Federated Blockchains operate under the leadership of a group. As opposed to public Blockchains, they don’t allow any person with access to the Internet to participate in the process of verifying transactions. Federated Blockchains are faster (higher scalability) and provide more transaction privacy. Consortium blockchains are mostly used in the banking sector. The consensus process is controlled by a pre-selected set of nodes; for example, one might imagine a consortium of 15 financial institutions, each of which operates a node and of which 10 must sign every block in order for the block to be valid. The right to read the blockchain may be public, or restricted to the participants.
It may sound nitpicky, but I think that description leaves something to be desired in terms of presenting the “correct” mental model. First, there is no such thing as “a” bitcoin, as I am sure the author would agree. Speaking of spending or moving bitcoins perpetuates the notion of bitcoins as “things”. It might be preferable to say that you are spending or moving “units of the bitcoin protocol”. There is something similar going on here with dollars. The dollars in your bank account aren’t things either, they are units of demand or claim on a currency. The fact that printed dollars have serial numbers tends to confuse this notion. Treating something as a “thing’ which is not a thing is sometimes referred to as the reification fallacy.

Sidechains interactuando con blockchain. Blockstream explica en su paper como, a las sidechains, se les añade una nueva pieza llamada two-way peg. Two-way peg es “el conector” entre ambas cadenas y se encarga de hacer la “magia” para que los bitcoins “salten” a la otra cadena. Juntando ambas cosas obtenemos las pegged sidechain: cadenas laterales conectadas en todo momento. En la imagen puedes observar como, incluso, las sidechain pueden interactuar entre ellas. ¿Llegaremos a un escenario de blockchains interactuando con aspecto fractal?
That might sound like a problem, but it isn’t because the box can only be opened infrequently (two or three times a year), and a super-majority of miners must leave a note on the box in advance. This note states exactly where the miners intend to transfer the money. The “correct” note is automatically generated by sidechain software, and is easy to check.
@Tradle. Thanks for elaborating. I’m also thinking about these things – and hear lots of other people talk about them – but I *really* struggle with the concept. It all comes down to the table I drew in this post: https://gendal.me/2014/12/19/a-simple-model-to-make-sense-of-the-proliferation-of-distributed-ledger-smart-contract-and-cryptocurrency-projects/
Congratulations! You’ve just educated yourself on the most common advanced topics in blockchain that you’ll hear about. By understanding these concepts, you have a firmer grasp on the fundamental tradeoffs and latest research on the blockchain than most industry “experts”! Better yet, next time you hear your colleagues around the water cooler talking about state channels, the Lightning Network and Byzantine fault tolerance, not only will you know what they’re talking about but you might be able to teach them a thing or two!
Blockstream is collaborating with industry leaders to create a Bitcoin micropayment system that supports high volumes of instant tiny payments using proportional transaction fees and that operates at the speed of light. We are now developing Bitcoin Lightning prototypes and creating consensus on interoperability. Our c-lightning implementation is the go-to code and specification for enterprise Lightning Network deployments on Bitcoin, and is what powers our easy-to-use Lightning Charge HTTP Rest API.
Note: This is also a pioneering effort towards increased adoption of smart contracts because while the traditional contracts have been around for a long time, smart contracts are relatively new, and there are gaps in how they are structured. If the smart contracts have the necessary legal expressions then that could serve as a template to bridge this gap in future.
The consensus mechanism involves ascertaining transaction validity and uniqueness. Smart contracts address the validity portion. To ensure uniqueness, the protocol program in Corda checks whether any other transaction has used any of the input states of this transaction. If no other transaction has used any of the input states, that this transaction is unique.

@gendal, good question. Think of the identity hash as a bitcoin address, it is indeed public. So to assert anything with this identity you need to sign the object you are creating or changing with the identity’s private key. Specifically it is a private key that corresponds to a public key that you published in your identity’s object (json). The signature is not placed on the bitcoin transaction, as OP_RETURN has only 40 bytes. The signature is added to a [json] object that is modified with this identity. If you see any fault with this, please let me know.
Private and Public Blockchain occurs when the financial enterprises start to explore the various blocks of the Blockchain technology. These two Blockchains are coming up with business oriented models as to obtain the difference between the two. The private blockchain generates at a lower cost and faster speed than the public blockchain. In the previous years, the blockchain has grown to become an interesting subject globally. It is becoming an integrated part in the financial sectors all over the digital world.

If you want a deeper look at Proof of Stake check out our detailed POS post. In short, while Proof of Work is an effective mechanism to secure the blockchain and provides a trustless consensus paradigm, it’s extremely energy intensive because of all the computing power required to solve hash problems. Also, while it was meant to be decentralized, it’s actually becoming more centralized as miners consolidate and massive mining setups eat up larger shares of winning blocks.
This list is not exhaustive. There are plenty of public blockchains, and they are actively adopted by such industries as FinTech, gaming, logistics, and beyond. However, it not always makes sense to move certain processes and businesses to the public network as the latter are characterized by comparatively low speed of transactions execution and high costs. Indeed, every transaction requires a consensus of the entire network. Unfortunately, it takes time and resources.
When you send Bitcoins somewhere, you lay down the challenge for the next owner. Usually, you’ll simply specify that they need to know the public and private keypair that correspond to the Bitcoin address the coins were sent to. But it can be more complicated than that. In the general case, you don’t even know who the next owner is… it’s just whoever can satisfy the condition.

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Note: Some would argue that such a system cannot be defined as a blockchain. Also, Blockchain is still in it’s early stages. It is unclear how the technology will pan out and will be adopted. Many argue that private or federated Blockchains might suffer the fate of Intranets in the 1990’s, when private companies built their own private LANs or WANs instead of using the public Internet and all the services, but has more or less become obsolete especially with the advent of SAAS in the Web2.
So if you want to create a more secure Sidechain, we would seriously need to have a look at incentivizing miners in other ways. These could include things such as the Sidechain raising outside funding from investors in order to pay the miners. Staggering mining award so miners have an incentive to keep mining as they will be paid later on rather than at the time or the Sidechain could issue its own mining award on top of the already existing transaction fees and essentially just become an Altcoin.
Looking for a top private blockchain open source? Here is a list of private blockchain development companies with client reviews and ratings. Private blockchain network on contrary to public and permission blockchain can be run and utilized by one organization only. Additionally, private blockchain platform organizes distinctive components of the technology in order to serve different applications. By prioritizing productivity over the secrecy, permanence, and transparency, private blockchain open source adheres to the qualities normally connected with the technology. The scope of uses for private blockchain might be narrow yet its power to enhance processes are no less important. GoodFirms has thus created a list of top private blockchain companies below:
Mastercoin and Counterparty are embedded consensus protocols (or meta-protocols) that use the blockchain to store their transactional data. Bitcoin devs, except Peter Todd who was hired by both teams to help them find a proper solution, are very unhappy, to say mildly, about storing the data on the blockchain. Heated discussions on this topic go on for hundreds of pages on bitcointalk and Mastercoin github issue. Mining pools like Eligius started censoring Mastercoin transactions (not sure if they are continuing with this practice right now, but the operators of this pool are adamant that data do not belong to the blockchain).
The sole distinction between public and private blockchain is related to who is allowed to participate in the network, execute the consensus protocol and maintain the shared ledger. A public blockchain network is completely open and anyone can join and participate in the network. The network typically has an incentivizing mechanism to encourage more participants to join the network. Bitcoin is one of the largest public blockchain networks in production today.