Live data from Hacker News

Show HN: Very basic blockchain-free cryptocurrency PoC in Python

github.com

21–30 of 72 posts

Re: Show HN: Very basic blockchain-free cryptocurrency PoC in Python

#21
post #2

Are there any blockchain-free cryptocurrencies currently on any exchange?

Stellar Lumen

Stellar has nice properties, like a decentralised exchange built into the platform and native integration with existing financial institutions/other cryptocurrencies through anchors.

But I would not say it's blockchain-free. They close a "block" every 5 seconds. Depends on what you consider a block. They use boring stuff like PostgreSQL to store the data instead of reinventing everything.

Re: Show HN: Very basic blockchain-free cryptocurrency PoC in Python

#22
post #6

Yeah, I'm done with this "scientific" tone, this PDF thing and so on. What is in this paper that couldn't be posted as HTML in a web page? How is PDF better compared to that?

This one is not an ICO-Whitepaper. But I get where you are coming from here.

Re: Show HN: Very basic blockchain-free cryptocurrency PoC in Python

#23

So this is basically a blockchain, but with transactions instead of blocks, and diverging-then-converging graph instead of a linear sequence of blocks (like a real family graph instead of just one-parent-one-child families common in blockchains). Looks nice, what are the problems with the approach? (the paper only lists the benefits).

can this handle a trivial Sybil attack? That seems to be the drawback of a graph or DAG-based approach. -ledger scientist

Re: Show HN: Very basic blockchain-free cryptocurrency PoC in Python

#24
post #19

Earlier quoted context omitted.

IOTA: https://coinmarketcap.com/currencies/iota/ Here's the related white paper: https://iota.org/IOTA_Whitepaper.pdf Website is here: https://iota.org

Be warned about IOTA though, it still is not decentralized, see https://medium.com/@ercwl/iota-is-centralized-6289246e7b4d and the reaction of devs/foundation-members to that article, does resemble the reaction when somebody has something to hide. And https://www.reddit.com/r/Iota/comments/6jzfak/whats_wrong_wi... and some others, but also the official channels are moderated/censored. Seems to be more promise, hype a…

The problem comes down to this; at the current stage, an attacker could very easily amass 33% of the hashpower of the network, because hashing only happens at the instants when new transactions are being added to the tree, and is completed in a second using a normal laptop. I was unable to find any information on how IOTA resolves this seemingly disturbing security issue on their website or in their whitepaper, but I did find the following information in two non-affiliated blogs (1, 2) after a lot of searching:

> Milestones: Milestone is a special transaction issued by a special node called Coordinator. The Coordinator is run by Iota Foundation, its main purpose is to protect the network until it grows strong enough to sustain against a large scale attack from those who own GPUs. Milestones set general direction for the tangle growth and do some kind of checkpointing. Transactions (in)directly referenced by milestones are considered as confirmed.

This means that IOTA in its current form does not provide any censorship resistance, since the path of the tree is centrally directed through a Coordinator node run by the IOTA Foundation. As such, IOTA is no more decentralized than an Apache Kafka cluster, or Ripple and their Unique Node List. I would argue that this is crucial information a user needs to know, yet I have no idea how the average person is intended to learn about this, since it’s nowhere to be found in the IOTA whitepaper or on their website. (EDIT: Since this article was written, IOTA published a post regarding this matter https://blog.iota.org/the-transparency-compendium-26aa5bb8e2.... I responded to their post https://medium.com/@ercwl/hello-david-b77bbc62c457 )

Re: Show HN: Very basic blockchain-free cryptocurrency PoC in Python

#25
post #19

Earlier quoted context omitted.

IOTA: https://coinmarketcap.com/currencies/iota/ Here's the related white paper: https://iota.org/IOTA_Whitepaper.pdf Website is here: https://iota.org

Be warned about IOTA though, it still is not decentralized, see https://medium.com/@ercwl/iota-is-centralized-6289246e7b4d and the reaction of devs/foundation-members to that article, does resemble the reaction when somebody has something to hide. And https://www.reddit.com/r/Iota/comments/6jzfak/whats_wrong_wi... and some others, but also the official channels are moderated/censored. Seems to be more promise, hype a…

Even disregarding any flaws, I'd still consider it a blockchain - just one where each block only holds a single transaction.

Re: Show HN: Very basic blockchain-free cryptocurrency PoC in Python

#26

So this is basically a blockchain, but with transactions instead of blocks, and diverging-then-converging graph instead of a linear sequence of blocks (like a real family graph instead of just one-parent-one-child families common in blockchains). Looks nice, what are the problems with the approach? (the paper only lists the benefits).

[deleted]

Re: Show HN: Very basic blockchain-free cryptocurrency PoC in Python

#28
post #19

Earlier quoted context omitted.

Be warned about IOTA though, it still is not decentralized, see https://medium.com/@ercwl/iota-is-centralized-6289246e7b4d and the reaction of devs/foundation-members to that article, does resemble the reaction when somebody has something to hide. And https://www.reddit.com/r/Iota/comments/6jzfak/whats_wrong_wi... and some others, but also the official channels are moderated/censored. Seems to be more promise, hype a…

Even disregarding any flaws, I'd still consider it a blockchain - just one where each block only holds a single transaction.

Yes.

Having said that, the positives about IOTA;

They seem to have developed their own hashing function, of the sponge family, called Curl - and are actually using the Westernelitz (oh jesus spelling, more space-efficient Lamport) signature scheme - it is a method of constructing a digital signature only from hash functions. Cool.

Re: Show HN: Very basic blockchain-free cryptocurrency PoC in Python

#29
post #19

Earlier quoted context omitted.

Be warned about IOTA though, it still is not decentralized, see https://medium.com/@ercwl/iota-is-centralized-6289246e7b4d and the reaction of devs/foundation-members to that article, does resemble the reaction when somebody has something to hide. And https://www.reddit.com/r/Iota/comments/6jzfak/whats_wrong_wi... and some others, but also the official channels are moderated/censored. Seems to be more promise, hype a…

Even disregarding any flaws, I'd still consider it a blockchain - just one where each block only holds a single transaction.

Specifically is a blockDAG (Directed Acyclic Graph), but the term Blockchain is often used to describe the entire set of protocols.

Re: Show HN: Very basic blockchain-free cryptocurrency PoC in Python

#30
post #11

Earlier quoted context omitted.

maidsafe edit: I thought Ripple and Stellar had blockchains?

They have "ledgers". Each ledger is based on the previous ledger, but the previous ones are discarded as soon as the next reaches a state of consensus. How does MaidSafe work, by the way?

> How does MaidSafe work, by the way?

It consumes your $$$, and emissions promises that one day it'll become "a new shiny replacement of the Internet".

Post reply on HN