NEAR is a decentralized application platform co-founded by Alexander Skidanov and Illia Polosukhin. It is built on top of NEAR Protocol, a sharded and developer friendly Blockchain. The network runs on Proof- of-stake consensus mechanism called Nightshade, which aims to offer scalability and low fees.
NEAR uses a novel consensus mechanism and sharding to achieve its goals.
Some of the key elements are:
- Sharding: NEAR uses horizontal shading technique to scale near-infinitely by distributing computation across multiple parallelized shards.
- Consensus: Consensus is achieved across all of the nodes across all of the shards using the new Nightshade algorithm.
- Staking Selection: To participate in the validation process, stakers are chosen randomly through a secure process and get incentivised to operate with good behaviour.
- Randomness: Unlike randomness approaches of other blockchains, NEAR’s randomness approach is unbiased, unpredictable and can tolerate upto ⅓ of malicious operators before liveness is affected and ⅔ malicious operators before anyone can actually influence its output. Best parts of all approaches are combined in one.
Cross-chain and Cross-shard communication
One of the biggest challenges a cross-chain or cross-shard communication faces is validating whether the incoming information is valid or not. Below are few approaches for validating cross chain transactions:
- Dual Validation: This method makes the validator on the receiving chain also validate on the sending chain. Used by Quarkchain, It has the downside that validators do not scale well.
- Trust the Transaction: This method simply assumes that if a transaction is received, it is a valid one. In this, you keep track of the total number of tokens in each economy so you cannot create new tokens but you could create invalid transfers between parties(basically, you can steal from them).
- Beacon Chain with rollbacks: This method verifies the state transitions of all the other chains using a small subset of validators and if they find any issue, the entire chain is rolled back.
NEAR focuses on the 3rd approach. To give more security to the network, validators are rotated among the shards so that one adaptive adversary is not able to corrupt them.
Now while some protocols rotate validators among shards on a daily basis, few protocols have gone a step ahead and rotate validators vary rapidly like within few minutes.
NEAR doesn’t use any of the two, it has its own way of approaching this, Nightshade algorithm.
This algorithm modifies the typical sharding idea and assumes that all of the shards combine together to produce a single block.
There is a leader validator assigned to produce each block. This validator must assemble the chunks which are provided to it during that block’s time period into the period’s block. The position of leader validator will rotate among existing validators and every block will be produced by a different leader. This leader does not accept transactions, only chunks.
Now each shard also follows the same technique, a leader will be assigned among the existing validators (shard has its own small set of validators pulled from the main validator pool) to produce its chunk and if this validator is not present then the shard will stall for that period. And the next assigned leader of the shard will take over this responsibility in the following period.
In order to provide additional security, NEAR uses Hidden Validators. Their job is to verify chunk produced by each shard. This activity doesn’t take place on blockchain, so validators are not visible to anybody. Instead they get their assignments individually by drawing a set of shard ids from a Verifiable Random Function (VRF).
This way they know which shard they have to verify but they are not able to corrupt them. As for doing that they must bribe a large percentage of total validators across all shards to reveal their masks.
As everything is determined randomly, the adversary doesn’t even know how many validators they’ll need to bribe in order to pull off a successful attack. This prevents attacks where an adversary broadcasts their intent and waits for the fishermen to come to them (revealing which shards they are validating).
In addition to Hidden validators, there is an additional layer of security provided by Fisherman. This can be done by any node operator permissionlessly. A Fisherman is able to provide the same “fraud proof” as hidden validators and thus they too can kick off the process of slashing and rollback.
So, Even if an adversary has successfully corrupted the validator pool to carry out an attack (chances of this happening are very very slim, almost impossible) there is always a chance that fisherman discovers this and thus everybody gets highly disincentivized.
NEAR is the native utility token on NEAR Protocol and each token is a unique asset in itself, which can be used for the following:
- To pay fees for processing transactions and storing data.
- To become a validator and run a validator node via staking NEAR token.
- To participate in governance votes to determine how the network’s resources are utilized and the future direction of NEAR.
Exchanges supporting NEAR:
This token is supported by some of the largest exchanges in Crypto world. It is available to be traded against BTC, USDT, BNB, ETH and BUSD. Here is a list of few exchanges,
- Binance – USDT, BUSD, BNB, BTC
- Huobi Global – USDT, BTC, ETH
- Gate.io – USDT
- WazirX – USDT
- MXC.Com – USDT
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