When I was tasting the fabric, I found many other blockchain projects, like Composer, Cello, Explorer. They are all belong to Hyperledger. I'm very confused that there are so many projects. Should I learn all of them? It seems each project plays a role in the blockchain. BUT:
What's the relation between them?
I draw a picture to explain my question. The picture is not correct, I just want to make my question clear.
If I figure it out, when we want to use the blockchain in our project, I can just study few of them, and use them appropriately.
Fabric provides a framework to set up a blockchain network. It is data/application agnostic.
Composer provides a set of tools to define a business network on top of Fabric. This provides a higher level of abstraction than Fabric where the data are essentially just bits. With Composer you can define assets, transactions, etc.
Cello helps with provisioning of the network.
Explorer simply provides a web based interface to explore what's on a blockchain.
Fabric is a permissioned blockchain distributed ledger, it is at the end; an implementation of a permissioned blockchain.
Hyperledger project comprises a suite of tools for building blockchain business networks, what they name it "Hyperledger Composer".
it is used for developing,testing, deploying application on blockchain
also it is used for integrating your blockchain with external systems,
Cello, is a blockchain provision and operation system, which helps manage blockchain networks, and make the blockchain as service BaaS, it is not a blockchain, but it is used to manage the blockchain network.
Check this link for better understanding Cello
Hyperledger Cello
Explorer provide you KPI that show the blockchain
Cello is admin tool that help you to monitor the host and network with and container inside it, actually cello using fabric script if you take around in fabric you will find byfn (build your first network) script that setup container and example peer.
so cello uses this script to create container and show to you status of this and delete it or edit.
composer provide a tools to help you create your business card and your smart contract to write your smart contract you need to write acl(access control language which define rule),your logic , define participant and assets.
then composer will create bna archive file and install it on blockchain.
there is some module in composer like playground and restserver and also there is generator for frontend
fabric is the framework that setup the blockchain network, it's the base that cello and other module uses it
i hope i help you
Related
When I install a hyperledger fabric network (as instructed on hyperledger.readthedocs.io), it gives me ability to communicate with the deployed blockchain instance. There are a few CLI commands that I can use to stop/restart the service.
I am looking for a UI based tool, that an admin user can leverage to view the activity, as well as control the different entities in the blockchain network.
Note: I have already seen Blockchain explorer but its apparently a read-only tool.
Many Thanks.
I think Hyperledger Composer is best way to access the Hyperledger Fabric Network.
It Provides UI to access full blockchain network.
You can find the tutorials here.
Also, if you want to view total blocks, transactions, peers data, then You can use Hyperledger Blockchain Explorer.
The link is here.
Hyperledger Cello is the tool which can help you to manage blockchain in an efficient way.
Using Cello, everyone can easily:
Build up a Blockchain as a Service (BaaS) platform quickly from scratch.
Provision customizable Blockchains instantly, e.g., a Hyperledger fabric network v1.0.
Maintain a pool of running blockchain networks on top of baremetals, Virtual Clouds (e.g., virtual machines, vsphere Clouds), Container clusters (e.g., Docker, Swarm, Kubernetes).
Check the system status, adjust the chain numbers, scale resources... through dashboards.
https://cello.readthedocs.io/en/latest/
enter link description here
I’m interested into the development of Blockchain Apps using Fabric and Composer.
I’ve got just one question: while Ethereum is a public blockchain so you can deploy your Smart Contract on it and use them freely, can we do the same thing with Fabric? Let me explain: Ethereum has a running Blockchain on which we can work and access, but Fabric has not, right? Should I set up an entire new blockchain network before (setting up all the nodes, giving permissions etc.)?
Thank you
Hyperledger Fabric is different to the blockchain systems you mention in it is private and permissioned. Rather than an open permissionless system that allows unknown identities to participate in the network (requiring protocols like “proof of work” to validate transactions and secure the network), the members of a Hyperledger Fabric network enroll through a trusted Membership Service Provider (MSP). Member organisations would generally set up their own Fabric infrastructure, if they're participating in the blockchain network (context provided earlier). See more on FAQ here -> http://hyperledger-fabric.readthedocs.io/en/release-1.2/Fabric-FAQ.html and understand more on key Fabric Concepts here -> http://hyperledger-fabric.readthedocs.io/en/release-1.2/key_concepts.html . As for Hyperledger Composer, that is a development framework, with tools etc to accelerate development and abstract things to a business level (ie App development using structure/validated, model driven development as a given). See more here -> https://hyperledger.github.io/composer/latest/introduction/introduction (and also see the architectural and key concept links there).
So yes, you will have a running, private blockchain network (including all of the functionality discussed in the docs) with Hyperledger Fabric.
As in Ethereum we can able to create public blockchain and then the user can able to run smart contract on it, same thing we can do in Hyperledger fabric also.
Hyperledger Fabric has the same functionality as smart contracts called as “chaincode”.
A chaincode is a program that is written to read and update the ledger state. All the business logic handled by chaincode.
For example, if a transaction created then chaincode share and update the ledger throughout the network.
About a Fabric based running blockchain we can work on it and can access it but that's only possible when someone from existing network invites you.
It is quite difficult to say you should setup an entire new blockchain network until I know your use case. Based on your use case you can setup an entire new blockchain network using fabric which will be private.
I have started to learn Hyperledger Fabric and Composer. I am able to create a simple Business Network using Composer and deploy it on Fabric, but I have a question. Let's say I have 2 BNA (instantiated on single channel) files both having same namespace (org.example) and having same participant name as well, as Customer (identifier will be org.example.Customer). Is there any way that I can access the participants created by first Business Network App in another Business Network App? Logically what I can think of is since both have been instantiated in the same channel with different chaincode and same model file, data should be cross accessible. But it isn't.
Although chaincodes share the same ledger when installed on the same channel (and as business networks are just chaincodes this applies to them also). Fabric still partitions the data that a chaincode can read/write by it's chaincode id. So when you install 2 business networks onto the same channel they will have different chaincode id's and so their data is separately partitioned.
As mentioned in the other answer (although the link is not quite correct), what you can do is make use of a feature of composer to be able to invoke another business network on the same or even different channel from the executing business network.
As the 2 business networks are on the same channel you can not only read information but you are also able to invoke transactions that can change information. (You can only read information if the business networks are on different channels).
The correct link for the tutorial is here
https://hyperledger.github.io/composer/latest/tutorials/invoke-composer-network
Unfortunately this tutorial is rather basic and only offers a glimpse of how to interact with other business networks.
Is available a tutorial about how to interact from a bna to another one.
Here the link to the official Hyperledger Composer documentation.
https://hyperledger.github.io/composer/latest/tutorials/invoke-composer-network
As I was reading about blockchain application, I came across APPII, an online verification, career management, and recruitment platform.
Just wanted to know if is it possible to build an Dapps like this in Hyperledger Composer.
Is it(Appii) a private or a public blockchain network?
in regard to Hyperledger Composer yes, its possible, as it sits atop Hyperledger Fabric as its incumbent blockchain where the ledger sits and as you know Fabric is a permissioned blockchain platform.
There is an example here -> http://www.goverticalworkshop.com/resources/how-to-create-a-decentralized-application-running-on-hyperledger-fabric-network
(it has sample links to resources it uses but I do notice that some commands (eg composer network deploy need updating, but can see similar from the docs
Sorry you'll have to ask APPII if they're using private or public blockchain or do your own research. Given that they are partnering organisations as verifying institutions/partners and interacting with joe public to upload their CV, so that its constituent claims/artifacts can be validated/verified - the use case is hybrid (it would seem).
I have been building an application in hyperledger composer.
All the tutorials I find related to hyperledger fabrics talks a lot about Orderers, Channels, Peers, Ledger etc. But none of the hyperledger composer tutorial relates the concepts of Asset, transaction or Participants to those.
For instance, hyperledger composer supports only a single channel, then how is the privacy of a transaction maintained there? Is it through the permission.acl file?
Also relating to the famous Vehicle lifecycle network.
Will each of those manufacturer be an organization(having several peers within it) in a blockchain network?
Do all the manufactures needs to host a peer(containing both the ledger and chaincode)?
Does the regulator body also need a peer?
Please help me understanding it clearly.
See here https://hyperledger.github.io/composer/latest/introduction/key-concepts for Concepts and here -> https://hyperledger.github.io/composer/latest/introduction/introduction for an Intro to Hyperledger Composer and a slidedeck on Composer concepts can be found here -> https://www.slideshare.net/MattLucas3/blockchain-composed-v207
Manufacturer will be a member organisation of the blockchain network
Its likely a Manufacturer will want to host it, or have it hosted as a major party. Its also possible that an organisation doesn't stand up any infrastructure and relies on a portal into the blockchain if it is agreed it should have an interest, by the consortium that stand up the blockchain network. Same applies for the Regulator in that respect.
Sadly, the concept of private channels is a feature of Hyperledger fabric and isn't available in the composer framework. But, to achieve the privacy of transaction that you are talking about you can use the ACL rules effectively. You can control who sees which transaction by defining rules in the acl file and applying them on the Historian record that contains all the transactions.
You must read about historian record (Will prove to be very useful while writing the acl for controlling transaction records): https://hyperledger.github.io/composer/unstable/reference/historian.html
Also, For data privatization in hyperledger composer there are certain practices and ways that will prove to be very useful. Go through this article: https://medium.com/coinmonks/implementing-data-privatization-within-hyperledger-composer-2bc99a11c344
Now, about the second part of your questions- Hyperledger composer doesn't involves all those endorsing peers, committing peers endorsing policy and such. In hyperledger composer when we create the rest server and the angular application and all the transactions are recorded from a single identity. For achieving a multi-user model for production using composer we can use the multi-user mode of the composer rest server and the authentication feature of the same. This helps in creating different identities/wallet for different users and then the transactions are recorded from those respective wallets.