madumas - Slashdot User

Comment Re:Missing technical details (Score 1) 73

by madumas on Thursday March 09, 2017 @11:20PM (#54010697) Attached to: The Promise of Blockchain Is a World Without Middlemen

Sorry for misreading your questions. The article talks about blockchains in general, it does not refer to one in particular, so it is not possible to give specific answers to your questions.

When people talk about "general purpose" blockchains, usually they have in mind Ethereum (which uses cpu-resistant POW, to make sure ASICs are not economical. Planning to transition to POS) and Hyperledger which uses PBFT. My understanding of Hyperledger is that is assumes that most nodes are acting in good faith, but I might be wrong.

Comment Re:A middle man always comes back into the picture (Score 1) 73

by madumas on Thursday March 09, 2017 @09:50PM (#54010435) Attached to: The Promise of Blockchain Is a World Without Middlemen

It's a VM, but it's not free. You need to pay the cost of CPU processing, so to be able to be 'unkillable', a virus will need to be able to generate revenues on its own, to be able to support its "life-style".

But yeah, being turing-complete is a major challenge. Ethereum sustained a major DOS attack a few months ago because some opcodes were mispriced. An attacker was able to bog down the network with a relatively small investment.

Comment Re:I call bullshit (Score 4, Informative) 73

by madumas on Thursday March 09, 2017 @09:22PM (#54010337) Attached to: The Promise of Blockchain Is a World Without Middlemen

Yup that's the biggest hurdle right now but multiple ideas are being explored. The one that I personally find the most promising is "sharding", an idea developed to allow the Ethereum blockchain to scale massively. In a nutshell, they will split the blockchain in multiple shards and allow transactions between them.

More details here: https://github.com/ethereum/wi...

Comment Re:Missing technical details (Score 1) 73

by madumas on Thursday March 09, 2017 @09:13PM (#54010295) Attached to: The Promise of Blockchain Is a World Without Middlemen

Woah that's a lot of questions. Let me try to answer the first two:

What is the "proof of work" used by the blockchain to decide which node gets to commit to the permanent blockchain record?
A complex mathematical question that takes a long time to answer. Complexity of the question is adjusted dynamically to aim for a regular block "commit" like you say. There are alternatives to PoW, like Proof Of Stake (PoS) where you "stake" an amount of money that you will lose if you cheat.

How will the blockchain handle if a pool of nodes consisting of > 50% of the computing power for proof of work decides to "double spend" or alter a blockchain record?
It happened on smaller, less popular blockchains, where the investment to hire the necessary computer power was relatively small. That's why bigger, more popular blockchains are considered more "secure". For bitcoin, that would cost hundreds of millions and you might gain at most thousands of dollars. Double-spending will be discovered a few blocks later, that don't leave you a lot of time to cash out the bitcoins.

Comment Re:A middle man always comes back into the picture (Score 1) 73

by madumas on Thursday March 09, 2017 @09:03PM (#54010277) Attached to: The Promise of Blockchain Is a World Without Middlemen

Actually, it is quite the opposite. Blockchain platforms, like Ethereum, are being built to address the re-centralization problems that you describe.

Ethereum aims to build a centralized "world-computer" with 3 main components:
- ethereum blockchain: decentralized turing-complete VM, with built-in ability to create cryptocurrencies
- swarm: decentralized storage, similar to IPFS
- whisper: decentralized messaging

The project is still in its infancy, but it's already usable. Still not 100% decentralized as it still relies on HTTP and DNS, and scaling is on the roadmap. Just to give you an idea of what this platforms makes possible, here are examples of projects already launched or in alpha:
- OasisDEX: A decentralized cryptoasset exchange
- ENS: Decentralized Naming Service, to replace DNS
- uPort: self-sovereign identity
- Everex: remittance for migrant workers

The Promise of Blockchain Is a World Without Middlemen (hbr.org) 73

Posted by BeauHD on Thursday March 09, 2017 @08:05PM from the chain-reaction dept.

dryriver writes: The Harvard Business Review has an interesting article about how Blockchain technology may bring down the cost of business transactions and enable new ways of doing things: "Consider the problem that small manufacturers have dealing with giants like Wal-Mart. To keep transaction costs and the costs of carrying each product line down, large companies generally only buy from companies that can service a substantial percentage of their customers. But if the cost of carrying a new product was tiny, a much larger number of small manufacturers might be included in the value network. Amazon carries this approach a long way, with enormous numbers of small vendors selling through the same platform, but the idea carried to its limit is eBay and Craigslist, which bring business right down to the individual level. While it's hard to imagine a Wal-Mart with the diversity of products offered by Amazon or even eBay, that is the kind of future we are moving into." "Decentralization" is the idea that a database works like a network "that's shared with everybody in the world, where anyone and anything can connect to it," writes Vinay Gupta for Harvard Business Review. "Decentralization offers the promise of nearly friction-free cooperation between members of complex networks that can add value to each other by enabling collaboration without central authorities and middle men." The proposition ultimately makes things "more efficient in unexpected ways." For example, "a 1% transaction fee may not seem like much, but down a 15-step supply chain, it adds up. [...] The decentralization that blockchain provides would change that, which could have huge possible impacts for economies in the developing world," writes Gupta.

Twitter Comes Out Swinging Against Google's Personalized Search 186

Posted by Soulskill on Wednesday January 11, 2012 @01:14AM from the social-networking-drama dept.

Meshach writes "Google's release of the new 'Search Plus Your World' feature has elicited harsh words from Twitter's general counsel (who used to work with Google). He claims that the changes will make information harder to find for users and be bad news for news publishers. Some analysts are wondering if this is a prelude to a legal battle similar to Microsoft's bundling of IE."

The REAL Reason We Use Linux 682

Posted by CmdrTaco on Saturday March 15, 2008 @03:22PM from the slow-saturday dept.

Vlad Dolezal writes "We tell people we use Linux because it's secure. Or because it's free, because it's customizable, because it has excellent community support... But all of that is just marketing BS. We tell that to non-Linux users because they wouldn't understand the REAL reason." The answer to his question probably won't surprise you.

XP/Vista IGMP Buffer Overflow — Explained 208

Posted by kdawson on Tuesday January 08, 2008 @11:18PM from the that-didn't-take-long dept.

HalvarFlake writes "With all the hoopla about the remotely exploitable, kernel-level buffer overflow discussed in today's security bulletin MS08-0001, what is the actual bug that triggers this? The bulletin doesn't give all that much information. This movie (Flash required) goes through the process of examining the 'pre-patch' version of tcpip.sys and comparing it against the 'post-patch' version of tcpip.sys. This comparison yields the actual code that causes the overflow: A mistake in the calculation of the required size in a dynamic allocation."

House Bill Won't Criminalize Free Wi-Fi Operators 540

Posted by kdawson on Thursday December 06, 2007 @10:14AM from the what-were-they-thinking dept.

Velcroman98 sends word of a bill that passed the US House of Representatives by a lopsided vote of 409 to 2. It would require everyone who runs an open Wi-Fi connection to report illegal images, including "obscene" cartoons and drawings, or be fined up to $300,000. The Securing Adolescents From Exploitation-Online (SAFE) Act was rushed through the House without any hearings or committee votes, and the version that passed on a voice vote reportedly differs substantially from the last publicly available version. CNET reports that sentiment in favor of such a bill is strong in the Senate as well. Update: 12/07 06:22 GMT by Z : As clarified in an Ars writeup, this summary is a bit off-base. The bill doesn't require WiFi owners to police anything, merely 'stiffening the penalties' for those who make no effort to report obvious child pornography.

Study Warns of Internet Brownouts By 2010 318

Posted by kdawson on Monday November 19, 2007 @08:43PM from the told-you-them-pipes-was-too-small dept.

Bergkamp10 writes "Consumer and corporate use of the Internet could overload the current capacity and lead to brown-outs in two years unless backbone providers invest billions of dollars in new infrastructure, according to a new study. A flood of new video and other Web content could overwhelm the Net by 2010 unless backbone providers invest up to US $137 billion in new capacity, more than double what service providers plan to invest, according to the study by Nemertes Research Group. In North America alone, backbone investments of $42 billion to $55 billion will be needed in the next three to five years to keep up with demand, Nemertes said. Quoting from the study: 'Our findings indicate that although core fiber and switching/routing resources will scale nicely to support virtually any conceivable user demand, Internet access infrastructure, specifically in North America, will likely cease to be adequate for supporting demand within the next three to five years.' Internet users will create 161 exabytes of new data this year."

Congress Pressures DoJ With PIRATE Part II 217

Posted by Zonk on Friday November 09, 2007 @08:45AM from the nothing-better-to-do-obviously dept.

Anonymous Pirate writes "Sen. Patrick Leahy (D-VT) and Sen. John Cornyn (R-TX) have re-introduced the 'PIRATE Act' (pdf) to Congress. According to Ars Technica, the purpose of this act is to get the DoJ to go after individual copyright infringers. It would allow the Department of Justice to bring civil lawsuits instead of criminal ones so that they would be able to prosecute copyright infringers with only a minimal burden of proof, rather than the heavier burden required for criminal prosecution." Took a long time to do a sequel; we first talked about this proposal quite some time ago.

Whose Laws Apply On the ISS? 344

Posted by CmdrTaco on Wednesday November 07, 2007 @03:13PM from the well-mine-do-of-course dept.

Hugh Pickens writes "Whose laws apply if astronauts from different countries get into a fight, make a patentable discovery, or damage equipment belonging to another country while on the International Space Station? According to the Outer Space Treaty of 1967, ratified by 98 nations, states have legal jurisdiction within spacecraft registered to them. When the space station was assembled from modules supplied by the United States, Russia, Japan and the European Space Agency (ESA), partners rejected an initial proposal that US law should prevail throughout the space station. "It was agreed that each state registers its own separate elements, which means that you now have a piece of the US annexed to a piece of Europe annexed to a piece of Japan in outer space, legally speaking," said Dr Frans von der Dunk of the International Institute of Air and Space Law at the University of Leiden. So what happens if a crime is committed in space? "If somebody performs an activity which may be considered criminal, it is in the first instance his own country which is able to exercise jurisdiction," Dr. von der Dunk added."

Breaking Open Facebook With FOSS 147

Posted by kdawson on Tuesday October 30, 2007 @06:34PM from the get-out-of-the-silo-free dept.

NewsCloud writes "Since last December, Facebook has grown from 12 to 47 million users and third-party developers have launched more than 6,000 applications with its API. While privacy advocates have been concerned about Google for the past several years, most of us are just beginning to comprehend Facebook's growing impact on who, when, what and how we connect with friends. Microsoft's recent $240 million investment in the company gives it all the capital it needs for further growth. Last August, Wired published two unusual stories describing how consumers might link together a variety of third-party services to emulate Facebook, and ultimately calling on the open-source software community to build alternatives to the service. Inspired in part by Wired, I've posted some ideas describing what would be needed for an open source architecture for social networking."

Is Web 2.0 A Bigger Threat Than Outsourcing? 331

Posted by Zonk on Tuesday October 30, 2007 @08:41AM from the need-to-change-the-shirt dept.

An anonymous reader writes "According to InformationWeek, Web 2.0 is even worse than outsourcing for IT jobs. The article talks about corporations that have laid off IT staff and replaced them with technologies like mashups and wikis that can help people get things done without involving IT. Most IT people still think Web 2.0 is an overhyped buzzword, but that might not matter: So many Web 2.0 apps are sold (or given away for free) by software-as-a-service companies like Google that people can bypass IT altogether, and IT might not even know until it's too late."

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