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Topic: IOTA - page 702. (Read 1473405 times)

rlh
hero member
Activity: 804
Merit: 1004
December 23, 2015, 09:26:13 AM
comments and questions redacted... I'll figure this out on my own. Tongue
legendary
Activity: 2142
Merit: 1010
Newbie
December 23, 2015, 09:17:56 AM
Unrelated question, regarding your tryte array (tryteTrits)  maybe I'm missing the pattern, but what determined the order of these sub-arrays (Each containing 3 trits)  If I were to create such an array, it would have looked like:

Code:
int[][] tryteTrits = 
    {
        {0,0,0}, {0,0,-1}, {0,0,1}
        {0,-1,0}, {0,-1,-1}, {0,-1,1}
        {0,1,0}, {0,1,-1}, {0,1,1}
         ...
    }

This seems to be a semi-natural progression of values.  Was there a good, logical reason for the much different ordering of trytes?

Your order gives the following numerical values:

 0   26    1
24  23  25
 3   2    4
legendary
Activity: 2142
Merit: 1010
Newbie
December 23, 2015, 09:15:11 AM
I've sent alpha version code to those who offered their help. The review shouldn't take much time, it was only back-end code. While we are waiting I'll start writing real (non-reference) version. The difference between these versions is that the latter will be more complex, but optimized.
rlh
hero member
Activity: 804
Merit: 1004
December 23, 2015, 09:09:08 AM
I had asked a couple questions regarding your comments... I'll dig into this deeper, later.  I'm starting to understand.

Unrelated question, regarding your tryte array (tryteTrits)  maybe I'm missing the pattern, but what determined the order of these sub-arrays (Each containing 3 trits)  If I were to create such an array, it would have looked like:

Code:
int[][] tryteTrits = 
    {
        {0,0,0}, {0,0,-1}, {0,0,1}
        {0,-1,0}, {0,-1,-1}, {0,-1,1}
        {0,1,0}, {0,1,-1}, {0,1,1}
         ...
    }

This seems to be a semi-natural progression of values.  Was there a good, logical reason for the much different ordering of trytes?
legendary
Activity: 2142
Merit: 1010
Newbie
December 23, 2015, 08:15:32 AM
FYI, I did a bit of counting.  Your address generator calls your transform() function 101(!) times on the state[] array.  This means that the seed is hashed 101 times.  When I count all of the lookups to F within the transform method, I see 19,683 lookups (which is your number.)  This means that F is accessed 1,987,983.

Also, I forgot to stop looking at benchmarks in the debugger (derp!).  My i5 is generating about 21 addresses/sec in Visual Studio while outside of VS I'm getting 108 addresses/sec.

Some hashings are not necessary to get an address, the logic (not reflected in the code) is:

1. Take random string of trits
2. Hash it to get a 243-trit account seed
3. By adding 0, 1, 2, ... to the seed and hashing it we get different key seeds
4. By hashing each key seed 9 times we get 27 key fragments (a hash contains 3 keys at once because a key fragment is 81 trits while a hash is 243 trits)
5. Each key fragment must be hashed 27 times, after each hashing only first 81 trits are taken
6. Once we get 27 key fragments hashed 27 times each we concatenate them into a 2187-trit string
7. Hashing of this string (requires 9 invocations of SaM transform function) gives 243 trits of the address

This method allows to deterministically generate infinite number of addresses not linked together (for an outside observer) by having a single account seed.
rlh
hero member
Activity: 804
Merit: 1004
December 23, 2015, 07:56:15 AM
Sorry for my ignorance but is "SaM" hashing the full process of taking a clear text string (the users passphrase) and converting it to an address hash?

Because in your code, you have operations such as 9 hashing rounds x (729 iterations for some left/right calculations + another 729 iterations for left/right index assignments and look ups.)  So, that operation alone is 13,122 operations within your transform method... which gets called multiple times per address.

Again, I need to dig into this and figure out the point of each step in your code, but with the exception of initializing the INDICES table just once, I have to execute all of your code for each address.

I hate to ask for a cheat, but are there other ways that some of this could be cached or simplified for barebones address creation?

SaM is just a hash function - https://github.com/JinnLabs/SaM/blob/master/src/SaM.java. A single hash requires 19683 lookups to F.

FYI, I did a bit of counting.  Your address generator calls your transform() function 101(!) times on the state[] array.  This means that the seed is hashed 101 times.  When I count all of the lookups to F within the transform method, I see 19,683 lookups (which is your number.)  This means that F is accessed 1,987,983.

Also, I forgot to stop looking at benchmarks in the debugger (derp!).  My i5 is generating about 21 addresses/sec in Visual Studio while outside of VS I'm getting 108 addresses/sec.

legendary
Activity: 2142
Merit: 1010
Newbie
December 23, 2015, 07:43:57 AM
bupqcn01srbheze1o999 -> 81 bits
bupqcn01srbheze1o -> 71 bits

=> mention it.

David will decide, my opinion is that too many details is rather bad than good. If someone managed to send bitcoins then their IQ is high enough to generate a good password.
legendary
Activity: 1181
Merit: 1002
December 23, 2015, 07:30:28 AM
Come on CfB you know what we mean:
"bupqcn01srbheze1o999" is randomized and fulfills your password suggestion before, but not after, disclosing the "trailing 9"-thing.
 Smiley

The security of this password is more than 80 bits, it's more than security of the password used by me LOL.

bupqcn01srbheze1o999 -> 81 bits
bupqcn01srbheze1o -> 71 bits

=> mention it.
legendary
Activity: 2142
Merit: 1010
Newbie
December 23, 2015, 07:21:59 AM
Come on CfB you know what we mean:
"bupqcn01srbheze1o999" is randomized and fulfills your password suggestion before, but not after, disclosing the "trailing 9"-thing.
 Smiley

The security of this password is more than 80 bits, it's more than security of the password used by me LOL.
legendary
Activity: 1181
Merit: 1002
December 23, 2015, 07:17:41 AM
So 'qwert999999999999999999' was thought to be more than 20 characters, but it is just 'qwert' 5 characters. I think the average people should know that.

It doesn't look as "randomized order".

Come on CfB you know what we mean:
"bupqcn01srbheze1o999" is randomized and fulfills your password suggestion before, but not after, disclosing the "trailing 9"-thing.
 Smiley
legendary
Activity: 2142
Merit: 1010
Newbie
December 23, 2015, 07:10:41 AM
So 'qwert999999999999999999' was thought to be more than 20 characters, but it is just 'qwert' 5 characters. I think the average people should know that.

It doesn't look as "randomized order".
hero member
Activity: 589
Merit: 500
December 23, 2015, 07:05:44 AM
Woww

What I just tested shows that the any additional '9' or '999999' in the end of the passphrase gives the same address as the original passphrase. But different addresses were returned if '9' or '9999' was inserted in the middle of the original passphrase.

That's correct behavior.

So 'qwert999999999999999999' was thought to be more than 20 characters, but it is just 'qwert' 5 characters. I think the average people should know that.

legendary
Activity: 1181
Merit: 1002
December 23, 2015, 06:56:58 AM
Woww

What I just tested shows that the any additional '9' or '999999' in the end of the passphrase gives the same address as the original passphrase. But different addresses were returned if '9' or '9999' was inserted in the middle of the original passphrase.

That's correct behavior.

I think this should be mentioned under step 3 of the "collection manual".
legendary
Activity: 2142
Merit: 1010
Newbie
December 23, 2015, 06:25:45 AM
Woww

What I just tested shows that the any additional '9' or '999999' in the end of the passphrase gives the same address as the original passphrase. But different addresses were returned if '9' or '9999' was inserted in the middle of the original passphrase.

That's correct behavior.
legendary
Activity: 1181
Merit: 1002
December 23, 2015, 06:12:50 AM
^
Seems so, ...., urrr, don't think I like that...
hero member
Activity: 589
Merit: 500
December 23, 2015, 05:55:56 AM
it's interesting! What is the algo again that derives adress from secrect phrase, and how does it give '9' such funny properties?

https://github.com/JinnLabs/SaM/blob/master/src/SaM.java:

Quote
Note that the hash of the empty string is all zeros, this can be used in cases when the hash of NULL should be NULL.

"9" is treated as "all zeros"/NULL.

Woww

What I just tested shows that the any additional '9' or '999999' in the end of the passphrase gives the same address as the original passphrase. But different addresses were returned if '9' or '9999' was inserted in the middle of the original passphrase.


legendary
Activity: 1540
Merit: 1000
December 23, 2015, 05:54:26 AM
Untill when do I have to collect my IOTA?


hero member
Activity: 695
Merit: 500
December 23, 2015, 05:48:35 AM
Untill when do I have to collect my IOTA?
legendary
Activity: 1666
Merit: 1020
expect(brain).toHaveBeenUsed()
December 23, 2015, 05:32:11 AM
it's interesting! What is the algo again that derives adress from secrect phrase, and how does it give '9' such funny properties?

https://github.com/JinnLabs/SaM/blob/master/src/SaM.java:

Quote
Note that the hash of the empty string is all zeros, this can be used in cases when the hash of NULL should be NULL.

"9" is treated as "all zeros"/NULL.

The java version of the algo seems to look more professional than the javascript one ;-)
legendary
Activity: 2142
Merit: 1010
Newbie
December 23, 2015, 05:13:33 AM
it's interesting! What is the algo again that derives adress from secrect phrase, and how does it give '9' such funny properties?

https://github.com/JinnLabs/SaM/blob/master/src/SaM.java:

Quote
Note that the hash of the empty string is all zeros, this can be used in cases when the hash of NULL should be NULL.

"9" is treated as "all zeros"/NULL.
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