Zcoin Dev Update 19 September 2017: Znodes, GUI, libzerocoin, MTP and ZEth

What’s Next in Development?
After the completion of the Zcoin core upgrade, this opens up a range of improvements that the team can now work on.

libzerocoin improvements
With the assistance of Tim Ruffing, he has identified several fixes that are required in the software library that underpins Zerocoin and Poramin has implemented them into our codebase based on 0.8. Work is being done to port these fixes over to the new core 0.13 and we intend to roll this out by the end of the month or early October. We believe this is the first major improvement to libzerocoin in a long while and represents a major step forward in providing a secure Zerocoin protocol. Our next step after implementing these fixes is to do a code cleanup and refactor of the Zerocoin code to make it easier to audit.
As our commitment to open source, we will release the source code for this that will allow other projects that are using Zerocoin to secure their own Zerocoin implementations. We hope other projects can contribute to the development of Zerocoin as well.

GUI Revamp
Besides the backend, we understand the importance of having a aesthetically pleasing graphical interface especially when it relates to the use of Zerocoin. Our next task is making the wallet easy and intuitive to use.
We also will have some commands to recover Zcoin that has been stuck in unconfirmed spends from the previous version so make sure you don’t delete your old wallets with funds. As long as you have the wallet where you did the original mints, your funds are safe.

Znodes
At the same time, work will begin on Znodes, the long awaited update that allows incentivized nodes to support the Zcoin network and makes Zcoin into a hybrid Proof of Work and Proof of Stake system. Znode owners will earn a proportion of the block rewards as an incentive to maintain a full node, keep it updated and maintain the network. A certain number of Zcoin will be required as a ‘collateral’ to start a Znode to discourage Sybil attacks. This number will be announced as we come closer to launch but we aim to achieve a balance between allowing people to participate while maintaining a decent profitability for node owners to keep them sufficiently incentivized.

Reusable Payment Codes / Stealth Addresses
We are considering between either implementing BIP47 Reusable payment codes or Stealth Addresses. The benefit of Stealth Addresses is that it can be implemented very quickly given that Poramin was actually the first developer to successfully implement it in a QT wallet in Vertcoin. However, BIP47 has certain advantages over Stealth Addresses in that it can be used in light wallets and they are not distinguishable from regular Zcoin transactions however thought has to be given to how to implement it in the UI and also development will take longer.
Currently there are only two BIP47 implementations out there being the Samourai wallet and the Dark Wallet while stealth addresses are well understood and implemented in many coins.

MTP Porting to new codebase
We will port our existing MTP code to the new 0.13 codebase so that we are ready to implement MTP as soon as we can after the researchers Alex Biryukov and Dmitry Khovratovich publish their revised paper with improvements to MTP both in the areas of security and performance. We will only be able to comment on how long this will take when extended a copy of the revised paper which is expected sometime in October.

Proof of Concept Ethereum Zerocoin mixer
Tadhg is currently well underway with coding of his smart contract for ZEth (Zerocoin mixing on Ethereum). We hope to deploy a functional proof of concept mixer for Zerocoin on Ethereum soon. We hope that this project will bring greater recognition of our project with the Ethereum community along with opening up synergies between the two currencies together with cross atomic swaps which allow decentralized conversion between Zcoin and Ethereum and vice versa.
Poramin and Riordant will be attending Devcon3 in November 1-4 and aim to have the proof of concept smart contract ready by then.

Hardware Wallet Integrations
Community members have started integrating Zcoin with Trezor and Ledger. The Bitcoin core upgrade now makes their task a lot simpler and hopefully will accelerate development here.

https://zcoin.io/zcoin-dev-update-september-2017-znodes-gui-libzerocoin-mtp-and-zeth/

We are happy to announce that Indonesia's largest exchange, bitcoin.co.id,  will be listing Zcoin with a Rupiah pairing! Deposits starting 14 September 15:00 WIB and trades starting 15 September 15:00 WIB.

Just a quick update.

I'm taking a short break today from my duties as been a bit burnt out. However...here's a dev update:

New core upgrade looks to be be almost done. We wanted to release it a few days ago but encountered some crashes.
We believe that we have isolated the problem and hope to release it in the next 1-2 days. Fingers crossed.

You can see how hard at work we are from the github: https://github.com/zcoinofficial/zcoin/commits/core_upgrade and hope to publish new binaries soon.

In other news, we have been looking at some proposals that obscures transactions from where they originate from so even those that don't use TOR will have a greater degree of privacy protection. TOR users benefit as well since it is also unclear whether the transaction came from that TOR IP address as well. Looks promising.

We also have a new dev on board Peter Shugalev who will be working with us full time in assisting us to clean up and double check our code.

We are in discussions with two marketing companies as well and they are in the midst of preparing proposals in increasing awareness of our coin and communicating our message across to a greater audience as we know our communications can be seen as technical. We genuinely believe in our project and believe once people understand the tech, they can appreciate Zcoin much more.

Our recent blog post: https://zcoin.io/zcoins-privacy-technology-compares-competition/ has received immense attention and is recommended reading for anyone who wishes to understand privacy tech a bit better.

China Fake News Sinks Bitcoin...Why Isn't It Coming Back Up? Trade vs Hold, Research - CMTV Ep43

Thank you so much to Carter Thomas for his indepth look into Zcoin $XZC and for believing in our project!

Zcoin mentioned starting at 15:00

What this means is if you only want to communicate to nodes and peers on TOR, then you can specify this.

Users in TOR blocked countries probably wouldn't want to use this or they can do this through TOR with obfs4 bridge.

We just completed our first mint and spend tx on main net with the new core

Just a few more clean up !

We've also redone our OP. Hope you like it!

Our spend transaction on new core:
https://explorer.zcoin.io/tx/9322230e3a1c80ff40bf1a172aedd0ddb745b17c00914fb8c3dffed8c1417d1c

The fastest way to get hold of updates is our Twitter as it's the most regularly updated.

https://twitter.com/zcoinofficial

For a brief overview of how different privacy blockchain mechanisms stack up (including Zerocoin as used in Zcoin), read the post I made here:

https://steemit.com/zcoin/@zcoinofficial/an-overview-of-blockchain-privacy-mechanisms-and-how-zerocoin-in-zcoin-usdxzc-not-zcash-stacks-up

https://twitter.com/zcoinofficial/status/902733399026044928



Core upgrade is still being tested to make sure it's ready for release.
The core upgrade is actually very big and addresses many of the complaints and user experience issues with Zcoin and greatly improves reliability, improves TOR support and a huge number of other things.
Remember Znodes REQUIRES the core upgrade.

Zerocoin and libzerocoin fixes/improvements coming soon too.

There's some background work we are doing on MTP. Basic CPUminer and Nvidia miners are done but still awaiting the final paper but we want to have all the basics ready to do the necessary modifications once the final paper from the MTP authors are out. We are hoping it won't be too drastic of a change and merely parameter adjustments.


https://twitter.com/zcoinofficial/status/902726845535109120

There was some debate as to whether to allow other coins to immediately take advantage of the improvements we are making to Zerocoin and we know there are a quite a few coins out there just waiting for us to release this. Hence we were thinking maybe to delay the open sourcing by a few months and this would be balanced as the academic paper detailing these fixes would allow others to be aware of the issues and just not the code to immediately implement it. These type of steps aren't unprecedented as coins such as Dash initially closed source their Dark Send feature and NEM still has its NIS infrastructure remain closed source despite commitments to open source it.

However after discussion our team remains committed to open source and the changes we do to Zerocoin will be available when the new code goes live. We remember that without Bitcoin's open source and the researchers' work in coding the initial libzerocoin, there will be no Zcoin. So no need to worry about it, the releases we make will be all open sourced and subject to public audit/scrutiny.

Some development updates:

Poramin has just pushed in our private repo the fixes needed to implement the Zerocoin improvements and fixes.
Tim Ruffing has pushed the the fixes on libzerocoin as well.
Tim is now looking through Poramin's code to ensure it works as intended and Aizensou and SN are working to integrate the Zerocoin improvements into the new core upgrade 0.13.

There will be an academic paper published as well to detail these fixes so that other Zerocoin implementations (if there are any other original implementations) can fix them independently and contribute to Zerocoin research.

Our new Zerocoin code will be open sourced in due time but may not be done immediately.

We are still weighing our options here as a lot of hard work and resources was put into this and all these fixes are backend which are not quite visible to the user but are important to improving the Zerocoin protocol and its security.

That depends on the parameters no?

Indeed they can. But it's primarily about volume.

@theymos

To clarify Zcoin ($XZC) doesn't use Zcash code in any way! So it is not a clone at all...

We use the Zerocoin protocol which isn't the same as the Zerocash protocol.

While the Zerocoin protocol and a proof of concept software library (libzerocoin) was coded by the same guys who then moved on to the Zerocash paper and Zcash project, the implementation of Zerocoin is not trivial and indeed we're the first project to implement it.

We're in the midst of also improving libzerocoin as well and should be releasing updates soon.

The Zerocash protocol used in Zcash was meant to be an improvement of the Zerocoin protocol and it does achieve
a) smaller proof sizes
b) very fast verification time
c) no need for fixed denominations
d) hides tx amounts
e) allows direct send of z-balances compared to Zerocoin which requires conversion to base coin.

So if that's the case, why are we at Zcoin bothering with the Zerocoin protocol?

a) we retain supply auditability so if coins are minted out of thin air due to a flaw or the trapdoor discovered, it is easy to detect. Zcash's setup combined with its trusted setup allows creation and sending of forged coins which cannot be detected if there's a problem.
b) trusted setup in Zerocoin is far less controversial comprising of two huge prime numbers. There is also research on removing the trusted setup for Zerocoin using Sigma protocol (https://zcoin.io/zcoin-moving-beyond-trusted-setup-in-zerocoin/).
c) Zerocoin private tx are easily created with a few seconds of computation time compared to Zcash private tx which requires a few minutes.
d) We use RSA cryptography compared to new zkSNARKs.

Note that proof sizes and verification times are something that we're actively working on. Sigma allows proof sizes to be in the 1 kb range as well. We continue to evaluate and test.

While we do agree that the Zerocash paper and its technologies are pretty amazing, we do think that pursuing active research and development into Zerocoin should be encouraged and it's thanks to Zcoin and our team that many other coins now are adopting our work and re-looking into Zerocoin.

Supply auditability in a system that allows destruction and creation of coins is pretty important especially when a trusted setup is employed. Also in encouraging anonymous tx use, a few seconds of computation time is much more palatable compared to minutes and also allows weaker devices to continue to do private tx.

I hope this clarifies any doubts you may have that Zcoin is merely a Zcash clone. The truth couldn't be any further and I hope that the OP can be updated.

If anyone wants to see how Zerocoin transactions look like on the blockchain:

Check out a sample mint transaction where 50 coins go into a blackhole.
http://explorer.zcoin.io/tx/b827e91bee75e4abae8590206b088f05f6b9c563dc56e5e71c42da9523ebcccd
https://chainz.cryptoid.info/xzc/tx.dws?b827e91bee75e4abae8590206b088f05f6b9c563dc56e5e71c42da9523ebcccd.htm

This is a sample spend transaction where 50 coins come out from the blackhole and have no linkage with its mint transaction or any history at all.
http://explorer.zcoin.io/tx/d75cd4bfae85bc278900eb4728f71eedea1dec2a16d3f18551dfcd43b413ac07
https://chainz.cryptoid.info/xzc/tx.dws?d75cd4bfae85bc278900eb4728f71eedea1dec2a16d3f18551dfcd43b413ac07.htm

The point is that the 50 coin from the Zerocoin spend transaction could have come from any of the people who minted 50 coins giving it very high anonymity.

Thanks for asking

Well personally I think there was some disappointment in the delay of MTP (which we had very good reasons for). We really wanted to have it released on time but recent academic submissions have made us decide to wait longer.
https://zcoin.io/core-upgrade-to-0-13-and-mtp-update/

In our early days we also had a lot of drama, from a questionable co-founder that has since been removed and also a hack that happened due to an understaffed dev team which are lessons we have learnt from and we have greatly expanded our capabilities and team from a single developer (Poramin) to where we are now.

https://zcoin.io/team/

There's also a lot of confusion thinking that Zcoin is a clone of Zcash due to the similar names and the further confusion between Zerocoin (which Zcoin uses) and Zerocash (which Zcash uses) or people that don't understand why Zerocoin has certain advantages over Zerocash.

In time, we are confident that Zcoin and its tech will shine It's actually promising to see that there are an increasing number of coins adopting Zerocoin or forking Zcoin for their own projects

There's a richlist that you can check though a very big stash is in the BTC38 exchange.

https://explorer.zcoin.io/richlist

typical type of distribution for a newish coin

You are right, Zcoin uses the Zerocoin protocol while Zcash uses the Zerocash protocol that are different anonymization systems. You can read more here:
https://zcoin.io/zcoin-and-zcash/

Anonymization works through Zerocoin. Check out some Zerocoin mint transactions.

Check out a sample mint transaction. As you can see 50 coins get burnt into a blackhole:

http://explorer.zcoin.io/tx/b827e91bee75e4abae8590206b088f05f6b9c563dc56e5e71c42da9523ebcccd
https://chainz.cryptoid.info/xzc/tx.dws?b827e91bee75e4abae8590206b088f05f6b9c563dc56e5e71c42da9523ebcccd.htm

This is a sample spend transaction. The 50 coins come out into a new address with no prior history nor linkage to its minting tx.
http://explorer.zcoin.io/tx/d75cd4bfae85bc278900eb4728f71eedea1dec2a16d3f18551dfcd43b413ac07
https://chainz.cryptoid.info/xzc/tx.dws?d75cd4bfae85bc278900eb4728f71eedea1dec2a16d3f18551dfcd43b413ac07.htm

As you can see the mints go into a blackhole. The spend similarly comes out from a blackhole with no transaction history attached to it.

Bootstrap?

http://znode.io/