
How to Create a Private Ethereum Blockchain - prabaths
https://medium.facilelogin.com/build-your-own-blockchain-b8eaeea2f891
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VMG
What's the point of a private blockchain? Couldn't you just use a more
traditional consensus algorithm when you have a closed network?

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schnevets
Total shot in the dark, but could there be a use case in Software Licensing?
Your customer agrees to host a node in your distributed network, and all
clients are able to view a digest of licenses in a format that is not solely
owned by the publisher?

Oh, and development instances, of course.

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Immortalin
Assuming that your customers don't have more nodes than you

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option_greek
Note for anyone wanting to try this out on trial account of GCP: Your instance
will be halted with a scary sounding warning email (even if you are just
running a benchmark).

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chinathrow
Why so? Can't you run any software on GCP as long as you're within the usage
limits?

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occultist_throw
Evidently for their trials, they have bots that scan the VMs and kill machines
running cryptocurrency software. Just read a bit of threads on google, reddit
about this.

Possibly, you can run it on paid machines - but why would you? They charge you
more for a machine/hour than you can make cryptocurrency/hr.

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stephengillie
If the free tier isn't funded by conversions, then it's only really valuable
as a marketing tool.

This is why hosts are often judicious with the free hosting tier - even with
address verification and capchas, 60% of the free tier is phishing hosts using
a stolen identity and credit card. About 20% are Ebay snipers running shoe-
bots, or crypto-miners, begging for bare metal for the response times or
hardware, respectively. Another 18% are technology generalists who might
cobble together a 2004-era blog hosting service, to engorge their inner nerd -
mostly harmless, might not patch something, but will never convert.

For the first 2 groups - once the credit is up (or gets flagged for
spam/phishing), the account gets flipped. The scammer uses new email and maybe
a new credit card, and migrates their activities. Darknet forums (and probably
some subreddits) have lists of providers and how to work the free tier. I
expect software to auto-balance between multiple free-tier accounts on
multiple cloud providers exists; I've debated scripting the API calls in
Powershell in a few weekends.

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pavel_lishin
What's a shoe-bot?

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stephengillie
It's an eBay bidding bot - bid on a popular product faster than humans. For
some reason, shoes were extremely popular, and I have only ever seen this type
of user target shoes, and not other products such as handbags or hats.

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chirau
Actually it's mostly on niche stores that sell limited edition items like
Yeezy Boosts, Supreme, BAPE. They even do it for clothes now. They have a
release date and time and sell out within seconds

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stephengillie
How is Etherium's latency? Would it be at all worthwhile to pursue building a
shoe-bot (or other HFT/bidding bot) on an Etherium platform? Is there a future
where users could pay more Gas to get a low-latency response?

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dreit1
For beginners I recommend truffle + testrpc as it handles everything for you
out of the box.

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coolspot
I also recommend to look at Embark. I find it more mature and well-designed
than truffle.

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dreit1
Thanks I'll need to check it out for my next project

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wslh
There is an additional important change you need to do in order to speed up
transactions for testing [https://blog.coinfabrik.com/fast-smart-contracts-
execution-e...](https://blog.coinfabrik.com/fast-smart-contracts-execution-
ethereum-private-blockchain-development-environment/)

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m3kw9
Can someone explain a few practical reasons why someone would want to build
their own. Other than to learn or to do an ICO

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gtsteve
I'm investigating this at my company so I can share a couple of ideas.

Our system is used by a series of companies to manage the performance of their
supply chain (keeping this very vague to avoid breaching NDAs).

We generate reports which show the performance. as our system sees it.
However, what if a supplier were to bribe us to change the report? I have
heard third-hand of this happening before in our industry so that's not as
crazy as it sounds.

And what if the client were to change performance criteria mid-way through a
contract? The supplier might now be showing poor performance where this is
totally unfair.

This is where a blockchain might be helpful. If we publish these reports to
the private blockchain shared between us, the customer and the supplier, the
customer can verify the blockchain at any time to prove that this has not
happen. Finally, the supplier can see if terms are updated and this is
permanently stored in the chain.

Effectively, if three parties might not trust each other, then blockchain
might be a good option to keep people honest.

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rainboiboi
That is given that the data remains true at the point of data entry into the
network. If the data entering the chain is bogus due to bribery, blockchain
won't solve the problem.

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IanCal
I think that's addressing a different problem. There are two distinct issues:

1\. Is the data correct?

2\. Has the data been changed?

For many cases, 1) is not solvable in software.

I'm not sure I really understand why 2. is something best solved with a
blockchain with a private group, but given people who have actually looked
into this when I haven't think it's relevant means I'm probably missing
something either on the requirements, difficulty to implement or features.

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hnarn
You're correct that #1 isn't solvable in software, but I have doubts that #2
is best solved with a blockchain.

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izgzhen
My post on a similar topic: [http://blog.zhenzhang.me/2017/09/12/eth-priv-
net.html](http://blog.zhenzhang.me/2017/09/12/eth-priv-net.html)

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monokh
Nice one. Have been looking everywhere for a block explorer that could be used
on local instances.

Still pretty dissapointed that etherscan isn't open source, would make local
development a hell of a lot easier.

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kanwisher
Yeah my startup is working to help devs test/deploy dApps on private
blockchains. [https://loomx.io](https://loomx.io)

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guiomie
The title should be "Run your own local Ethereum instance"

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prabaths
I guess the subtitle of the blog says that - How to Create a Private Ethereum
Blockchain from Ground-up?'

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stale2002
Oh, hey, I have a way to make private smart contracts as well.

It is called having a database and server that runs code!

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vvpan
Yes, except you are 100% in control of what goes on on your server and could
easily falsify data. The _whole_ point of cryptocurrencies is to avoid that.

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stale2002
Same with a private blockchain....

You are right. That's dumb. That's my entire point!

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josephagoss
A private blockchain spread across for example, several organizations, may be
a good vehicle for sharing a database in such a way that all parties know it
can't be falsified.

For example, you could use a different consensus algo and enable each
organization to have one vote, one mine and this would enable sharing of data
that you want to ensure hasn't been modified.

This model could connect possibly thousands of different organizations
together with a trustless setup.

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TylerE
How many more of these posts (or knockoff cryto scam coins) do we need?

