Author

Topic: [ANN][XMY] Myriad | Multi-Algo, Fair, Secure - page 273. (Read 850070 times)

sr. member
Activity: 448
Merit: 250
Can the efficiency of the Myriad code to keep each algorithm getting 1/5 blocks on average be measured by looking at this pie chart?

(image)

I was wondering why Skein is deviating so low and if this means there is room for improvement in the design on the coin that we can test on a testnet or something? I'm assuming we want to tend towards 20% for each and if Skein keeps dropping to 19.4, then 19.3, etc., we can be alerted that something is wrong?

That is from the whole blockchain. Ignore the earlier parts before things settled down, and instead look at figures for a short recent period (e.g. the last 24 hours, or 2880 blocks). One standard deviation each way would be 19.25%-20.75%. Two standard deviations each way would be 18.5%-21.5%.

You might even find that Skein has got more of its fair share of blocks in the last few days.

You should also expect a very slight preference towards the algorithms with high numerical difficulties (in decreasing order: SHA, Skein, Groestl, Qubit, Scrypt), for the reasons outlined recently.



Good explanation, thank you very much.
sr. member
Activity: 378
Merit: 250
Can the efficiency of the Myriad code to keep each algorithm getting 1/5 blocks on average be measured by looking at this pie chart?

(image)

I was wondering why Skein is deviating so low and if this means there is room for improvement in the design on the coin that we can test on a testnet or something? I'm assuming we want to tend towards 20% for each and if Skein keeps dropping to 19.4, then 19.3, etc., we can be alerted that something is wrong?

That is from the whole blockchain. Ignore the earlier parts before things settled down, and instead look at figures for a short recent period (e.g. the last 24 hours, or 2880 blocks). One standard deviation each way would be 19.25%-20.75%. Two standard deviations each way would be 18.5%-21.5%.

You might even find that Skein has got more of its fair share of blocks in the last few days.

You should also expect a very slight preference towards the algorithms with high numerical difficulties (in decreasing order: SHA, Skein, Groestl, Qubit, Scrypt), for the reasons outlined recently.

sr. member
Activity: 448
Merit: 250
Wow... what is with the high difficulty on groestl??

Looks to be about just as high as Skein based on the coins per scrypt mh
newbie
Activity: 30
Merit: 0
Wow... what is with the high difficulty on groestl??
member
Activity: 91
Merit: 10
I just made a request on cryptsy ... hope we will have the attention we deserve Smiley

https://cryptsy.freshdesk.com/support/discussions/topics/4000272159
sr. member
Activity: 448
Merit: 250
Can the efficiency of the Myriad code to keep each algorithm getting 1/5 blocks on average be measured by looking at this pie chart?



I was wondering why Skein is deviating so low and if this means there is room for improvement in the design on the coin that we can test on a testnet or something? I'm assuming we want to tend towards 20% for each and if Skein keeps dropping to 19.4, then 19.3, etc., we can be alerted that something is wrong?
sr. member
Activity: 448
Merit: 250
Check these out! From @Crypto_Mike on Twitter





Not sure if people saw this or not. Bumping it.
sr. member
Activity: 448
Merit: 250
Community Bounty Drive - Updated 4/3 (11:35pm CT) - Donate to the Bounties that Interest You the Most


If anyone has more ideas for bounties I can start making unique wallet addresses for them. Just list bounty ideas below and we can start donating to them!

Benefits:

MyriadCoin community can donate to projects/utilities they would like to see created the most.
MyriadCoin community members looking to fulfill bounties can see which ones offer the most coins (i.e. highest demand).

EDIT: Should we add a bounty for getting the damn stratum patches implemented so users aren't faking shares? Don't other coins have these stratum issues resolved?
member
Activity: 133
Merit: 10
my rig performance with GROESTL 
  5970 -  (11.30 + 11.30 )   =   22.6 Mh/s
  5870 -  clock- 1300 & 900 =   12.7 Mh/s
  5870 -  clock- 1300 & 900 =   12.7 Mh/s

Total Power (motherboard+cpu+External fan 60W) consumption by this rig   = 550 W

* 5XX card Gives Better Performance with GROESTL 
 
* R9 280 and R9 290 Will give Better Performance with Skein Tongue


What settings do you recommend for a 290 (both groestl and skein)?
full member
Activity: 157
Merit: 100
my rig performance with GROESTL 
  5970 -  (11.30 + 11.30 )   =   22.6 Mh/s
  5870 -  clock- 1300 & 900 =   12.7 Mh/s
  5870 -  clock- 1300 & 900 =   12.7 Mh/s

Total Power (motherboard+cpu+External fan 60W) consumption by this rig   = 550 W

* 5XX card Gives Better Performance with GROESTL 
 
* R9 280 and R9 290 Will give Better Performance with Skein Tongue
sr. member
Activity: 448
Merit: 250
It also isn't clear to me how a node calculates the best chain. If it is cumulative difficulty, without any normalisation, then what is to stop someone reversing a sequence of low difficulty blocks (e.g. Scrypt or Qubit ones, currently) by means of a single high difficulty block (SHA256D, currently)?
The SHA difficulty is independent from the other algos, so a high difficulty SHA block will not overwrite a low difficulty Scrypt block for example.

Just in the last hour or so I've seen a chain of five non-SHA256D blocks (112715-112719) erased by a single SHA256D block (112715):

[code edited out]

How should this happen if they are truly independent?

 

anyone want to give this a technical explanation.. maybe a simple explanation too Smiley

Dev is only one that can atm

This is general block reorg (also known as a chain of orphans) it happens with a block time of 30 seconds. hell even with the 10 min block time of bitcoin it happens. In myriadcoin every algo has equal standing as each has an equal score. You can see in many POS/POW coins. POS orphans POW as POS has a higher score than its POW counterpart.

Ahmed

exactly! the coin is broken because a single SHA block can force a reorganization and orphan many blocks from other algos. This allows for easy double spending with minimal hashrate. Just mine SHA from the last SHA block ignoring blocks from other algos. When you mine your new SHA block, all the others will be orphaned. If there are enough to confirm a transaction (which is very likely), you can double spend.
But it can be fixed using normalization. Scrypt is about 1024 times SHA. You'd have to calculate the relative weight for other algos.

dev: you can contact me if you need help fixing this, I have experience with alt PoWs - I'm the developer of Riecoin (new primes PoW - currently cpu only)

Someone mentioned a bounty for a technical study on 51% attacks. Is that real? where can I learn about this bounty? what do you need exactly?
Besides fixing this "high diff algo reorganization attack", I have some ideas for preventing 51% attacks on a coin like this.

regards,
gatra

I started the bounty. We could really use someone to write a technical analysis of Myriad's security features with the 5 algo system. It can be as long as you like but it should be written knowing that it will be passed around and read by other smart people who can comment and provide feedback and even offer more ideas to make Myriad's blockchain even more secure.
sr. member
Activity: 378
Merit: 250
exactly! the coin is broken because a single SHA block can force a reorganization and orphan many blocks from other algos. This allows for easy double spending with minimal hashrate. Just mine SHA from the last SHA block ignoring blocks from other algos. When you mine your new SHA block, all the others will be orphaned. If there are enough to confirm a transaction (which is very likely), you can double spend.
But it can be fixed using normalization. Scrypt is about 1024 times SHA. You'd have to calculate the relative weight for other algos.
1 thing is confusing me though. how can a person ignore blocks? ur forgetting that theres over 30 TH on the myriad network. it would take some real sha256 power to do any kind of attacks even on the sha algorithm

It seems to be quite simple. Just modify your own node's code to ignore the blocks since the most recent SHA block. You could still include all the transactions from them into your own block, so you get the fees.
sr. member
Activity: 448
Merit: 250
I have release the p2pool source code to setup a Myriadcoin qubit node on github:

https://github.com/linked67/p2pool-myrq

Let's start the revolution and make as many nodes as you wish, it's good for the network Smiley
Donations (myr) are welcome: MUHNPJvXCjCnQPeDFX2FnzWNN8C5tw9wak

PS: Don't forget to set the qubit algo in myriadcoin.conf

+2000 myr tip for you kind sir.

I'll match that tip right now. Smiley
sr. member
Activity: 378
Merit: 250
exactly! the coin is broken because a single SHA block can force a reorganization and orphan many blocks from other algos. This allows for easy double spending with minimal hashrate. Just mine SHA from the last SHA block ignoring blocks from other algos. When you mine your new SHA block, all the others will be orphaned. If there are enough to confirm a transaction (which is very likely), you can double spend.
But it can be fixed using normalization. Scrypt is about 1024 times SHA. You'd have to calculate the relative weight for other algos.

an idea to prevent panic:
there's an easy workaround (until a new client is released): when waiting for confirmations, wait for X blocks with SHA (the one with highest difficulty by far) instead of just waiting for X blocks.
So if you currently wait for 6 blocks, wait instead for 30 blocks and you should be safe ( 6 blocks  * 5 algos = 30 blocks ). This would give you the same expected security in average.

I agree with your analysis. Although I think a double spend attack isn't quite so simple: you don't know when the right circumstances are going to arise (i.e. several non-SHA blocks in a row, followed by an SHA block that you yourself mine), and you need to have sent your own transaction at or near the start of this non-SHA sequence. Still, implementing difficulty normalisation in total chain work should be considered a priority in this coin.

Regarding increasing the number of confirmations you wait for: In 30 blocks, the chance of there being 6 (or more) SHA blocks would be around 57%; you would need to wait longer to be sure of at least 6 SHA blocks. But I doubt there is a need to be so cautious; it should be enough to wait for at least 1-2 SHA blocks (minimum 6 blocks total).
legendary
Activity: 1386
Merit: 1023
sold all my black coin and went into myriad..
I think we will be at 2k very soon..

In time we will pass that.

Why be in Blackcoin which is already at 2.5 million market cap when you can be in MYR and get the ride from 300k-2.5 million over the coming days?

A wise choice.
hero member
Activity: 812
Merit: 1000
...



I have a rig with 3 R9 280X, MSI P67A-G45 (bios flashed for ivy bridge support), intel G2030, 4 Go, Seasonic P1000.
Measured at the wall, taking off 80W for motherboard+CPU+RAM+HD and dividing by 3, I get for one GPU

Groestl : 100 W
Qubit   : 115 W
Skein   : 175 W
Scrypt : 240 W

Gpu core clock 1100
Memclock from 1000 to 1500 depending on algo
1.150 V






Excellent! On par with my temp measurements...thanks.
sr. member
Activity: 336
Merit: 254
CoinMine.pw
You can mine Myriad Coin (SCRYPT) at www.CoinMine.pw - the best place to park your workers! Roll Eyes

  • 40 coins to mine from one account!
  • Unique functions
  • Easy switch worker from web interface without reconnects and stales!
  • Almost 0% reject rate !
  • Switch and monitor workers with API !
  • Check balances and withdraw funds with API !
  • EU and USA stratum nodes !
  • Auto switch workers with personal Coin Sets and Coin's Difficulty range for every Worker
  • USD, LTC, BTC rates for all mined coins!
  • Profitability calculator for LTC, USD for all coins!
  • Really FAST and clean interface.
  • Self-written server software optimized for maximum performance!
  • Cool and impressive functions adds almost every day!

And off course standard:

  • Dedicated Xeon Server
  • SSL support
  • SSD HDD RAID
  • Several 1Gbit Europe Uplinks
  • DDOS Protection
  • 99.9% Uptime since launch
  • IRC and E-mail support!
  • Stratum
  • VARDIFF
  • PPL(10MIN)S Payout
  • Manual payouts without minimum
  • Auto Payouts every 5 minutes
sr. member
Activity: 322
Merit: 250
My P2pool should be OK now. Around 50Mh/s on it and estimated 3h to find a block.

You are all welcome on my powerful server Smiley

http://p2poolcoin.com:5567/static/

What algorithm?

Qubit, it's a qubit p2pool, the first !

I have some spike above 150Mh/s now. Join the pool, no need to register, just put your wallet address as username (-u wallet) and what you want in password (-p x).

I have no idea how to set up the qubit miner Sad could anyone post a little guide or refer me to somewhere where i could find one?
Thanks :d

Sph's sgminer.
newbie
Activity: 21
Merit: 0
My P2pool should be OK now. Around 50Mh/s on it and estimated 3h to find a block.

You are all welcome on my powerful server Smiley

http://p2poolcoin.com:5567/static/

What algorithm?

Qubit, it's a qubit p2pool, the first !

I have some spike above 150Mh/s now. Join the pool, no need to register, just put your wallet address as username (-u wallet) and what you want in password (-p x).

I have no idea how to set up the qubit miner Sad could anyone post a little guide or refer me to somewhere where i could find one?
Thanks :d
sr. member
Activity: 349
Merit: 250
Stablehash owner here. I would like to formally apologize for the problems with the groestl pool. I am out of town right now and am doing everything I can to resolve the problems on my phone. Please PM me if you have any other problems.
Jump to: