Breaking blockchain islands, reading Cosmos from four key words | Chain node AMA

In recent years, the blockchain ecosystem has experienced explosive growth, followed by a large number of projects and applications. Some people say that this is like an isolated island, and it is difficult for people on the island to communicate with each other.

Therefore, cross-chain interaction has become the focus of community attention. Among them, Cosmos is typical. Cosmos completes the design of the network layer and the consensus layer, and adds pluggable function modules in the application layer, which is convenient for developers to quickly build core functions, thus completing the development of the entire chain.

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On June 6th, Cosmos core developer Sunny Aggarwal and community leader Chjango Unchained acted as the guest chain node AMA, hoping to let more people understand the meaning of Cosmos and the cross-chain era through question and answer.

To understand Cosmos, you have to touch a lot of technical terms. This article is guided by four keywords and selects the main content of AMA so that readers can further understand this cross-chain star project. Be prepared to accept a technical "crit"!

Keyword 1: ATOM

ATOM is the token that can be used for staking in Cosmos Hub. Just like the PoW system requires computing power, Cosmos Hub needs to pledge ATOM to ensure its network is running normally.

I love Bitcoin 1: What are the characteristics of ATOM?

Chjango: ATOM is a Staking token, which means it is used as a digital version of special hardware, like GPUs, FPGAs and ASICs that mine on the PoW chain. Since Cosmos Hub is completely protected by Proof-of-Stake, a token ATOM is required as a unit of voting rights, which acts like a computing power.

Back to the essence of PoS, ATOM represents the "weight" of any Staker. Therefore, we don't care about the number of validators, but we should pay attention to the proportion of total voting rights. Voting rights are not evenly distributed to each validator. So, when you hear XX validators, what you really care about is the percentage of ATOMs that the XX validators are bound to in all 100 validators. A set of boxing: As a cross-chain project based on PoS, does it mean that every ATOM holder can participate in Cosmos network governance? How to operate specifically?

Chjango: Every ATOM holder has the opportunity to participate in the chain management of Cosmos Hub. It can be done easily with most wallets. Lunie.io is a full-featured desktop wallet that allows you to vote through its interface when logging in through the Ledger Hardware Wallet.

In Bonded PoS (BPoS), you have some "direct democracy", and you can vote for ATOM's validator, but if you don't agree with their vote, you can simply override it with your own vote. There is a list of wallets that support Cosmos on hub.cosmos.network, but keep in mind that not all of these wallets are reviewed, and not all of them allow you to vote directly in their wallet. Xinjiekou: A good verification node can make ATOM holders gain revenue. In contrast, malicious verification nodes also have the risk of losing Tokens. So, how do users choose the best validator?

Sunny: Look at their security settings, commission rates, social reputation, governance voting history, and more.

Keyword 2: Cosmos SDK

The Cosmos SDK is a modular development framework that allows developers to build blockchains based on specific applications, namely sidechains. The Cosmos SDK is used in the application layer of the public chain. It has covered a large number of pluggable function modules, which is convenient for developers to select specific modules (application direction) to develop their own blockchain.

My name is Ye Liangchen: The Cosmos SDK is a modular development tool that covers the functional modules of the application layer.

Sunny: The core modules included in the SDK include tokens, Staking, management, reward distribution, IBC (Cosmos's cross-chain communication protocol) and more. However, there are many modules that are being built by other chains. We are developing a public repository to list all of these community modules.

Keyword three: Tendermint

Tendermint is a collection of Cosmos network and consensus layers that guarantees Byzantine fault tolerance for any distributed ledger technology (DLT) or blockchain application. Simply put, this technology allows developers to personalize their own blockchain without having to think about consensus and the implementation of network transport.

Qingying 觅: Using the Tendermint algorithm, the communication cost between the certifiers is very high, which means that after the number of certifiers reaches a certain level, the speed will be much slower. Is there a solution to this problem?

Sunny: Yes, there are a few ideas: 1. BLS signature aggregation (you can combine signatures into gossip layers to reduce network load); 2. Pipelined Tendermint (many Tendermint at a time); 3. QUIC (currently we use TCP to Do a lot of things that should use UDP / QUIC).

Vigorously: What are the optimizations made by the popular Tendermint consensus protocol on the PoS Byzantine Fault Tolerance Algorithm (BFT)?

Sunny: The basic working principle of the Tendermint consensus algorithm is to tangibly and quickly complete the BFT. Byzantine fault tolerance from the perspective of cryptography, so that malicious nodes are cut. Tendermint has a rotating certifier for each block and is optimized for the operation of the public p2p gossip network, both of which are important to the public chain.

Tendermint is not the most complex BFT protocol in the world, but it is very practical and simple. Tendermint Core is probably the only production-level BFT consensus engine available today. No wine or sleep: Regarding Cartel Formation (the oligopoly problem in any economic framework), in the Casper system, the CTFG protocol explicitly uses internal audit incentives to defend against cartel forms. How does Tendermint avoid this? Forming a cartel?

Sunny: One of the lucky things about Cartel in Tendermint is that any cartel below 33% is invalid and they can't do anything malicious. We are developing incentives to make it harder and profitable to crack down on cartels (the best way to stop cartel formation is to spread distrust). For example, we can make you profit when you actively expose your cartel. Chain governance can also be a good anti-cartel mechanism, and governance can also punish community members who are found to be cartels.

Chjango: For Sunny's addition of chain management as an anti-cartel mechanism, Casper FFG has the same risks as Tendermint in the face of node collusion. On the other hand, Casper CBC theoretically adds anti-cartel mechanism through cryptographic economic suppression, but similarly, the role of CBC algorithm is largely theoretical. Gerry: Cosmos didn't pay attention to a very important issue, that is, the compatibility of security, efficiency and decentralization, especially the decentralization of the essence of the blockchain world?

Chjango: You just raised the famous Vlad triangle trade-off problem. Vlad Zamfir explains the basic trade-offs between settlement time, communication expenditures and number of nodes. If you want to maximize decentralization (high node count), then you must extend the settlement time, which means you will prefer a higher block time (for security reasons). On the other hand, Tendermint has a higher communication expenditure (>4KB independent signature), which is relatively more decentralized and can be settled faster than other spare blockchains running DPoS. There is currently no way to break through the physical limitations of trade-offs.

Keyword four: present and future

IBC Inter-Blockchain Communication, Cosmos's cross-chain communication protocol, is the key to Cosmos's chain-to-chain interoperability. The current deployment of intra-chain communications is the next important milestone for the Cosmos team. For the team, the most interesting milestone is the cross-chain interconnected blockchain that allows other chains created by developers to be interconnected with ATOM to prevent evil behavior.

Zhoujie: How is the current progress of the Cosmos project? Have you encountered any difficulties during the development process?

Chjango: Currently, the core developers of the Tendermint team are asking for advice on using IBC as a cross-chain solution project. You can track the IBC development repository at github.com/cosmos/ics.

We recently successfully separated the Gaia (Cosmos Hub) logic from the Cosmos SDK framework, enabling a complete separation between the Cosmos SDK and the Cosmos Hub. You can check out the new Cosmos Hub repository here: github.com/cosmos/gaia.

In business development, the Tendermint team works with key projects (cosmos.network/ecosystem) to get complementary solutions. For example, the Interledger protocol is a useful cross-chain payment solution that we believe will benefit users of the Cosmos SDK.

The Interchain Foundation has begun to increase its funding program, with the first grants ending recently after receiving a large amount of demand. (It will reopen the authorization application later this year after processing the first grant application.) You can find out more about ICF-funded projects on interchain.io.

ICF is funding a number of complementary projects like Thorchain that can help build the Interchain ecosystem, such as making Cosmos <> Ethereum two-way hooks. Yi Nan: How is Cosmos designed or planned in terms of cross-chain smart contracts and data privacy?

Chjango: We strongly encourage ecosystem contributors to expand some of the smart contract languages/virtual machines that are compatible with the Cosmos ecosystem. While smart contracts and privacy technologies like ZK-SNARKs and STARK are not roadmaps for the core developers of the Tendermint team, these are things that the Interchain Foundation (ICF) is raising to get other teams to do. Projects currently under development for this type have already applied for funding. For example, Kadena has applied for grants to integrate their smart contract language (Pact) into Tendermint. This may evolve as developers can launch Pact Zones in Cosmos, which is actually a smart contract chain that interoperates with the rest of the Cosmos network.

Xiao Zhang Zhang: You are currently focusing on the value cross-chain transfer. Is there a cross-chain communication road map with the next step?

Sunny: Yes, IBC is designed with versatility in mind, allowing users to transfer different types of data on it. This is like having a higher level of protocols on TCP/IP, such as HTTP, SMTP, FTP, etc. Again, there will be different agreements on top of IBC. We started with the token transport protocol, but would like to add more like NFT, oracle data, Agoric, etc.

Chjango: The first iterative step is to make the cross-chain assets safe to transfer. Roadmaps can become blurred over time – basic data transfers, NFT transfers, smart contract calls, etc. can be done through IBC, but these features need to be built step by step. This is a long-term goal, and it can be said to be the ultimate goal of IBC. Run: Can you tell us about Cosmos' ROADMAP and the community's next strategy?

Chjango: There is currently a high-level roadmap on cosmos.network/roadmap. The current deployment of intra-chain communication is the next important milestone we plan to achieve. Since IBC is the basis for ensuring the normal operation of other projects, it needs to be completed first. After IBC, we can build a viable Peg Zone, we can have Ethermint, and most importantly, we can establish cross-chain interconnection with Cosmos Hub.

The last one is the most interesting milestone for me: the cross-chain interconnected blockchain. This is different from shared security because you can't use the same validator to verify a chain in the same virtual machine as in Polkadot or ETH 2.0, but your chain can basically be interconnected with ATOM, so that Once there is malicious behavior in your chain, these perpetrators will be punished in ATOM.