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Tiberius Brastaviceanu

docs.erisindustries.com/permissioned_blockchains.md at master · eris-ltd/docs... - 0 views

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    "What is a Permissioned Blockchain Network?"
Tiberius Brastaviceanu

Card reader - Wikipedia, the free encyclopedia - 0 views

  • Smart card
  • There are two types of smart cards: contact and contactless. Both have an embedded microprocessor and memory. The smart card differs from the proximity card in that the microchip in the proximity card has only one function: to provide the reader with the card's identification number. The processor on the smart card has an embedded operating system and can handle multiple applications such as a cash card, a pre-paid membership card, or an access control card.
  • A contactless card does not have to touch the reader or even be taken out of a wallet or purse. Most access control systems only read serial numbers of contactless smart cards and do not utilize the available memory. Card memory may be used for storing biometric data (i.e. fingerprint template) of a user. In such case a biometric reader first reads the template on the card and then compares it to the finger (hand, eye, etc.) presented by the user. In this way biometric data of users does not have to be distributed and stored in the memory of controllers or readers, which simplifies the system and reduces memory requirements.
Tiberius Brastaviceanu

Access control - Wikipedia, the free encyclopedia - 0 views

  • The act of accessing may mean consuming, entering, or using.
  • Permission to access a resource is called authorization.
  • Locks and login credentials are two analogous mechanisms of access control.
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  • Geographical access control may be enforced by personnel (e.g., border guard, bouncer, ticket checker)
  • n alternative of access control in the strict sense (physically controlling access itself) is a system of checking authorized presence, see e.g. Ticket controller (transportation). A variant is exit control, e.g. of a shop (checkout) or a country
  • access control refers to the practice of restricting entrance to a property, a building, or a room to authorized persons
  • can be achieved by a human (a guard, bouncer, or receptionist), through mechanical means such as locks and keys, or through technological means such as access control systems like the mantrap.
  • Physical access control is a matter of who, where, and when
  • Historically, this was partially accomplished through keys and locks. When a door is locked, only someone with a key can enter through the door, depending on how the lock is configured. Mechanical locks and keys do not allow restriction of the key holder to specific times or dates. Mechanical locks and keys do not provide records of the key used on any specific door, and the keys can be easily copied or transferred to an unauthorized person. When a mechanical key is lost or the key holder is no longer authorized to use the protected area, the locks must be re-keyed.[citation needed]

    Electronic access control uses computers to solve the limitations of mechanical locks and keys. A wide range of credentials can be used to replace mechanical keys. The electronic access control system grants access based on the credential presented. When access is granted, the door is unlocked for a predetermined time and the transaction is recorded. When access is refused, the door remains locked and the attempted access is recorded. The system will also monitor the door and alarm if the door is forced open or held open too long after being unlocked

  • When a credential is presented to a reader, the reader sends the credential’s information, usually a number, to a control panel, a highly reliable processor. The control panel compares the credential's number to an access control list, grants or denies the presented request, and sends a transaction log to a database. When access is denied based on the access control list, the door remains locked.
  • Access control system operation
  • The above description illustrates a single factor transaction. Credentials can be passed around, thus subverting the access control list. For example, Alice has access rights to the server room, but Bob does not. Alice either gives Bob her credential, or Bob takes it; he now has access to the server room. To prevent this, two-factor authentication can be used. In a two factor transaction, the presented credential and a second factor are needed for access to be granted; another factor can be a PIN, a second credential, operator intervention, or a biometric input
    • There are three types (factors) of authenticating information:[2]

      • something the user knows, e.g. a password, pass-phrase or PIN
      • something the user has, such as smart card or a key fob
      • something the user is, such as fingerprint, verified by biometric measurement
  • Passwords are a common means of verifying a user's identity before access is given to information systems. In addition, a fourth factor of authentication is now recognized: someone you know, whereby another person who knows you can provide a human element of authentication in situations where systems have been set up to allow for such scenarios
  • Credential
  • A credential is a physical/tangible object, a piece of knowledge, or a facet of a person's physical being, that enables an individual access to a given physical facility or computer-based information system. Typically, credentials can be something a person knows (such as a number or PIN), something they have (such as an access badge), something they are (such as a biometric feature) or some combination of these items. This is known as multi-factor authentication. The typical credential is an access card or key-fob, and newer software can also turn users' smartphones into access devices.
  • An access control point, which can be a door, turnstile, parking gate, elevator, or other physical barrier, where granting access can be electronically controlled. Typically, the access point is a door. An electronic access control door can contain several elements. At its most basic, there is a stand-alone electric lock. The lock is unlocked by an operator with a switch. To automate this, operator intervention is replaced by a reader. The reader could be a keypad where a code is entered, it could be a card reader, or it could be a biometric reader. Readers do not usually make an access decision, but send a card number to an access control panel that verifies the number against an access list
  • monitor the door position
  • Generally only entry is controlled, and exit is uncontrolled. In cases where exit is also controlled, a second reader is used on the opposite side of the door. In cases where exit is not controlled, free exit, a device called a request-to-exit (REX) is used. Request-to-exit devices can be a push-button or a motion detector. When the button is pushed, or the motion detector detects motion at the door, the door alarm is temporarily ignored while the door is opened. Exiting a door without having to electrically unlock the door is called mechanical free egress. This is an important safety feature. In cases where the lock must be electrically unlocked on exit, the request-to-exit device also unlocks the doo
  • Access control topology
  • Access control decisions are made by comparing the credential to an access control list. This look-up can be done by a host or server, by an access control panel, or by a reader. The development of access control systems has seen a steady push of the look-up out from a central host to the edge of the system, or the reader. The predominant topology circa 2009 is hub and spoke with a control panel as the hub, and the readers as the spokes. The look-up and control functions are by the control panel. The spokes communicate through a serial connection; usually RS-485. Some manufactures are pushing the decision making to the edge by placing a controller at the door. The controllers are IP enabled, and connect to a host and database using standard networks
  • Access control readers may be classified by the functions they are able to perform
  • and forward it to a control panel.
  • Basic (non-intelligent) readers: simply read
  • Semi-intelligent readers: have all inputs and outputs necessary to control door hardware (lock, door contact, exit button), but do not make any access decisions. When a user presents a card or enters a PIN, the reader sends information to the main controller, and waits for its response. If the connection to the main controller is interrupted, such readers stop working, or function in a degraded mode. Usually semi-intelligent readers are connected to a control panel via an RS-485 bus.
  • Intelligent readers: have all inputs and outputs necessary to control door hardware; they also have memory and processing power necessary to make access decisions independently. Like semi-intelligent readers, they are connected to a control panel via an RS-485 bus. The control panel sends configuration updates, and retrieves events from the readers.
  • Systems with IP readers usually do not have traditional control panels, and readers communicate directly to a PC that acts as a host
  • a built in webservice to make it user friendly
  • Some readers may have additional features such as an LCD and function buttons for data collection purposes (i.e. clock-in/clock-out events for attendance reports), camera/speaker/microphone for intercom, and smart card read/write support
Tiberius Brastaviceanu

Mantrap (access control) - Wikipedia, the free encyclopedia - 0 views

  • A mantrap, air lock, sally port or access control vestibule is a physical security access control system comprising a small space with two sets of interlocking doors, such that the first set of doors must close before the second set opens.
Tiberius Brastaviceanu

Key (lock) - Wikipedia, the free encyclopedia - 0 views

  • Key systems
  • Individually keyed system (KD)[edit]

    With an individually keyed system, each cylinder can be opened by its unique key

  • Keyed alike (KA)[edit]

    This system allows for a number of cylinders to be operated by the same key. It is ideally suited to residential and commercial applications such as front and back doors.

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  • Common entrance suite / Maison keying (CES)[edit]

    This system is widely used in apartments, office blocks and hotels. Each apartment (for example) has its own individual key which will not open the doors to any other apartments, but will open common entrance doors and communal service areas. It is often combined with a master-keyed system in which the key is kept by the landlord.

  • Master keyed (MK)
  • A master key operates a set of several locks. Usually, there is nothing special about the key itself, but rather the locks into which it will fit.
  • A practical attack exists to create a working master key for an entire system given only access to a single master-keyed lock, its associated change key, a supply of appropriate key blanks, and the ability to cut new keys. This is described in Cryptology and Physical Security: Rights Amplification in Master-Keyed Mechanical Locks.[36] However, for systems with many levels of master keys, it may be necessary to collect information from locks in different "subsystems" in order to deduce the master key.

    Locksmiths may also determine cuts for a replacement master key, when given several different key examples from a given system.

  • Control key
  • A control key is a special key used in removable core locking systems. The control key enables a user, who has very little skill, to remove from the core, with a specific combination, and replace it with a core that has a different combination.
  • Do not duplicate key
  • A "do not duplicate" key (or DND key, for short) is one that has been stamped "do not duplicate", "duplication prohibited
  • Restricted key
  • A restricted keyblank has a keyway for which a manufacturer has set up a restricted level of sales and distribution. Restricted keys are often protected by patent, which prohibits other manufacturers from making unauthorized productions of the key blank. In many cases, customers must provide proof of ID before a locksmith will cut additional keys using restricted blanks. Some companies, such as Medeco High Security Locks, have keyways that are restricted to having keys cut in the factory only. This is done to ensure the highest amount of security. These days, many restricted keys have special in-laid features, such as magnets, different types of metal, or even small computer chips to prevent duplication.
Tiberius Brastaviceanu

Smart key - Wikipedia, the free encyclopedia - 0 views

  • Keyless Go
  • The system works by having a series of LF (low frequency 125 kHz) transmitting antennas both inside and outside the vehicle. The external antennas are located in the door handles. When the vehicle is triggered, either by pulling the handle or touching the handle, an LF signal is transmitted from the antennas to the key. The key becomes activated if it is sufficiently close and it transmits its ID back to the vehicle via RF (Radio frequency >300 MHz) to a receiver located in the vehicle. If the key has the correct ID, the PASE module unlocks the vehicle.
    • transmitting low frequency LF signals via the 125 kHz power amplifier block
    • receiving radio frequency RF signals (> 300 MHz) from the built-in ISM receiver block
    • encrypting and decrypting all relevant data signals (security)
    • communicating relevant interface signals with other electronic control units
    • microcontroller
Tiberius Brastaviceanu

Chubb detector lock - Wikipedia, the free encyclopedia - 0 views

  • A Chubb detector lock is a type of lever tumbler lock with an integral security feature, a form of relocker, which frustrates unauthorised access attempts and indicates to the lock's owner that it has been interfered with. When someone tries to pick the lock or to open it using the wrong key, the lock is designed to jam in a locked state until (depending on the lock) either a special regulator key or the original key is inserted and turned in a different direction. This alerts the owner to the fact that the lock has been tampered with.
Tiberius Brastaviceanu

Key management - Wikipedia, the free encyclopedia - 1 views

  • Key management
  • his includes dealing with the generation, exchange, storage, use, and replacement of keys.
  • Key management concerns keys at the user level, either between users or systems.
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  • This is in contrast to key scheduling; key scheduling typically refers to the internal handling of key material within the operation of a cipher.
  • it involves system policy, user training, organizational and departmental interactions, and coordination between all of these elements.
  • Public Key Infrastructure (PKI)
  • A public key infrastructure is a type of key management system that uses hierarchical digital certificates to provide authentication, and public keys to provide encryption. PKIs are used in World Wide Web traffic, commonly in the form of SSL and TLS.
Tiberius Brastaviceanu

How The Blockchain Will Transform Everything From Banking To Government To Our Identiti... - 1 views

  • The first generation of the Internet was a great tool for communicating, collaborating and connecting online, but it was not ideal for business. When you send and share information on the Internet, you’re not sending an original but a copy. That’s good for information — it means people have a printing press for information and that information becomes democratized — but if you want to send an asset, it’s a problem. If I send you $100 online, you need to be sure you have it and I don’t, and that I can’t spend the same $100 somewhere else. As a result, we need intermediaries to perform critical roles — to establish identity between two parties in a transaction, and to do all the settlement transaction logic, which includes record-keeping.
  • With blockchain, for the first time, we have a new digital medium for value where anyone can access anything of value — stocks, bonds, money, digital property, titles, deeds — and even things like identity and votes can be moved, stored and managed securely and privately. Trust is not established though a third party but with clever code and mass consensus using a network. That’s got huge implications for intermediaries and businesses and society at large
  • And also with government, as a central repository of information an entity that delivers services.
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  • There’s an opportunity to disrupt how those organizations work. Intermediaries, though they do a good job, have a few problems — they’re centralized, which makes them vulnerable to attack or failure
  • They tax the system
  • They capture data
  • They exclude billions of people from the global economy
  • internet of value
  • With blockchain, we can go from redistributing wealth to distributing value and opportunity value fairly a priori, from cradle to grave.
  • creating a true sharing economy by replacing service aggregators like Uber with distributed applications on the blockchain
  • unleashing a new age of entrepreneurship
  • build accountable governments through transparency, smart contracts and revitalized models of democracy.
  • The virtual you is owned by large intermediaries
  • This virtual you knows more about you than you do sometimes
  • So there’s a strange phenomenon from the first generation of the Internet where the most important asset class that’s been created is data —and we don’t control it or own it.
  • individuals taking back their identity through your own personal avatar
  • The financial services industry
  • antiquated
  • a complicated machine that does a simple thing
  • settlement
  • an opportunity to profoundly change the nature of the entire industry. The Starbucks transaction should be instant.
  • At the heart of it, the financial services industry moves value.
  • so this is both an existential threat to the financial services industry and an historic opportunity.
  • Banks trade on trust
  • Within the decade, every single financial asset, which is really just a contract
  • will all move to a blockchain-based format
  • In the accounting world, a lot of firms rely on costly audits to drive their profits
  • With blockchain, you could have a third entry time-stamped in a distributed ledger that could be acceptable to any relevant stakeholders from regulators to shareholders, giving you a perfect record of the truth and thus the financial health of an organization.
  • Nobel-winning economist Ronald Coase argued that firms exist because transaction costs in an open market are greater than the cost of doing things inside the boundaries of the corporation.
  • four costs — of search, coordination, contracting and establishing trust
  • Blockchains will profoundly affect all of these.
  • you can now synthesize trust on an open platform and people who’ve never met can trust each other to do certain things. So this results in a whole number of new business models
  • It turns out the Internet of Everything needs a Ledger of Everything, because a lightbulb buying power from your neighbor’s solar panel definitely won’t use banks or the Visa network
  • Right now, governments take tax revenue from corporations, individuals, licenses and so on. All of that can change. We can first of all have transparency in a radical sense because sunlight is the best disinfectant. Secondly, we can open up governments in a different sense of sharing data.
  • governments can enable self-organization to occur in society where companies, civil society organizations, NGOs, academics, foundations, and government agencies and individual citizens ought to use this data to self-organize and create what we used to call services or forms of public value. The third one has to do with the relationship between citizens and their governments.
  • There are more opportunities to create government by the people for the people
  • Electronic voting won’t be delivered by traditional server technology because it won’t be trusted by citizens
Tiberius Brastaviceanu

Beyond Blockchain: Simple Scalable Cryptocurrencies - The World of Deep Wealth - Medium - 0 views

  • I clarify the core elements of cryptocurrency and outline a different approach to designing such currencies rooted in biomimicry
  • This post outlines a completely different strategy for implementing cryptocurrencies with completely distributed chains
  • Rather than trying to make one global, anonymous, digital cash
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  • we are interested in the resilience that comes from building a rich ecosystem of interoperable currencies
  • What are the core elements of a modern cryptocurrency?
  • Digital
  • Holdings are electronic and only exist and operate by virtue of a community’s agreement about how to interpret digital bits according to rules about operation and accounting of the currency.
  • Trustless
  • don’t have to trust a 3rd party central authority
  • Decentralized
  • Specifically, access, issuance, transaction accounting, rules & policies, should be collectively visible, known, and held.
  • Cryptographic
  • This cryptographic structure is used to enable a variety of people to host the data without being able to alter it.
  • Identity
  • there must be a way to associate these bits with some kind of account, wallet, owner, or agent who can use them
  • Other things that many take for granted in blockchains may not be core but subject to decisions in design and implementation, so they can vary between implementations
  • It does not have to be stored in a synchronized global ledger
  • does not have to be money. It may be a reputation currency, or data used for identity, or naming, etc
  • Its units do not have to be cryptographic tokens or coins
  • It does not have to protect the anonymity of users, although it may
  • if you think currency is only money, and that money must be artificially scarce
  • Then you must tackle the problem of always tracking which coins exist, and which have been spent. That is one approach — the one blockchain takes.
  • You might optimize for anonymity if you think of cryptocurrency as a tool to escape governments, regulations, and taxes.
  • if you want to establish and manage membership in new kinds of commons, then identity and accountability for actions may turn out to be necessary ingredients instead of anonymity.
  • In the case of the MetaCurrency Project, we are trying to support many use cases by building tools to enable a rich ecosystem of communities and current-sees (many are non-monetary) to enhance collective intelligence at all scales.
  • Managing consensus about a shared reality is a central challenge at the heart of all distributed computing solutions.
  • If we want to democratize money by having cryptocurrencies become a significant and viable means of transacting on a daily basis, I believe we need fundamentally more scalable approaches that don’t require expensive, dedicated hardware just to participate.
  • We should not need system wide consensus for two people to do a transaction in a cryptocurrency
  • Blockchain is about managing a consensus about what was “said.” Ceptr is about distributing a consensus about how to “speak.”
  • how nature gets the job done in massively scalable systems which require coordination and consistency
  • Replicate the same processes across all nodes
  • Empower every node with full agency
  • Hold this transformed state locally and reliably
  • Establish protocols for interaction
  • Each speaker of a language carries the processes to understand sentences they hear, and generate sentences they need
  • we certainly don’t carry some kind of global ledger of everything that’s ever been said, or require consensus about what has been said
  • Language IS a communication protocol we learn by emulating the processes of usage.
  • Dictionaries try to catch up when the usage
  • there is certainly no global ledger with consensus about the state of trillions of cells. Yet, from a single zygote’s copy of DNA, our cells coordinate in a highly decentralized manner, on scales of trillions, and without the latency or bottlenecks of central control.
  • Imagine something along the lines of a Java Virtual Machine connected to a distributed version of Github
  • Every time this JVM runs a program it confirms the hash of the code it is about to execute with the hash signed into the code repository by its developers
  • This allows each node that intends to be honest to be sure that they’re running the same processes as everyone else. So when two parties want to do a transaction, and each can have confidence their own code, and the results that your code produces
  • Then you treat it as authoritative and commit it to your local cryptographically self-validating data store
  • Allowing each node to treat itself as a full authority to process transactions (or interactions via shared protocols) is exactly how you empower each node with full agency. Each node runs its copy of the signed program/processes on its own virtual machine, taking the transaction request combined with the transaction chains of the parties to the transaction. Each node can confirm their counterparty’s integrity by replaying their transactions to produce their current state, while confirming signatures and integrity of the chain
  • If both nodes are in an appropriate state which allows the current transaction, then they countersign the transaction and append to their respective chains. When you encounter a corrupted or dishonest node (as evidenced by a breach of integrity of their chain — passing through an invalid state, broken signatures, or broken links), your node can reject the transaction you were starting to process. Countersigning allows consensus at the appropriate scale of the decision (two people transacting in this case) to lock data into a tamper-proof state so it can be stored in as many parallel chains as you need.
  • When your node appends a mutually validated and signed transaction to its chain, it has updated its local state and is able to represent the integrity of its data locally. As long as each transaction (link in the chain) has valid linkages and countersignatures, we can know that it hasn’t been tampered with.
  • If you can reliably embody the state of the node in the node itself using Intrinsic Data Integrity, then all nodes can interact in parallel, independent of other interactions to maximize scalability and simultaneous processing. Either the node has the credits or it doesn’t. I don’t have to refer to a global ledger to find out, the state of the node is in the countersigned, tamper-proof chain.
  • Just like any meaningful communication, a protocol needs to be established to make sure that a transaction carries all the information needed for each node to run the processes and produce a new signed and chained state. This could be debits or credits to an account which modify the balance, or recoding courses and grades to a transcript which modify a Grade Point Average, or ratings and feedback contributing to a reputation score, and so on.
  • By distributing process at the foundation, and leveraging Intrinsic Data Integrity, our approach results in massive improvements in throughput (from parallel simultaneous independent processing), speed, latency, efficiency, and cost of hardware.
  • You also don’t need to incent people to hold their own record — they already want it.
  • Another noteworthy observation about humans, cells, and atoms, is that each has a general “container” that gets configured to a specific use.
  • Likewise, the Receptors we’ve built are a general purpose framework which can load code for different distributed applications. These Receptors are a lightweight processing container for the Ceptr Virtual Machine Host
  • Ceptr enables a developer to focus on the rules and transactions for their use case instead of building a whole framework for distributed applications.
  • how units in a currency are issued
  • Most people think that money is just money, but there are literally hundreds of decisions you can make in designing a currency to target particular needs, niches, communities or patterns of flow.
  • Blockchain cryptocurrencies are fiat currencies. They create tokens or coins from nothing
  • These coins are just “spoken into being”
  • the challenging task of
  • ensure there is no counterfeiting or double-spending
  • Blockchain cryptocurrencies are fiat currencies
  • These coins are just “spoken into being”
  • the challenging task of tracking all the coins that exist to ensure there is no counterfeiting or double-spending
  • You wouldn’t need to manage consensus about whether a cryptocoin is spent, if your system created accounts which have normal balances based on summing their transactions.
  • In a mutual credit system, units of currency are issued when a participant extends credit to another user in a standard spending transaction
  • Alice pays Bob 20 credits for a haircut. Alice’s account now has -20, and Bob’s has +20.
  • Alice spent credits she didn’t have! True
  • Managing the currency supply in a mutual credit system is about managing credit limits — how far people can spend into a negative balance
  • Notice the net number units in the system remains zero
  • One elegant approach to managing mutual credit limits is to set them based on actual demand.
  • concerns about manufacturing fake accounts to game credit limits (Sybil Attacks)
  • keep in mind there can be different classes of accounts. Easy to create, anonymous accounts may get NO credit limit
  • What if I alter my code to give myself an unlimited credit limit, then spend as much as I want? As soon as you pass the credit limit encoded in the shared agreements, the next person you transact with will discover you’re in an invalid state and refuse the transaction.
  • If two people collude to commit an illegal transaction by both hacking their code to allow a normally invalid state, the same still pattern still holds. The next person they try to transact with using untampered code will detect the problem and decline to transact.
  • Most modern community currency systems have been implemented as mutual credit,
  • Hawala is a network of merchants and businessmen, which has been operating since the middle ages, performing money transfers on an honor system and typically settling balances through merchandise instead of transferring money
  • Let’s look at building a minimum viable cryptocurrency with the hawala network as our use case
  • To minimize key management infrastructure, each hawaladar’s public key is their address or identity on the network. To join the network you get a copy of the software from another hawaladar, generate your public and private keys, and complete your personal profile (name, location, contact info, etc.). You call, fax, or email at least 10 hawaladars who know you, and give them your IP address and ask them to vouch for you.
  • Once 10 other hawaladars have vouched for you, you can start doing other transactions because the protocol encoded in every node will reject a transaction chain that doesn’t start with at least 10 vouches
  • seeding your information with those other peers so you can be found by the rest of the network.
  • As described in the Mutual Credit section, at the time of transaction each party audits the counterparty’s transaction chain.
  • Our hawala crypto-clearinghouse protocol has two categories of transactions: some used for accounting and others for routing. Accounting transactions change balances. Routing transactions maintain network integrity by recording information about hawaladar
  • Accounting Transactions create signed data that changes account balances and contains these fields:
  • The final hash of all of the above fields is used as a unique transaction ID and is what each of party signs with their private keys. Signing indicates a party has agreed to the terms of the transaction. Only transactions signed by both parties are considered valid. Nodes can verify signatures by confirming that decryption of the signature using the public key yields a result which matches the transaction ID.
  • Routing Transactions sign data that changes the peers list and contain these fields:
  • As with accounting transactions, the hash of the above fields is used as the transaction’s unique key and the basis for the cryptographic signature of both counterparties.
  • Remember, instead of making changes to account balances, routing transactions change a node’s local list of peers for finding each other and processing.
  • a distributed network of mutual trust
  • operates across national boundaries
  • everyone already keeps and trusts their own separate records
  • Hawaladars are not anonymous
  • “double-spending”
  • It would be possible for someone to hack the code on their node to “forget” their most recent transaction (drop the head of their chain), and go back to their previous version of the chain before that transaction. Then they could append a new transaction, drop it, and append again.
  • After both parties have signed the agreed upon transaction, each party submits the transaction to separate notaries. Notaries are a special class of participant who validate transactions (auditing each chain, ensuring nobody passes through an invalid state), and then they sign an outer envelope which includes the signatures of the two parties. Notaries agree to run high-availability servers which collectively manage a Distributed Hash Table (DHT) servicing requests for transaction information. As their incentive for providing this infrastructure, notaries get a small transaction fee.
  • This approach introduces a few more steps and delays to the transaction process, but because it operates on independent parallel chains, it is still orders of magnitude more efficient and decentralized than reaching consensus on entries in a global ledger
  • millions of simultaneous transactions could be getting processed by other parties and notaries with no bottlenecks.
  • There are other solutions to prevent nodes from dropping the head of their transaction chain, but the approach of having notaries serve out a DHT solves a number of common objections to completely distributed accounting. Having access to reliable lookups in a DHT provides a similar big picture view that you get from a global ledger. For example, you may want a way to look up transactions even when the parties to that transaction are offline, or to be able to see the net system balance at a particular moment in time, or identify patterns of activity in the larger system without having to collect data from everyone individually.
  • By leveraging Intrinsic Data Integrity to run numerous parallel tamper-proof chains you can enable nodes to do various P2P transactions which don’t actually require group consensus. Mutual credit is a great way to implement cryptocurrencies to run in this peered manner. Basic PKI with a DHT is enough additional infrastructure to address main vulnerabilities. You can optimize your solution architecture by reserving reserve consensus work for tasks which need to guarantee uniqueness or actually involve large scale agreement by humans or automated contracts.
  • It is not only possible, but far more scalable to build cryptocurrencies without a global ledger consensus approach or cryptographic tokens.
  •  
    Article written by Arthur Brook, founder of Metacurrency project and of Ceptr.
Tiberius Brastaviceanu

From #blockchain to #BadgeChain - Introduction | Learning Futures - 0 views

  •  
    Badges, also about trusted access.
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