supplementary to the PoS protocol security on the side chains.

📜Resources

📎 Bor Architecture: https://forum.matic.network/t/matic-system-overview-bor/126
📎 Heimdall Architecture: https://forum.matic.network/t/matic-system-overview-heimdall/125
📎 Checkpoint Mechanism: https://forum.matic.network/t/checkpoint-mechanism-on-heimdall/127

Categories
Network

Injective Protocol

Injective Protocol is a fully decentralized layer-2 DEX protocol built for the next generation of decentralized derivatives exchange.

The Injective Chain is a Tendermint-based IBC-compatible blockchain which supports a decentralized orderbook-based DEX protocol and a trustless ERC-20 token bridge to the Ethereum blockchain.

It is the first layer-2 fully decentralized exchange protocol for decentralized perpetual swaps, futures, and spot trading that unlocks the full potential of decentralized derivatives and borderless DeFi. Every component of the protocol has been built to be fully trustless, censorship-resistant, publicly verifiable, and front-running resistant.

By providing the unrestricted and unprecedented ability to express diverse views in the decentralized financial markets, we are striving to empower individuals with the ability to more efficiently allocate capital in our society.

Key Features & Highlights

  • Fully Decentralized: Injective transforms an exchange into a decentralized public utility by open-sourcing every single component of the exchange, from the front-end exchange interface to back-end infrastructure to orderbook liquidity.
  • Permissionless: Full decentralization turns the traditional business model of an exchange on its head, as we eliminate the technical barrier to entry for users by creating a permissionless and highly performant exchange for both spot and derivatives markets.
  • Censorship Resistant: Full decentralization combined with permissionless access ensures an open and unrestricted market, resistant to censorship.
  • Community Owned: Nodes on the Injective Chain are incentivized through token economics to act as order relayers, host a decentralized orderbook, and serve as a decentralized trade execution coordinator.
  • Scalable: Injective brings an order of magnitude speedup by scaling trade execution and settlement on layer-2.

Injective Protocol’s infrastructure is comprised of three principal components:

  1. Injective Chain
  2. Injective Exchange Service
  3. Injective Ethereum Bridge

Injective Chain

The Injective Chain is a layer-2 sidechain and Cosmos Zone connected to Ethereum.
The chain itself is built on top of Tendermint and allows for the transferring and trading of Ethereum-based assets on the Injective Chain.

The Injective Chain’s primary purpose is to power the Injective Exchange protocol, which is a decentralized peer-to-peer spot and derivatives exchange protocol. The protocol allows individuals to create and trade on arbitrary derivative markets.

Injective Exchange Service

Unlike traditional exchanges which serve as gatekeepers to the crypto industry, Injective transforms an exchange into a decentralized public utility. What truly differentiates Injective is that we bring every component of a decentralized exchange to the public. Everything — from the front-end exchange interface to back-end infrastructure to orderbook liquidity — is provided openly and for free.
This transforms the traditional business model of exchanges as we eliminate the technical barrier to entry for individuals to freely run a highly performative exchange.

Injective’s model rewards relayers in the Injective network for sourcing liquidity. By doing so, exchange providers are incentivized to better serve users as they compete amongst each other to provide better user experiences. Thus, this allows users from all around the world to access decentralized financial markets.

 

 

Categories
DAO Metaverse

Decentraland

Decentraland is a decentralized virtual reality platform powered by the Ethereum blockchain. Within the Decentraland platform, users can create, experience, and monetize their content and applications.

The finite, traversable, 3D virtual space within Decentraland is called LAND, a non-fungible digital asset maintained in an Ethereum smart contract.
Land is divided into parcels that are identified by cartesian coordinates (x,y). These parcels are permanently owned by members of the community and are purchased using MANA, Decentraland’s cryptocurrency token.
This gives users full control over the environments and applications that they create, which can range from anything like static 3D scenes to more interactive applications or games.

Some parcels are further organized into themed communities, or Districts. By organizing parcels into Districts, the community can create shared spaces with common interests and uses.
You can find a list of the original District Proposals on GitHub.
The content that makes up Decentraland is stored and distributed via a decentralized network while ownership and transactions are validated on the Ethereum blockchain.

FAQ

What equipment or software do I need to play in Decentraland?

A PC or Mac running Chrome, Firefox or Brave.

  • Can I play on a mobile device?
    For the moment we don’t support mobile devices. But please stay tuned!
  • Can I log in from multiple computers?
    Yes, you can run Decentraland from multiple computers as long as you have your digital wallet installed on each machine.
  • Can I use a different browser?
    While it may be technically possible to use another browser, we recommend Chrome, Firefox or Brave to ensure optimal performance.

Do I need a wallet to play in Decentraland?

If you want to fully enjoy the Decentraland experience, we recommend you get yourself a digital wallet. Digital wallets work as your personal account, keeping all your digital assets (such as names, collectibles, LANDs) and in-world progress safe.

If you choose to experience Decentraland Explorer without a wallet, the information will only be locally stored: you will be able to walk around, customize your Avatar and chat with others in-world, but you won’t have the chance to receive daily rewards, participate in events or log in with a different device using the same Guest ID and Avatar.

If this is the first time you’re hearing about digital wallets, we recommend reading Get a Wallet – Beginners Guide.

I lost my digital wallet! What happens with my account?

If you lose access to your wallet you will lose your Avatar, name, any of the wearables or NFT items stored within. Please remember to always keep your wallet recovery pass phrases in a safe and secure location.

What is MANA?

MANA is Decentraland’s fungible, ERC20 cryptocurrency token. MANA is burned, or spent, in exchange for LAND parcels. For a current summary of critical stats like total and circulating supply, please visit our MANA Token Information transparency dashboard. See the Glossary for more information.

Will I be able to buy things other than LAND with MANA?

Yes! In addition to burning MANA in exchange for LAND, users will be able to trade MANA with other users in exchange for goods and services hosted within Decentraland.

Some players have fancy wearables. How can I get them?

The Avatar editor provides a big selection of wearables and accessories – all for free. You can also buy exclusive wearables in the Decentraland Marketplace or earn them by participating in different events.

What do the collectibles colors mean?

Each collectible is assigned a rarity category, represented by a different name and color and denoting supply of collectible.

Their maximum issuance is:

  • Common: 100000
  • Uncommon: 10000
  • Rare: 5000
  • Epic: 1000
  • Legendary: 100
  • Mythic: 10
  • Unique: 1

Can I claim my Avatar name later?

Yes. Visit the Names page in the Builder to claim it. All you need is an installed digital wallet and at least 100 MANA to burn. Another alternative is to buy a name in the Decentraland Marketplace.

How can I block or report a player?

Click on another player’s Avatar to see their card, then click on the tab block to view options. By blocking a player you will still see them on screen but they won’t be able to write to you on the chat window. If you report a player, you will be able to bring a player’s conduct to the attention of Decentraland’s Community.

What is LAND?

LAND is a non-fungible digital asset maintained in an Ethereum smart contract. LAND is divided into parcels that are referenced using unique x,y cartesian coordinates. Each LAND token includes a record of its coordinates, its owner, and a reference to a content description file or parcel manifest that describes and encodes the content the owner wishes to serve on his or her land.

How large is a tile of LAND?

Land parcels are 16m x 16m, or 52ft x 52ft. Height is restricted based on these limitations.

What is an Estate?

Like LAND, an estate is a non-fungible digital asset. An estate is an association of two or more directly adjacent parcels of LAND. These parcels must be directly adjacent and cannot be separated by a road, plaza or any other parcel. By connecting parcels to form Estates, you can more easily manage your larger LAND holdings. Estates are especially useful when building larger scenes that span more than one parcel.

How can I buy LAND or Estates in Decentraland?

You can visit the Decentraland Marketplace to browse through all of the available LANDs or Estates of LAND that are currently for sale. On December 15th, 2017, we held our first LAND auction, called the Terraform Event, to distribute the first parcels of LAND to the community. The auction concluded in January 2018 and LAND tokens have been distributed to participants.

What does ‘owning’ virtual LAND mean and how does it work?

LAND within Decentraland is represented by non-fungible LAND tokens (meaning that each is unique and cannot be replicated) that track ownership on the Ethereum blockchain. Owning LAND within Decentraland is akin to owning any other unique, crypto asset like CryptoKitties or CryptoPunks, however you will be able to use your LAND within Decentraland to build three dimensional spaces and applications. LAND is built on our ERC721 standard, making it a digital asset that can be traded with other users, like other digital assets.

Why is LAND scarce?

Like CryptoKitties and CryptoPunks, LAND is a non-fungible digital asset. To ensure that the value of LAND parcels remains stable, the amount of land in Decentraland corresponds to the fixed, total amount of MANA.

Without LAND scarcity, many parcels would likely be left abandoned, negatively impacting the quality of content in Decentraland and the user experience.

Does Decentraland run on top of its own blockchain?

Decentraland uses the Ethereum blockchain to store and verify information about LAND ownership and LAND content. It does not run on its own independent blockchain. Content within Decentraland is hosted and served to users via a network of community-owned content servers.

Who validates transactions?

The Ethereum LAND smart contract registers any changes to the state of a parcel of LAND, such as a change in the contents of the LAND or a transfer of ownership. These changes are recorded and verified by the Ethereum blockchain.

How is content distributed?

The visual, audio and three dimensional content of Decentraland will be stored in a network of content servers. Anyone can submit a server to join this network, but it must be voted on by the community. This is handled by a Decentralized Autonomous Organization (DAO). When you visit Decentraland, the content needed to render your location will be pulled from the content servers. Each LAND token, stored on the Ethereum blockchain, is associated with an x,y location within the world and links to the content for that location.

What tools should I use to start building in Decentraland?

There are two ways to create 3D content for Decentraland:

  • The Builder is an easy drag and drop visual tool. You have access to a large library of pre-made items, including interactive items that react to player feedback. You can also import and use your own custom 3D models.
  • The SDK is for creating scenes writing code, which gives you much more power and flexibility.

Both tools can also be combined. You can create a scene visually with the Builder, then export it and work with its code to add interactive functionality. You can also use the SDK to create custom smart items and place these using the Builder.

You will be able to use tools like SketchUp, Blender, and Maya to create 3D models that you can then import into Decentraland, these models must be in .gltf or .glb format.

Will I be able to control who can see content on my parcels?

Yes. You will be able to control how certain content on your parcel is served to other users within the Decentraland platform. For example, you could make 3D models, images, video, or sound content only visible to a player in Decentraland after they have submitted a payment or fulfilled some other requirement.

However, remember that by uploading content to the content servers you are essentially making it publicly available since the content servers are a distributed file system. While we intend to make it possible to limit how that content is served to players through a Decentraland client, the content itself will always remain discoverable on the content servers.

You will be able to control who you can see and interact with (and who can see and interact with you) within Decentraland. For example, imagine that you have a house on your parcel and you only want to invite certain friends into your house. You will be able to specify which players you can see (and which players can see you) within your house, but you won’t necessarily be able to prevent anyone from seeing your house or its contents since the assets required to render your house reside on the content server.

Can I monetize my content?

Yes. You are free to decide whether you will charge other players to access your content and how you will implement said charge. Decentraland is in no way involved in the monetization of your content and does not guarantee any return, profit or income. The success of the platform depends entirely on the efforts of the users. Your fate, your success, and eventually your journey, depends on you, your efforts, your imagination.

I need support! Where can I contact you?

Join our Discord and visit our #help channel to ask whatever questions you have. We’ll answer as soon as possible. Our friendly community members can help too. While you’re there why not check out some of the other channels to learn more about Decentraland?

Categories
Network

Avalanche

Avalanche is an open-source platform for launching decentralized applications and enterprise blockchain deployments in one interoperable, highly scalable ecosystem. Avalanche is the first decentralized smart contracts platform built for the scale of global finance, with near-instant transaction finality. Ethereum developers can quickly build on Avalanche as Solidity works out-of-the-box.

A key difference between Avalanche and other decentralized networks is the consensus protocol. Over time, people have come to a false understanding that blockchains have to be slow and not scalable. The Avalanche protocol employs a novel approach to consensus to achieve its strong safety guarantees, quick finality, and high-throughput without compromising decentralization.

AVAX

AVAX is the native token of Avalanche. It’s a hard-capped, scarce asset that is used to pay for fees, secure the platform through staking, and provide a basic unit of account between the multiple subnets created on Avalanche. 1 nAVAX is equal to 0.000000001 AVAX.

Avalanche Consensus Protocol

Consensus Comparison

Protocols in the Avalanche family operate through repeated sub-sampled voting. When a validator is determining whether a transaction should be accepted or rejected, it asks a small, random subset of validators whether they think the transaction should be accepted or rejected. If the queried validator thinks the transaction is invalid, has already rejected the transaction, or prefers a conflicting transaction, it replies that it thinks the transaction should be rejected. Otherwise, it replies that it thinks the transaction should be accepted.

If a sufficiently large portion (alpha α) of the validators sampled reply that they think the transaction should be accepted, the validator prefers to accept the transaction. That is, when it is queried about the transaction in the future, it will reply that it thinks the transaction should be accepted. Similarly, the validator will prefer to reject the transaction if a sufficiently large portion of the validators replies that they think the transaction should be rejected.

The validator repeats this sampling process until alpha of the validators queried reply the same way (accept or reject) for beta β consecutive rounds.

In the common case when a transaction has no conflicts, finalization happens very quickly. When conflicts exist, honest validators quickly cluster around conflicting transactions, entering a positive feedback loop until all correct validators prefer that transaction. This leads to the acceptance of non-conflicting transactions and the rejection of conflicting transactions.

How Avalanche Consensus Works

It is guaranteed (with high probability based on system parameters) that if any honest validator accepts or rejects a transaction, all honest validators will accept or reject that transaction.

Learn more technical components of the Avalanche consensus protocol by reading the whitepaper.

Snowman Consensus Protocol

Snowman is a chain-optimized consensus protocol–high-throughput, totally-ordered, and great for smart contracts. Snowman is powered by the Avalanche consensus protocol. Both P-Chain and C-Chain implement the Snowman consensus protocol.

Key Features

Speed

Uses a novel consensus protocol, developed by a team of Cornell computer scientists, and is able to permanently confirm transactions in under 1 second.

Scalability

Capable of 4,500 transactions per second–an order of magnitude greater than existing blockchains.

Security

Ensures stronger security guarantees well-above the 51% standard of other networks.

Flexibility

Easily create custom blockchains and decentralized apps that contain almost any arbitrary logic.

Sustainability

Uses energy-efficient proof-of-stake consensus algorithm rather than proof-of-work.

Smart Contract Support

Supports the creation of Solidity smart contracts and your favorite Ethereum tools like Remix, Metamask, Truffle, and more.

Private and Public Blockchains

Create your own public or private blockchains.

Designed for Finance

Native support for easily creating and trading digital smart assets with complex, custom rulesets.

Avalanche Platform Overview

Avalanche features 3 built-in blockchains: Exchange Chain (X-Chain), Platform Chain (P-Chain), and Contract Chain (C-Chain). All 3 blockchains are validated and secured by the Primary Network. The Primary Network is a special subnet, and all members of all custom subnets must also be a member of the Primary Network by staking at least 2,000 AVAX.

Here are tutorials on creating a subnet and adding validators to a subnet.

Primary network

Subnets

A subnet, or subnetwork, is a dynamic set of validators working together to achieve consensus on the state of a set of blockchains. Each blockchain is validated by exactly one subnet. A subnet can validate many blockchains. A node may be a member of many subnets.

A subnet manages its own membership, and it may require that its constituent validators have certain properties. This is very useful, and we explore its ramifications in more depth below:

Compliance

Avalanche’s subnet architecture makes regulatory compliance manageable. As mentioned above, a subnet may require validators to meet a set of requirements.

Some examples of requirements include:

  • Validators must be located in a given country
  • Validators must pass a KYC/AML checks
  • Validators must hold a certain license

(To be abundantly clear, the above examples are just that: examples. These requirements do not apply to the Avalanche Primary Network.)

Support for Private Blockchains

You can create a subnet where only certain pre-defined validators may join and create a private subnet where the contents of the blockchains would be visible only to those validators. This is ideal for organizations interested in keeping their information private.

Separation of Concerns

In a heterogeneous network of blockchains, some validators will not want to validate certain blockchains because they simply have no interest in those blockchains. The subnet model allows validators to only concern themselves with blockchains that they care about. This reduces the burden on validators.

Application-Specific Requirements

Different blockchain-based applications may require validators to have certain properties. Suppose there is an application that requires large amounts of RAM or CPU power. A Subnet could require that validators meet certain hardware requirements so that the application doesn’t suffer from low performance due to slow validators.

Virtual Machines

A Virtual Machine (VM) defines the application-level logic of a blockchain. In technical terms, it specifies the blockchain’s state, state transition function, transactions, and the API through which users can interact with the blockchain. Every blockchain on Avalanche is an instance of a VM.

When you write a VM, you don’t need to concern yourself with lower-level logic like networking, consensus, and the structure of the blockchain. Avalanche does this behind the scenes so you can focus on the thing you would like to build.

Think of a VM as a blueprint for a blockchain; you can use the same VM to create many blockchains, each of which follows the same ruleset but is logically independent of other blockchains.

Why Virtual Machines?

At first, blockchain networks had one Virtual Machine (VM) with a pre-defined, static set of functionality. This rigid, monolithic design limited what blockchain-based applications one could run on such networks.

People who wanted custom decentralized applications had to create their own, entirely new blockchain network from scratch. Doing so required a great deal of time and effort, offered limited security, and generally resulted in a bespoke, fragile blockchain that never got off the ground.

Ethereum made a step toward solving this problem with smart contracts. Developers didn’t need to worry about networking and consensus, but creating decentralized applications was still hard. The Ethereum VM has low performance and imposes restrictions on smart contract developers. Solidity and the other few languages for writing Ethereum smart contracts are unfamiliar to most programmers.

Avalanche VMs (AVMs) make it easy to define a blockchain-based decentralized application. Rather than new, limited languages like Solidity, developers can write VMs in Go (other languages will be supported in the future).

Creating Your Blockchain and Virtual Machine

Avalanche supports the creation of new instances of the Avalanche VM.

Avalanche also supports creating custom blockchains with virtual machines.

Exchange Chain (X-Chain)

The X-Chain acts as a decentralized platform for creating and trading digital smart assets, a representation of a real-world resource (e.g., equity, bonds) with a set of rules that govern its behavior, like “can’t be traded until tomorrow” or “can only be sent to US citizens.”

One asset traded on the X-Chain is AVAX. When you issue a transaction to a blockchain on Avalanche, you pay a fee denominated in AVAX.

The X-Chain is an instance of the Avalanche Virtual Machine (AVM). The X-Chain API allows clients to create and trade assets on the X-Chain and other instances of the AVM. See this for more details.

Platform Chain (P-Chain)

The P-Chain is the metadata blockchain on Avalanche and coordinates validators, keeps track of active subnets, and enables the creation of new subnets. The P-Chain implements the Snowman consensus protocol.

The P-Chain API allows clients to create subnets, add validators to subnets, and create blockchains.

Contract Chain (C-Chain)

The C-Chain allows for the creation smart contracts using the C-Chain’s API.

The C-Chain is an instance of the Ethereum Virtual Machine powered by Avalanche.