卡尔达诺在权益证明上的研究代表了加密技术的重大进步。 乌洛波洛斯通过数学上的严谨的证明第一次为权益证明算法提供了安全的保障。 这对于旨在承载数十亿美元价值流通的加密币系统来说是极其重要的。另外，如果区块链想成为新金融系统的基础设施，它必须能够轻松处理数百万用户。权益证明的节能性，高效性的特点也为加密币系统的扩张提供了可能。乌洛波洛斯协议为卡尔达诺的一个重要组成部分，卡尔达诺是目前正在开发的第三代区块链系统。在这段视频中，Aggelos Kiayias教授对权益证明为我们作出深入的分析，他具体解释了相对工作证明， 权益证明的众多优势。
So the Ouroboros protocol is the core of the Cardano blockchain
It is the settlement layer, which basically means that users can ask the layer to see
whether the transaction has been integrated and its output has been accepted by the network.
So, the settlement layer, is one of the most critical components to a cryptocurrency,
it is possible to take a single server and implement the settlement layer as a centralized service.
While this works, it has a very significant disadvantage, it introduces a single point of failure in the system,
这固然有效 但它有一个非常显着的缺点 它在系统中带来了单点故障
so while this would provide liveness about transactions, as we say, transactions would be accepted in the system.
虽然这会提供交易的活跃性 但正如我们所说 交易可在系统中被接受
If the server is hacked, or if the server is controlled by someone who wants to censor transactions,
it will be completely at the mercy of those that control the system, of what transactions can be included or not.
So this why decentralization is so important for cryptocurrencies,
so decentralizations able to distribute the trust from a single point of failure to a set of actors that distributively or collaboratively,
will produce the same service of the settlement layer.
This actually points to a classical problem in computer science that is known as consensus.
Consensus in computer science have been studied for over 40 years,
and to introduce the problem the parties face when they want to reach a common agreement to produce the same output.
While we have a very good understanding of the problem in literature about this problem,
almost all of the solutions that have been studied before the advent of the Bitcoin protocol shared the same deficiency.
It assumed that the set of parties that are running the protocol are known,
basically there is a reliable naming infrastructure and the parties that are executing the protocol know each other.
While this made sense, for classical system in computer science
it is not compatible with the way that the internet works.
There is no reliable name infrastructure that is globally available,
so for the first time, with the bitcoin protocol, in 2009,
it became feasible to think about solving consensus without assuming pre-existing names,
for the participants that are running the protocol,
and this is very important, because it removes from the solution of the consensus problem,
it removes any assumption about what are the participants that are running the protocol.
The execution of the protocol becomes public and basically all interested parties,
are open and free to become part of the protocol execution
and contribute to the integrity of the ledger, in this way, the integrity of the system is maximized,
帮助分类账本的完整性 而这样 系统的完整性得到最大化
and it is feasible to provide a settlement that is extremely hard to be disrupted.
Nevertheless, a significant deficiency of the bitcoin protocol is tremendous energy requirement,
the protocol, in order to operate, it requires for the participants, to solve what is know as Proof of Work.
为了运行此协议 它需要参与者 解决所谓的工作证明(PoW)
This means that each one of the servers that are participating and implementing this settlement layer,
they have to solve a hard computational problem, that basically have to waste a lot of energy to prove to the other participants,
that their proposal for the next set of transactions to be processed, is the one that had to be included in the settlement layer.
This, while it provides to the protocol many of its decentralization qualities that are very desirable,
it also comes with a downside, of requiring an extremely high energy expenditure.
For that reason, it was early on discussed in the bitcoin community,
whether it is feasible to retain the decentralization qualities that are provided by the bitcoin blockchain
and remove the energy waste that comes together with the protocol.
There are many ideas that were proposed by a number of people that are thinking about this problem,
but proof of stake became the one that was the most prominent, as the most convincing way,
of removing this need for proof of work, and the energy waste that comes with it from the bitcoin blockchain.
So while proof of work is the fundamental component of the bitcoin blockchain,
by its very nature, it requires to spend energy in order to advance the protocol,
now what happens in the proof of stake case is that what the participants of the protocol do
现在 在权益证明中发生的是 协议参与者所做的事情
is instead of actually spending energy to advance the protocol,
they refer to resources they have that already exists and are recorded in the ledger.
This referral, does not require the energy expenditure, that happens with proof of work.
This is what enables proof of stake, to provide a similar type of decentralization as in the case of bitcoin
but without actually having the energy waste that comes with bitcoin or any other proof of work based protocol.
So proof of stake protocols that tries to take advantage of all the state-of-the-art cryptographic tools that are available right now,
to provide blockchain protocols that can actually scale and be more participatory,
than any other protocols that are in the distributed ledger space.
So because exactly proof of stake protocols are based on cryptographic tools, such as digital signatures, public certificates,
因为权益证明协议是基于加密工具 例如数字签名 公共凭证
it is feasible to use cryptographic protocols that provide all kinds of useful services
and build these protocols on top of proof of stake ledgers in a very natural fashion.
So in this way, proof of stake ledger can provide a type of functionality, which is quite versatile,
因此 通过这种方式 权益证明分类账本可以提供一种通用的功能
that can meet many different applications, including electronic voting, supply chain management,
可以满足许多不同的应用 包括电子投票 供应链管理
and many others that could be of potentially high value for distributed ledger applications.
翻译： Mihori ，洪嘉隆