
Walmart Requires Lettuce, Spinach Suppliers to Join Blockchain - stablemap
https://blogs.wsj.com/cio/2018/09/24/walmart-requires-lettuce-spinach-suppliers-to-join-blockchain/
======
code4tee
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 track where your produce came from. This is
just a marketing play through and though.

~~~
bayesian_horse
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 soy farmer, through feed production (maybe
multiple factories because the soy is processed and later mixed with other
ingredients), feed distributors and transporters, to the cattle farm. Again
the individual animal can change hands multiple times, for example a bull calf
can be fed soy based milk exchangers at a dairy farm where it was born, then
be sold to a farm that raises it to market (with pigs there can be three
different farmers from piglet to market maturity), then to the slaughterhouse,
the meat goes to food processors and then into a distribution channel.

Easily a dozen or two separate legal entities. I can see why it could be hard
to connect each of them to a central database reliably may be tricky.

~~~
SkyPuncher
> 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 a predictable, consensus based manner with consensus based means of exchanging their value.

* Distributed Filesharing - "files" are stored in encrypted in a verifiable manner. I have an identity (or multiple identities) on the system which I can use to verify the source. Trust does become a factor in something like Civil where credibility is attached to a trust that an author actually published something.

* Food - involves a physical good that cannot be verified by the "blockchain". I can verify that SOME item went through a certain set of checkpoints. I can possibly verify that the SAME item went through a certain set of checkpoints. I cannot however verify the authenticity of any item before entering into the system. I have to rely on a middle-man (e.g. Walmart, Kroger, Whole Foods, etc) to verify authenticity at the origin point. They also have to implement safe guards that ensure goods cannot be tampered with between checkpoints. That relies on trusting the middleman to have appropriate safeguards in place.

~~~
lmpostor
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.

~~~
SAI_Peregrinus
But since it's working with legal liability there's no need for blockchain.
That can be done through standard contracts and having companies certify that
their items are authentic. You still need such a contract with a blockchain,
all the blockchain adds is some complexity.

~~~
lmpostor
I mean the question is if the complexity is needless.

Blockchain generally forces some level of standardization or there will be
rejection, as well as being incredibly easy to audit.

In a well functioning system, there is little benefit, but I would say that a
blockchain based system elevates the floor of a functioning system due to its
nature.

~~~
njarboe
As you stated, blockchains can be quite useful in a low trust environment.
Thus currently most of its use cases are by criminals or transactions that
can't be easily adjudicated, like international money transfers. I hope that
the cryptocurrency craze is more just a standard get-rich-quick ponzi scheme
in action than a sign that the West's hard won high trust culture is changing
to a low trust one.

------
x2398dh1
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 standpoint of preventing loss of human life or preventing
sickness? Well, in the United States where likely most of us live, this is not
as big of a problem, but likely in many other countries such as China, "food
authenticity," is a problem. Let's keep in mind that Walmart has more stores
and customers in China and more problems with food than the United States by
orders of magnitude.

If I'm an actor within the food system in China which presumably has multiple
middle-men, and I want to move one product up the supply chain through
multiple, ultimately ending up on the shelves at Walmart, then I will not want
to give away my source, because I want to get preferential pricing. However if
I can convince my suppler upstream to use this tool (it doesn't matter if it's
IBM, Google, Alibaba, or some startup or whatever, it's just a tech tool), to
track and register when food was, "picked" or "harvested" then I don't have to
give information to my buyer about the source, yet the database is all,
"standardized," in terms of labeling. Keep in mind the alternative would be
some kind of bar coding system which perhaps Walmart would have to impose.
Well, I don't want my upstream partners knowing that this is going to Walmart
either, otherwise they will jack up the pricing. If everyone is using some IBM
tool, and assuming the IBM tool sees increasing adoption, then no one
(hopefully) knows where or who a particular food is going to, yet any problem
foods can be tracked back to their source by the end seller, without having to
impose multiple types of key-value pair, bar-coding database systems, which -
while technically easier to implement and run more smoothly from an
engineering standpoint, perhaps do not take the entire use case into mind,
because parties within the supply chain may be unwilling to share their source
or destination due to pricing incentives.

Mind you, I am no food systems expert, I am just trying to talk hypotheticals
here. I think the knee-jerk reaction on Hacker News within this thread is an
almost Redditian "reaping karma" approach by putting down Blockchain, because
many of us have had bad experiences working with corporate executives who have
no idea how various types of technology work, and implementing non-technology
buzzwords ends up being painful. That being said Blockchain at its heart,
stripping away the history, is just a mathematical concept, and it's a math
tool that can be used to point from one source to another. Calling it a, "mind
disease," is losing sight of that.

Typically the types of discussions on hacker news that I enjoy reading are
more angled toward how do you reverse engineer things, not just insulting an
idea without backing up one's insult.

~~~
bunderbunder
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.)

~~~
sah2ed
> A blockchain is just an ordered series of files, each of which contains a
> hash of the previous one in the series.

Mentioning the hash is an implementation detail -- it is what gives
blockchains their immutability property.

So I'd say even simpler: a blockchain is merely an append-only register that
can be used by multiple parties.

~~~
bunderbunder
It is absolutely an implementation detail.

But it's also the defining characteristic - it's the essential thing that sets
blockchains apart from all the many other ways you could create an append-only
register that can be used by multiple parties.

The fact that the hash is both an implementation detail and the defining
characteristic is exactly why, IMO, "blockchain" is an inappropriate word to
use in most business plans. Implementation details as a headline feature of
your elevator pitch is a classic characteristic of a solution in search of a
problem.

As far as I'm aware, nobody was talking about peer-to-peer supply chain
management before "blockchain" became a buzzword. Probably because you don't
need peer-to-peer when you have a natural central authority. The organization
whose supply chain it is in the first place, for example.

~~~
TheColorYellow
Supply chains aren't really owned by a single entity, right? Walmart may be
the biggest actor and driver of requirements but they don't own anything
beyond the specific services they are paying for. Its a complicated system of
actors - which is where something like a DLT or blockchain can help bring
together in a more cohesive way.

Agree with everything else you said.

------
wyldfire
Decentralized? No, it's "IBM Food Trust". So how is this any better or
different from hosting a database on IBM's server? Secured by a PoW? Doubt it.

Here's the closest I could find to technical info:

> IBM Food Trust's blockchain solution, on the other hand, is permissioned so
> invited members know exactly with whom they are transacting, similar to what
> happens between business partners today. Participants also determine what
> data is seen by whom, thereby providing information on a need-to-know basis.
> Smart contracts also run on our blockchain, allowing business logic to help
> solve disputes, automatically execute contracts, and build trust.

~~~
x2398dh1
Where does anything in this article or anywhere in the title does it say the
word, "Decentralized?" Where are you getting that from?

~~~
Slartie
If it's not intended to be a decentralized system in the first place, the
"blockchain" aspect is useless and turns from being a clever hack that allows
to generate a certain level of trust from distributed participants, thus
enabling the decentralization in the first place, to a marketing ploy that, if
not just being lip-service but actually implemented, is a huge resource hog
and severely reduces scalability and maintainability of the system without
offering any benefits whatsoever.

Because of this situation it is natural to assume that a blockchain-based
system must either have a decentralization aspect to it, or that the
architects of the system are incompetent. And we don't want to assume there's
such gross incompetence at IBM, do we? ;-)

~~~
undersuit
What if the biggest feature about using the blockchain isn't that it's an open
ledger that resists tampering from untrustworthy agents but that it has lots
of hype?

------
schiffern
Make no mistake -- this is nothing but a minimally-cloaked attack on federal
food safety regulations. The word "blockchain" is only a distraction /
misdirection.

FTA:

> Tests... have produced a more complete view of the food system than under
> current federal regulations, according to Nestlé SA, Dole Food Co., and
> other participants in the project. ["more complete" != "more
> accurate/accountable"]

> _As investigators worked_ , 210 people got sick and five died, according to
> the Centers for Disease Control and Prevention. [implying blame lies with
> the _regulatory body_ , not the industry]

> A directive for suppliers to use the Food Trust blockchain will help the
> industry create a more complete picture of the food system than is possible
> under current federal regulations, Mr. Yiannas said in an interview. [ _yet
> again_ federal regs are mentioned]

> “Today, the requirement for traceability by law is one step up and one step
> back. That doesn’t work any more,” he said. [really obvious here!]

> Early this year, _as investigators worked_ to understand an outbreak of E.
> coli linked to romaine lettuce grown in the region of Yuma, Ariz., 210
> people in 36 states got sick. Five people died, according to the Centers for
> Disease Control. [ditto blame shifting]

> Blockchain establishes authorship or ownership that experts say can’t be
> faked and eliminates costly middle layers because of its peer-to-peer
> structure. [if it _can 't be faked_, obviously there's no need for
> regulators! Garbage in, perfection out! ::eyeroll::]

It's like claiming that ledgers written in pen make the SEC obsolete.

------
absurdum
Unnecessary rubbish. The article even mentions that larger growers already
have a similar(one can assume non-blockchain) system in place. This is the
product of excited executives listening to buzzwords and the always shameless
IBM ready to play along.

~~~
MrEfficiency
Glad I asked these questions in Feburary.

Sold my alts, kept my Bitcoin.

Im seriously starting to believe in the phrase Bitcoin not Blockchain.

~~~
rocqua
Monero, zCash, Ether and EOS all do things bitcoin can't and are still
decentralized.

------
peterwwillis
Alternate solution: do not announce small foodbourne illness outbreaks.

In the article's example, 250 people got sick from a lettuce outbreak, and
everyone stopped buying lettuce, hitting the whole industry. But _5 million
people_ get sick from Norovirus alone in the US every year.

Leafy vegetables like lettuce are the most common source of food illness.
Telling people about a minor outbreak is just letting them freak out for no
good reason. We should be educating people better about foodbourne illness so
they can respond without freaking out, and so they don't get sick so damn
much. And the media should stop freaking people out.

250 people out of 350 million getting sick, and not even dying? It's a _minor
risk!_ 35,000 die in traffic every year, and these people are freaked out by
some lettuce. Take a fuckin chance, would ya please?
[https://youtu.be/X29lF43mUlo](https://youtu.be/X29lF43mUlo)

~~~
prepend
The reason only 250 get sick is because of the notification. Traffic accidents
aren’t contagious. Comparing a static risk and a dynamic risk is
inappropriate.

If lettuce is contaminated with ecoli at the source and you don’t recall/stop
people eating it, you will have much more adverse health events. Different
outbreaks have different responses and sometimes that includes notifying the
at risk population and the source of the risk. [0] (this list includes lots of
norovirus outbreaks and the response for them)

We should also be educating people about food borne illness, but this isn’t
exclusive to outbreak control.

[0] [https://www.cdc.gov/foodsafety/outbreaks/multistate-
outbreak...](https://www.cdc.gov/foodsafety/outbreaks/multistate-
outbreaks/outbreaks-list.html)

~~~
peterwwillis
Let's compare the same things, then.

 _73 million Americans_ are infected with E.coli every year and 5,000 die.
Only 5 died in this outbreak. You think that number was significantly reduced
because it was announced that there was a single small outbreak?

The outbreak was minor, but the effect on the economy and people's state of
mind was overwhelmingly more powerful. It's fine to notify an at risk
population if you can, but what do you gain if just a few less people get
sick? What do you lose when people stop supporting an entire industry?

~~~
phonon
What are you talking about?

"CDC estimates that each year STEC [Shiga toxin-producing E. coli] causes
265,000 illness, 3,600 hospitalizations and 30 deaths in the United States."

[https://www.cdc.gov/features/ecoliinfection/index.html](https://www.cdc.gov/features/ecoliinfection/index.html)

~~~
peterwwillis
Sorry, I misquoted: it's 75 million cases of food borne illness in general,
and 5,000 deaths, using older statistics from smaller population sizes.

Using your stats, this outbreak was responsible for 0.1% of e.coli illnesses
and 1/6th the deaths. But it's also 1/300,000 of the overall food poisoning
illnesses, and 0.1% of the deaths.

So it hit the lettuce industry significantly harder than normal, even though
the actual effect on health was minimal compared to the norm.

~~~
phonon
Latest data is

Estimated annual number of episodes of illnesses caused by 31 pathogens
transmitted commonly by food

Domestically acquired foodborne [1]

9,388,075 (6,641,440–12,745,709)

Deaths [2]

1,351 (712–2,268)

[1] [https://www.cdc.gov/foodborneburden/pdfs/scallan-
estimated-i...](https://www.cdc.gov/foodborneburden/pdfs/scallan-estimated-
illnesses-foodborne-pathogens.pdf)

[2] [https://www.cdc.gov/foodborneburden/pdfs/scallan-
estimated-h...](https://www.cdc.gov/foodborneburden/pdfs/scallan-estimated-
hospitalizations-deaths-foodborne-pathogens.pdf)

~~~
prepend
It’s pretty hard to compare the value lost to the lettuce industry vs the
illnesses and deaths.

The EPA values a life at $7.4M for policy purposes [0]. So 1351x7.4M is about
$10B. In 2015, the value of all US farm output was $136B. [1] So you could
argue that you’d want to save more value from lives than from market impact,
if you wanted to be purely utilitarian (that I hope no one in thread does).

But there’s a big impact from illness. I think many people underestimate the
impact of food borne disease because they are young and healthy. I’m glad you
pulled up the impact because it’s a big deal.

Hopefully as people better understand the danger, we’ll be able to avoid
reductive math where we only worry about things when they are big, and way
harder to fix.

[0] [https://www.epa.gov/environmental-economics/mortality-
risk-v...](https://www.epa.gov/environmental-economics/mortality-risk-
valuation)

[1] [https://www.ers.usda.gov/data-products/ag-and-food-
statistic...](https://www.ers.usda.gov/data-products/ag-and-food-statistics-
charting-the-essentials/ag-and-food-sectors-and-the-economy/)

------
Ua2Reemo
What does a blockchain offer in this case that submitting a line to some sort
of B2B logging API where the logs are made public (like certificate
transparency) doesn't?

~~~
tomp
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?

~~~
pythonaut_16
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 database.

A signed block chain would give you a log of events where each party in the
chain signs the new block (which includes a hash of the previous block) using
their private key. The block can then be verified using each entities public
key. To modify this system you would need to be able to breach the trust of
the private keys.

{Lettuce from Farm A on date, <>}[Signed by farm A] => {Received lettuce on
date, <Farm A block>}[Signed by shipping agent] => {Received lettuce on data,
<Shipping agent block>}[Signed by Walmart store], etc

In theory then, Walmart would have a registry of the public keys of each agent
in the chain, and upon receiving produce could verify the events of the whole
block?

~~~
FLUX-YOU
Most of the security bonuses feel anemic when it's still humans entering data
into a system to track food vs. how cryptocurrencies use blockchains to track
transactions.

But now you've also raised the technical requirements and are betting the
security on non-technical farmers and farm staff. Even if they have technical
chops since farm equipment is more complex these days, they likely don't have
security chops.

There's already 'country-of-origin' scams in international shipping, so it's
not a far stretch to apply the same concept to farming supply chains. Throw a
disposable proxy farm in front of your real farms and change the origin. When
it's human-entered information, blockchain doesn't prevent someone being
dishonest from the beginning, and it lures people into a false sense of
security because of IBM's advertising.

I guess limiting fraud to the beginning of the supply chain is a step in the
right direction though. I don't think blockchain solves chain-of-custody well
though.

~~~
pythonaut_16
I think there are two key points to making such a system work:

1\. Packaging it in such a way that it's easy to use for non-technical users.

2\. There still has to be a mechanism for establishing trust in the public
keys registered in such a system.

For one I'd imagine that farmers are doing some amount of work to go from raw
"lettuce in the ground" to "one unit of shipment". Once it's a unit of
shipment it could have an ID/Bar/QRcode generated that is then scanned with a
handheld scanner that has its own keypair. The scanners keypair would be
registered with the farm and so the farm would either explicitly sign off on
the package or implicitly have signed that scanners pair as trusted by the
farm. So a farmer and farmstaff wouldn't need any technical know how beyond
operating a scanner. Depending on the farm adding such a granular tracking
system may or may not be easy to implement.

For two, I can see two options. Walmart could verify every step of the chain
themselves and register/receive the public key for each step in the chain. (So
a farm would register with Walmart as a verified producer, a shipping company
would register, etc). Or each step of the change could make a binary decision
to trust the step before it and apply pressure down chain to resolve issues,
since theoretically each step could fabricate the entire chain before passing
it off. In this scenario, Walmart would go to the shipping company and say "E.
Coli was detected in Shipment X. We no longer want to be sourced produce from
Producer Y. The shipping company then takes this into account when sourcing
produce, or else Walmart discontinues business with them.

I think the big benefit is by having an associated public key, you can verify
the claimed identity of any agent in the chain and build trust in that agent
over time. You could keep popping up disposable proxy farms, but
Walmart/Shipping provider/X doesn't have any reason to trust your proxy farm's
shipments; you have to establish trust either directly with a buyer of your
produce, or establish trust over time as a commodity provider. As you build
trust you can probably get better prices.

I'm by no means a blockchain advocate or a supply chain manager of any kind,
just doing a thought experiment of how blockchains might be effectively
applied in such a scenario. There very well might be better solutions, but I
think at the very least a blockchain presents an interesting or novel
solution.

 __Just thinking through, you could also create a sort of "doubly linked list"
and include who custody was given to as part of each block, so a farmer is
signing a claim of who they gave their produce to. {Farm A produced unit of
Lettuce X, Given to Shipper B, <no previous>}[Farm A signed]

------
theamk
I think it is important to remember this is not any blockchain, it is IBM
Blockchain For Business. I found a great overview page:

[https://www.ibm.com/blogs/blockchain/2017/05/the-
difference-...](https://www.ibm.com/blogs/blockchain/2017/05/the-difference-
between-bitcoin-and-blockchain-for-business/)

> Consensus in a blockchain for business is not achieved through mining but
> through a process called “selective endorsement.” It is about being able to
> control exactly who verifies transactions, much in the same way that
> business happens today. [...] This is different from Bitcoin, where the
> whole network has to work to verify transactions.

> Bitcoin thrives due to anonymity. [...] On the other hand, businesses have
> KYC (know your customer) and AML (anti-money laundering) compliance
> requirements that require them to know exactly who they are dealing with.
> Participants in business networks require the polar opposite of anonymity:
> privacy.

So I actually think this is not such a bad idea. I mean, it allows IBM to take
all the money from people who want to buy blockchain, but does not produce
negative effects, like energy waste. Sure, I would call it "distributed event
sourcing database", but if it has to be renamed for marketing reasons, this is
OK too.

------
muthdra
(Image) Do I need a blockchain?

[https://i1.wp.com/potdar.info/wp-
content/uploads/2018/07/ima...](https://i1.wp.com/potdar.info/wp-
content/uploads/2018/07/image_e8795092-8d69-408a-ac77-3fcdce87ca5e20180721_1650214228857716902582941.jpg)

~~~
LambdaComplex
Eh, I think it's more like "Do you need a decentralized write-once database
where you trust none of the writers? Then yes. Otherwise, no."

~~~
hazz99
Yeah, that's a dumb slide. It's true that _most_ people don't need a
blockchain, but most is not all.

------
carbocation
Walmart requires lettuce, spinach suppliers to submit information to a
database.

~~~
ekianjo
Your version does not have the same punch as the buzzwordful headline.

------
DyslexicAtheist
_" As a tech person, the word 'blockchaing' is triggering, but the real story
here is IBM and WalMart moving more surveillance and monitoring further down
the food supply chain, to squeeze more out of farmers at the expense of
everyone but them"_

[https://twitter.com/Pinboard/status/1044926267521486848](https://twitter.com/Pinboard/status/1044926267521486848)

------
StavrosK
Why is a blockchain required for this? Why can't a single party keep this
information?

~~~
maxerickson
Probably for the marketing.

The link to the actual description is behind a register wall, but there is a
bunch of marketing gibberish at:

[https://www.ibm.com/blockchain/solutions/food-
trust](https://www.ibm.com/blockchain/solutions/food-trust)

There's no proof of work or similar and participants can limit who has access
to the data they contribute, so it basically is just a data sharing system run
by a central party.

------
itissid
Can't one solve the problem of tracking food contamination with a simple key
value store that tracks supplier id and the food batch information? Whats the
advantage of using blockchain here?

~~~
bitL
It's about tracking all steps, all parts that were used, whether all companies
involved in the processing chain had appropriate ISO certificates, if sourcing
didn't originate from sanctioned countries or countries with bad working
practices etc. in order to "select" ones that fulfill given criteria, possibly
marketing them in multiple layers with certificates (this one is pure Swiss,
cows were fed grass 100% from Glarus canton, operated 100% German machinery,
food assembled by a Dutch factory implementing ISO blahblah, so here you pay
175% price; or you can get a budget version containing traces of ground
fingers of children from Uganda forced to work in a processing factory with
high contamination of environment etc.)

~~~
undersuit
Yes but how does a blockchain do anything that a database doesn't in this
instance?

------
apo
Notice how this article never clearly states specifically _how_ a block chain
solves the supply chain problem, nor does it even clearly state the problem in
the first place.

A very common response to these block chain/supply chain stories is that "a
block chain is just a database."

But even that statement is overly optimistic.

A block chain is a log file. It keeps a record of a sequence of state changes.
All of the tamper-resistant properties we associate with Bitcoin come, not
from the log file it uses, but from the economic incentives around changing
the file.

So the choice isn't between a block chain and a database for these non-
economically incentivized use cases such as IBM's supply chain projects.
Rather, the choice is between a block chain and a dumb log file.

~~~
rstuart4133
> Notice how this article never clearly states specifically how a block chain
> solves the supply chain problem

Oh, I noticed. In fact it's the first thing I go looking for in these articles
about "blockchain solves problem X".

And then I read the words "IBM Hyperledger". I've tried to find out what
Hyperledger is, but penetrating IBM's blizzard of marketing bullshit about it
has so far proved beyond me. All I know it has some relationship to a think
called a "permissioned blockchain".

From what I can gather (as it is also surrounded by a cloud of marketing hype)
a permissioned blockchain doesn't use proof of work, proof of stake or
anything related. Nor is there a race to append the block. (Thus is it
prompted as solving bitcoin's energy "problem", and because it doesn't need
time to accumulate the proof of work it's not limited in the number of
transactions it can process). Instead a permissioned blockchain appoints (ie,
gives permission to) some miners to process the blocks. I have no idea what
happens next, but I'm guessing in practice there is only one miner who checks
the incoming transactions and assembles then into a block, signs the block
using a public key, and publishes it by appending it to the database where it
remains unchanged forever more.

To me the word blockchain doesn't just mean "append only published database".
If that was true every log file would qualify as a blockchain. It also
involves a clever set of rules for appending to that database that have one
clear goal: they ensure the log is append only by making alterations
computationally expensive.

In doing that a blockchain makes the "trust" quantifiable, eg to rewrite an
entry 24 hours old in the log you are going to have to expend roughly 100 G
Watt hours. Then by using more magic (the consistency checks aren't just
rules, they are computer programs that can include assertions on future
events, and thus control what happens in the future), the assertions can
extended into "I promise to do X in the future, and if I don't I loose Y", and
the only way to undo that promise is to expend that 100 G Watt hours.

A permissioned blockchain shares none of those properties, so to me it isn't a
blockchain name notwithstanding. What it does look like is the old fashioned
titles office - if I want to transfer my house title I have to give a notice
to the Titles Office, and when they give it their official stamp of approval
and append it to their records, and it's done. In that case the currency is
property, the transactions are record of change of ownership of that property
(which always originate with the state owning the land), the blockchain
database is the records of all changes of ownership (which happens to be
public in this case), the single miner is the Titles Office.

The amount of trust you have in the system boils down to much you trust the
Titles Office to do its job (are they easily fooled, can someone be bribed,
could a fire destroy the chain, and so on). This is not easily quantifiable.
As an example I live in Australia whose civil systems are about as strong as
you can get, yet every few years we have a new headline of someones house
being sold from under them (usually while they were on an extended overseas
holiday) due to title fraud. There is no recourse when this happens - the
transaction is as irreversible as a bitcoin transaction and the state have
legislated to ensure they are not responsible for any losses. However unlike
bitcoin, it's impossible to extend the trust you put in the Titles Office to
other applications. Or to put it another way: they are not going to look after
your Ethereum ICO's for you, whereas Ethereum could do a very good job of
looking after titles.

So it isn't a blockchain. It looks to me like IBM is selling "Titles Office"
software for other applications, given it the fancy name "Hyperledger" and
added blockchain to marketing blurb for extra pizzazz. 10 points for marketing
prowess I guess.

It does however sound like a reasonable way to track food supplies. The
currency is the food with some certifications. The transaction are changes of
ownership, the miner is someone appointed to collects the sad transactions,
stamp them as official, and append them to the log, the database is public so
everyone (including the state and consumers) can verify everyone has made the
right promises on that strawberry they are eating so they can sue there arses
off if it contains needles. And the entity doing the certification (IBM?) gets
to make a bit of money for their efforts.

------
paulsutter
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.

~~~
pimlottc
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?

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

------
adamb01
Without focusing on the relevance of whether Blockchain is required in this
situation, the thing that I find interesting is that this is Walmart and this
news source is the WSJ.

That means executives from the world's largest companies are all reading this
article and many will be having discussions with their management teams about
blockchain.

Technology relevance discussions aside, moves like this are what turn fads and
buzzwords into funded projects and business models.

And when a big company like Walmart makes a move like this, others follow ...

------
pertsix
I guess they're using hyperledger?

~~~
icebraining
Yeah, Hyperledger Fabric.

[https://www.ibm.com/blockchain/solutions/food-
trust#1225961](https://www.ibm.com/blockchain/solutions/food-trust#1225961)

------
arcticbull
I feel like I’m yelling into the wind, the only time a blockchain is it all
relevant is if you cannot trust a single party. You can trust IBM in this
case, and are, which makes this just a database but harder.

------
kelvin0
To me great business innovations needs 2 equal forces: 1) The marketing and
customer oriented drive 2) The scientific, technological and engineering side.

If you only have one of each, any success is surely fickle and will quickly
dissolve.

If one force (Marketing in this case) overwhelms the other, then of course you
have 'Blockchains' to track food. Not saying that there isn't a need for this,
but it smells funny. I'm surprised there isn't a 'Deep Neural Network' used
also to make things look even more 'cutting edge' ....

------
bayesian_horse
We need a block chain in the fridge to know who ate what.

------
perfunctory
I can only imagine how terrible it must have felt to work on this project as
an engineer. So your manager tells you 'ok, we are gonna make distributed,
blockchain enabled, smart contracts based system" and then you end up building
your run-of-the-mill centralized database app. It really saddens me that we
have to put up with this kind of BS to just make a living.

------
mathattack
I’m surprised that Walmart is wasting time on this. They are both cheap, and
very good with traditional databases.

------
hallihax
This essentially just feels like a PR push so that Walmart can claim 'better
than the competition' food regulation, without actually opening up the system
to be....regulated.

There's no wider benefit to the public from this unless the chain is publicly
verifiable, imo.

------
kristjansson
We lack a good hash function for lettuce that allows one to eat it afterwards.
This will limit the efficacy of blockchains in the supply chain space, but
perhaps not their adoption...

------
JoshuaAshton
There is no reason for a blockchain here. A database would suffice just fine.
It's not even decentralized so what's the point?

------
tomhoward
Archived/paywall-free version:

[http://archive.is/RSoqh](http://archive.is/RSoqh)

------
tCfD
Of course this was bound to happen, the entire point of a blockchain is
supposed to be that joining it is voluntary based on a set of shared values
that you wish to support by contributing resources to sustain the blockchain.
Forcing someone to join the blockchain is nothing less than forcing them into
a commercial racket, and completely renders irrelevant the fundamental value
proposition of decentralization.

------
viach
Many comments are saying here "it's just a database, you don't need blockchain
for the public events log". Private blockchain become more understandable when
you dive into the level of corruption and data manipulation happening within
big corporations. It's just much more complex to change a row in blockchain
than in good old SQL database, that's it.

------
dnautics
Can someone explain why you would want to use a block chain here and not just
a "database"?

------
zer0faith
This just goes to show how ignorant people can be when trying to solve
problems with technology.

------
kown223
the comments here remind of the dropbox thread as well, people here can be so
shortsighted.

------
ethbro
Does WSJ have an editing staff? The copy reads like it was written by a bored
intern.

------
ramoz
had some thoughts:
[https://twitter.com/rambossa/status/1044975293109358592](https://twitter.com/rambossa/status/1044975293109358592)

------
s_kilk
Will this idiotic mind-virus never die?

~~~
dsr_
Of course it will. Fads come and go. Remember when everything was going to be
CORBA? Or when all user interfaces were done in Flash?

And right now AI/ML is taking over from blockchain, and lots of it will be
written by people who don't know what a linear regression is and once heard of
p-hacking but couldn't make up an example of it.

~~~
aaaaaaaaaab
>Or when all user interfaces were done in Flash?

Or in JS.

------
docdeek
This seems like a cool, real-world use of the technology.

~~~
Hendrikto
The problem is that people don’t see a problem and go looking for solutions.

People see a technology and go looking for ways to apply it.

Sure, a blockchain _can_ be used to solve this problem. But _should_ it?
Probably not. It’s hard to find technical information but it seems like the
same could have been accomplished with an easier solution.

