blockchain

问题 I came across Hyperledger fabric client which has methods/functions to authenticate new members into blockchain network. But I am not sure how I can authenticate new users into a channel in blockchain network. Can i use channel configuration(configtx) in hyperledger fabric to invite/register new participants into a channel? Link to channel configuration :http://hyperledger-fabric.readthedocs.io/en/latest/configtx.html#channel-creation 回答1: you can use fabric-ca. Fabric-ca provides several

问题 Closed . This question needs to be more focused. It is not currently accepting answers. Want to improve this question? Update the question so it focuses on one problem only by editing this post. Closed last year . most of the articles cited Blockchain as a distributed database. Does it mean we can store any type of data in blockchain like audio, video ,pdf? 回答1: Think of blockchain as a relatively slow, very expensive database that provides excellent resistance to hacking and corruption. It's

问题 I just got chance to work on Ethereum, block-chain based platform. But I don't have a clear idea in which scenarios this is used, any real life use of this.Could anybody help me understand blockchain based platform and its real life uses? 回答1: Welcome to blockchain world.Don't get demotivated, Blockchain area is relatively new & hard to find good tutorials.I also started learning blockchain related technologies a month ago & I would like to share some ideas about Blockchain & Ethereum.Since

问题 I'm in the process of creating an Ethereum DApp. The DApp consists of users who have associated data like email, name, and a profile picture. I would like to store the contents of the user within IPFS as a JSON object and reference this on chain using the IPFS hash. How could I go about associating this data with a particular user? In the sense, that subsequent interactions with the DApp connect the user with the data stored in IPFS. Is this done using the users account hash with a password

问题 I deployed a chaincode to a network of peers. It was unsuccessful. I looked at a peer's log and saw an error message: Error building images: Tag latest not found in repository docker.io/hyperledger/fabric-baseimage. 回答1: Pull a specific base image from https://hub.docker.com/r/hyperledger/fabric-baseimage/ using docker pull hyperledger/fabric-baseimage:<tag name> Check the image id of the downloaded image using docker images Tag this image as latest docker tag <imageID> latest 回答2: you should

问题 I am running blockchain demo which is provided by IBM mentioned in below link : https://github.com/IBM-Blockchain/marbles I have run Hyper ledger Fabric network on one linux system and 3 more clients on another 3 virtual instance on which my marbles client is running. It is working proper. If we do any transactions then it will affect all the 3 client, So, now if I want to see the all the transactions details, from where I can see it? Is there any database or any files on client side? Please

问题 Watching many examples in Hyperledger Fabric I found two ways to achieved a key: Let's suposse we have two fields visa and type of visa. Visa: "1212323" Type of Visa: "Student Visa" So we can create a key neither: Using CompositeKey function provide by stub key, err := stub.CreateCompositeKey(indexName,[]string{visa, typeVisa}) stub.PutState(key, value) Concatenating the two fields stub.PutState(visa+typeVisa, value) What is the difference between those two approaches? What is the best

问题 I did the tutorial to deploy to a multi org fabric network and it worked successfully . Now i have two admin cards - alice@trade-network , bob@trade-network and two identities/cards issued by them - jdoe@trade-network , dlowe@trade-network Now i have given access control rules stating that jdoe (trader1-org1) and dlowe(trader2-org2) can only view their own records Thus when i connect to their respective business cards i am able to view only their records . Now i can start two rest servers

问题 While running a corDapp(corDapp-example) for the first time using Kotlin-source, the IntelliJ throws this error - "error Class 'com.example.NodeDriverKt' not found in module 'cordapp-example". I looked for this class in my project structure and I can see a file named NodeDriver.kt which contains a function "main" but I could not see any class declaration. Any solution to remove this error would be much appreciated.IntelliJ 回答1: i had this same problem with the example cordapp. I was able to

问题 I have setup a HyperLedger Fabric V1.0 network with 4 organisations each having 1 peer by following the steps Building Your First Network. Now I have org1.example.com - with peer : peer0.org1.example.com and msp : Org1MSP org2.example.com - with peer : peer0.org2.example.com and msp : Org2MSP org3.example.com - with peer : peer0.org3.example.com and msp : Org3MSP org4.example.com - with peer : peer0.org4.example.com and msp : Org4MSP And now I can install the chaincode to peers and