Walmart Requires Lettuce, Spinach Suppliers to Join Blockchain • Hacker News Board

Re: Walmart Requires Lettuce, Spinach Suppliers to Join Blockchain

#121

Post by Faaak » Wed, Sep 26, 2018, 2:21 PM UTC

pythonaut_16 wrote: post #36

tomp wrote: post #28

Earlier quoted context omitted.

I don't get that either. Absent proof-of-work (which is however terribly energetically wasteful), blockchain is just a public GIT repository where every commit is signed, no?

I agree that it's a buzzword, but at least intuitively, a signed blockchain (in the true sense that each block contains a hash of the previous block) does seem to confer some additional security over a plain database. A plain database would give you a log of events and who logged them, but security and trust resides in the database and how it's authenticated. Anyone with sufficient permissions could modify the databa…

So a git repo with signed commits ?

Re: Walmart Requires Lettuce, Spinach Suppliers to Join Blockchain

#122

Post by SkyPuncher » Wed, Sep 26, 2018, 2:21 PM UTC

bayesian_horse wrote: post #76

SkyPuncher wrote: post #27

Earlier quoted context omitted.

Watching there "Blockchain" commercial was infuriating to me. I saw absolutely no way that the "Blockchain" was solving any meaningful problem. Unless each plant can be uniquely and irrevocably tagged from the time it's planted to the time it's in my bowl, this whole thing is useless.

The very point is that you can't tag the plant from the original producer to the individual consumer all the time. For one thing, you'd need to collect a whole lot of tags and carry them on. That would be the traditional solution. The blockchains record transactions. Where for example a batch of soy beans and a batch of wheat go into a batch of animal feed. Then a few batches of animal feed go into a pig (or rather m…

> Point is: There is useful information even if certain steps can't be perfectly traced.

Yes (and no), but that's not what IBM is selling with their blockchain. They're selling trust, but only providing a digital trust solution while completely ignoring the physical and human side of trust.

> There is value in not having to connect to a central database all the time.

Problem here is IBM's blockchain is still a centrally maintained database. This literally provides any value. You still need to connect to a central database at some point.

Re: Walmart Requires Lettuce, Spinach Suppliers to Join Blockchain

#123

Post by bunderbunder » Wed, Sep 26, 2018, 2:22 PM UTC

x2398dh1 wrote: post #38

Since so many comments on this thread are so absolutely negative, I will try to play devil's advocate here. Is a given blockchain a more efficient database? Not efficient measured by percent of data stored in any given entry, which of course throughput and any other, "engineering metric," will suffer because of that. As an engineer, the idea of wasted energy, memory, space, etc., makes one cringe. Efficient from the…

I really wish I could remember where I read this so I could give proper credit --

Somewhere I read a helpful way to rephrase "blockchain" that really helps cut to the heart of the issue when you're dealing with technical questions like this: A blockchain is just an ordered series of files, each of which contains a hash of the previous one in the series.

So, when you've got someone saying, "What if we use blockchain?", just mentally substitute the suggestion as, "What if we store the data as an ordered series of files, each of which contains a hash of the previous one in the series?" Any bits of the proposed system that aren't impacted by the decision to store the data as an ordered series of files, each of which contains a hash of the previous one in the series, also don't have anything to do with whether or not it needs to involve a blockchain.

(Yes, I realize there are additional questions around trust and proof of work and whatnot that come into play when you're talking about blockchain-as-in-cryptocurrency, but, as far as I can tell, it's a rare case that proposed use cases for blockchain in business are ones where anyone even wants trustlessness. See, for example, Walmart trying to use a centralized blockchain to manage their edible leaf supply chain.)

Re: Walmart Requires Lettuce, Spinach Suppliers to Join Blockchain

#124

Post by denzil_correa » Wed, Sep 26, 2018, 2:34 PM UTC

x2398dh1 wrote: post #38

Since so many comments on this thread are so absolutely negative, I will try to play devil's advocate here. Is a given blockchain a more efficient database? Not efficient measured by percent of data stored in any given entry, which of course throughput and any other, "engineering metric," will suffer because of that. As an engineer, the idea of wasted energy, memory, space, etc., makes one cringe. Efficient from the…

> Is a given blockchain a more efficient database?

One property of a database that may not exist on blockchain is deletion of records. You can not delete "records" on blockchain due to its immutable property.

Re: Walmart Requires Lettuce, Spinach Suppliers to Join Blockchain

#125

Post by clubm8 » Wed, Sep 26, 2018, 2:35 PM UTC

duxup wrote: post #60

code4tee wrote: post #18

IBM is quietly brushing its Watson mess under the carpet and now they’re trying to focus on blockchain. However this is just as substanceless and full of marketing fluff as Watson was. There’s nothing being done here that couldn’t or shouldn’t just be handled with a traditional database. Having IBM “run it” also sort of defeats the whole decentralized aspect of blockchain technologies. You don’t need “blockchain” to…

IBM really seems stuck in their old systems / and at some level doesn't understand what to do with new systems. I was talking to someone who was using the "IBM cloud". They went to spin up some servers and etc and IBM was all "that will take a few weeks, we have to install them". At least to me "cloud" includes the ability to spin stuff up on demand.... IBM was operating it like you were ordering from a very old co-l…

>they went to spin up some servers and etc and IBM was all "that will take a few weeks, we have to install them". At least to me "cloud" includes the ability to spin stuff up on demand.... IBM was operating it like you were ordering from a very old co-location service or something.

Well, the spin up is instant, but the multiple forms and stakeholder sign offs aren't :-)

Re: Walmart Requires Lettuce, Spinach Suppliers to Join Blockchain

#126

Post by lmpostor » Wed, Sep 26, 2018, 2:35 PM UTC

SkyPuncher wrote: post #118

bayesian_horse wrote: post #65

Earlier quoted context omitted.

As I understand it, a blockchain is a decentralized database which does not require the individual instances to have perfect connectivity and perfect trust all the time. I can see why that would be something worth doing in a food chain. To trace, for example, a particular load of soy beans to a customer eating a steak, there are a couple of completely autonomous companies/sole proprietors involved. From the original…

> does not require the individual instances to have perfect connectivity and perfect trust all the time. The blockchain does not solve the trust issue in this scenario. Blockchains only work there is a verify unit entirely enclosed in the system - including the origins of any "unit" on the system. * Bitcoin/Ethereum/etc - "coins" are a completely digital concept fully enclosed by the system. "coins" are generated in…

Excellent response.

Though here is another perspective I thought of. What the usage of blockchain would allow is a chain of liability to exist among different companies in the supply chain. If you are signing off on a product, you are verifying the authenticity of the item, and if it arrives defective at the next location you assume liability. As a customer, what you would really leverage, is the incentive of every individual company to not be liable for any issues to the next company in the supply chain. You would still be required to some degree to verify the direct transaction of the item to yourself, but if ubiquitously applied, it should offer some higher level of trust simply due to the transparency offered.

If this is needed in current society or will be implemented is another question, but I think large business definitely has incentive to minimize liability through something like this.

Re: Walmart Requires Lettuce, Spinach Suppliers to Join Blockchain

#127

Post by paulsutter » Wed, Sep 26, 2018, 2:37 PM UTC

pimlottc wrote: post #111

paulsutter wrote: post #106

There are two reasons to use a blockchain: to avoid double spending in an adversarial environment, and to avoid central control of a database. This application requires neither, and this implementation accomplishes neither.

I'm aware of the latter justification, but can you elaborate further how a blockchain is more effective at preventing double spending than a centralized system?

An adversarial environment kinda rules out control by one of the adversaries (ie, whoever is running the centralized system)

Re: Walmart Requires Lettuce, Spinach Suppliers to Join Blockchain

#128

Post by bunderbunder » Wed, Sep 26, 2018, 2:38 PM UTC

denzil_correa wrote: post #124

x2398dh1 wrote: post #38

Since so many comments on this thread are so absolutely negative, I will try to play devil's advocate here. Is a given blockchain a more efficient database? Not efficient measured by percent of data stored in any given entry, which of course throughput and any other, "engineering metric," will suffer because of that. As an engineer, the idea of wasted energy, memory, space, etc., makes one cringe. Efficient from the…

> Is a given blockchain a more efficient database? One property of a database that may not exist on blockchain is deletion of records. You can not delete "records" on blockchain due to its immutable property.

Though, for the sake of argument, even in SQL databases people are increasingly moving toward append-only tables where you never physically update or delete existing records, you just insert a new one that supersedes the old one. The same approach would work for a blockchain.

Re: Walmart Requires Lettuce, Spinach Suppliers to Join Blockchain

#129

Post by theossuary » Wed, Sep 26, 2018, 2:42 PM UTC

bunderbunder wrote: post #116

bayesian_horse wrote: post #65

Earlier quoted context omitted.

As I understand it, a blockchain is a decentralized database which does not require the individual instances to have perfect connectivity and perfect trust all the time. I can see why that would be something worth doing in a food chain. To trace, for example, a particular load of soy beans to a customer eating a steak, there are a couple of completely autonomous companies/sole proprietors involved. From the original…

> As I understand it, a blockchain is a decentralized database which does not require the individual instances to have perfect connectivity and perfect trust all the time. Specifically, perfect trust in the log itself . Blockchain gives you a guard against someone trying to retroactively tamper with the log. It doesn't give you a whole lot of help with the points where data enters the log in the first place. e.g., th…

Actually it does. IBM is spearheading the Hyperledger projects, so I'd suspect they're using Fabric. Fabric allows you to run chaincode on all transactions, which has to succeed for all parties of the secure ledger before the transaction is committed to the log. I think this tech makes a lot of sense for the use case.

Plus, I'm excited to see IBM do something new, if it works we all benefit.

Re: Walmart Requires Lettuce, Spinach Suppliers to Join Blockchain

#130

Post by drb91 » Wed, Sep 26, 2018, 2:43 PM UTC

SkyPuncher wrote: post #118

bayesian_horse wrote: post #65

Earlier quoted context omitted.

As I understand it, a blockchain is a decentralized database which does not require the individual instances to have perfect connectivity and perfect trust all the time. I can see why that would be something worth doing in a food chain. To trace, for example, a particular load of soy beans to a customer eating a steak, there are a couple of completely autonomous companies/sole proprietors involved. From the original…

> does not require the individual instances to have perfect connectivity and perfect trust all the time. The blockchain does not solve the trust issue in this scenario. Blockchains only work there is a verify unit entirely enclosed in the system - including the origins of any "unit" on the system. * Bitcoin/Ethereum/etc - "coins" are a completely digital concept fully enclosed by the system. "coins" are generated in…

Well, this is still an improvement over having no information about your produce, and a blockchain would provide a reliable ledger to sue deceptive food sources.