[BCN] Uncovering CryptoNote technology and Bytecoin BCN FAQ

[Rias]

There has been an interesting topic on this board related to new-old cryptocurrency Bytecoin (BCN), which emerged recently but is apparently 1 year 8 months old. The name is confusing, since there is another Bytecoin (BTE), which is around 1 year old, but this is not where it gets interesting. Unlike BTE, BCN is not a Bitcoin fork (or rumored not to be such, didn't check the source code myself), but is rather based on some sort of "CryptoNote" technology.

Links:
Original BCN thread: https://bitcointalk.org/index.php?topic=512747.0
BCN website: https://bytecoin.org
CryptoNote website: https://cryptonote.org
CryptoNote forum: https://forum.cryptonote.org

This whole story is quite strange and is getting stranger and stranger with each new fact about this cryptonote and bytecoin-bcn. I've started this topic to summarize all information that we have today. I feel like the best solution is faq with proof-links.

FAQ

Technology

Q: What is CryptoNote technology?
A: "An open-source technology and concepts for the cryptocurrencies of the future" as stated on the website. Also, CN developers state it clearly that they are not a coin itself, but rather a technological concept that allows creation of new cryptocurrencies [1].

Q: How is CryptoNote related to Bitcoin?
A: CryptoNote allows anonymous payments through ring signature and one-time addresses [2]. Ring signature allows to sign the message/transaction on behalf of the group so that the network knows that the message was validly signed, but the identity of the signer is unknown. One-time addresses are created from one private key and help to hide the identity of the receiver, as only he can redeem the funds.

Q: How is Bytecoin BCN related to CryptoNote and Bitcoin?
A: Bytecoin is the first implementation of CryptoNote and also its reference code for further developments [1]. Bytecoin's code is claimed not to be a fork of Bitcoin's [3].

Q: Are there any forks of Bytecoin?
A: There is one fork started on April 18, 2014, called "Bitmonero". Official thread: https://bitcointalk.org/index.php?topic=563821.0

Community

Q: How is Bytecoin BCN related to Bytecoin BTE?
A: They're likely to not be linked at all. The only connection is the name. BTE is the 100% Bitcoin fork, while BCN is developed from scratch [4]

Q: Who developed CryptoNote?
A: This is where it gets unclear. Website and forum messages claim that there is a group of core developers, around 10 people with a "small community helping" them [5]. However, the names are likely to be fake as they can't be googled [6].

Q: Are CN and BCN developers the same people?
A: Cryptonote's developers repeatedly refer to Bytecoin's devs as "them" and also indicate that they used to collaborate closely on the earlier stages, but currently two teams don't have direct connections [5].

Q: When Bytecoin BCN blockchain started?
A: According to the block chain info, "the first block was founded 07/04/2012 05:00:00 (GMT)" [7].

Q: How big is Bytecoin BCN community?
A: Based on hash rate estimations, should be around 2000-3000 active miners [8]. Taking other altcoins into consideration, the community of users is generally much bigger than the number of active miners.

Q: How could this community stay unnoticed for more than 1.5 years?
A: It's unclear. The community has possibly had several meetups [3], and there are actual transactions in all the blocks randomly chosen [9]. However, the total secrecy behind them is amazing. There is also a BCN community in TOR-web with some strange encrypted message inside [13].

Q: Is it Cicada 3301?
A: We don't know for sure. The hidden message has had quotes related to some discussion of Cicada [14, 15]. There can also be messages somewhere else, like midi files [16].

Q: What are the puzzles?
A: The bytecoin community seems to post puzzles for the community, which seem to have rewards for those to be the first to solve [23, 24].

Q: Do they monitor the bitcointalk threads?
A: They do, but never say anthing. The official website has changed the background music to the one proposed by danteT on the bitcointalk.org thread [22].

Q: Is there a way to contact with the developers?
A: It seems like there is no direct contact with bytecoin developers, although they do post puzzles (see above). CryptoNote developers are rather active on their forum, having even posted the contribution opportunities for the community [25].

Usage

Q: How do I mine BCN?
A: Either through the native daemon [10], or through "minergate" pool [11].

Q: How much is reward for mining?
A: It follows a sophisticated formula, which retargets difficulty and reward each block [3]. First block reward was roughly 700k [17], current one should be under 130k [18].

Q: How often do blocks appear?
A: About 2 minutes [19].

Q: How BCN coins are emitted?
A: Some kind of Hash-based proof-of-work, called "CryptoNight" is used [3]. It is claimed to be CPU-only [2]. It is unlcear yet whether CryptoNight is actually ASIC-resistant, but it might possible be so [21].

Q: Is it worth mining BCN?
A: Seem like it is possible to mine the coin both solo and in pool even with the current difficulty [20].

Q: Is there a market for BCN trade?
A: There is nothing we're currently aware of except for OTC trade [12].

References:
[1] https://forum.cryptonote.org/viewtopic.php?f=5&t=11#p13
[2] https://cryptonote.org/inside.php
[3] https://bytecoin.org
[4] https://forum.cryptonote.org/viewtopic.php?f=5&t=11#p60
[5] https://forum.cryptonote.org/viewtopic.php?f=3&t=21#p73
[6] https://bitcointalk.org/index.php?topic=512747.msg6011193#msg6011193
[7] https://bitcointalk.org/index.php?topic=512747.msg5950616#msg5950616
[8] https://bitcointalk.org/index.php?topic=164569.msg5657766#msg5657766
[9] https://bitcointalk.org/index.php?topic=512747.msg6023372#msg6023372
[10] https://bitcointalk.org/index.php?topic=544715
[11] https://bitcointalk.org/index.php?topic=528848.
[12] https://bitcointalk.org/index.php?topic=531925
[13] https://bitcointalk.org/index.php?topic=512747.msg6035564#msg6035564
[14] https://bitcointalk.org/index.php?topic=512747.msg6089531#msg6089531
[15] https://bitcointalk.org/index.php?topic=512747.msg6090578#msg6090578
[16] https://bitcointalk.org/index.php?topic=512747.msg6093696#msg6093696
[17] https://bitcointalk.org/index.php?topic=512747.msg6032544#msg6032544
[18] https://bitcointalk.org/index.php?topic=512747.msg6035390#msg6035390
[19] https://bitcointalk.org/index.php?topic=512747.msg6089087#msg6089087
[20] https://bitcointalk.org/index.php?topic=528848.0
[21] https://bitcointalk.org/index.php?topic=557322.msg6266487#msg6266487
[22] https://bitcointalk.org/index.php?topic=512747.msg6145242#msg6145242
[23] https://bitcointalk.org/index.php?topic=512747.msg6178949#msg6178949
[24] https://bitcointalk.org/index.php?topic=512747.msg6267119#msg6267119
[25] https://forum.cryptonote.org/viewtopic.php?f=2&t=27#p115

[1715694124]

1715694124

[1715694124]

1715694124

[thankful_for_today]

There has been an interesting topic on this board related to new-old cryptocurrency Bytecoin (BCN), which emerged recently but is apparently 1 year 8 months old. The name is confusing, since there is another Bytecoin (BTE), which is around 1 year old, but this is not where it gets interesting. Unlike BTE, BCN is not a Bitcoin fork (or rumored not to be such, didn't check the source code myself), but is rather based on some sort of "CryptoNote" technology.

Great summary. Thank you Rias!

Does anybody understand CryptoNight hash?

[x0rcist]

Thanks for opening this topic!

[Rias]

I've added some questions on mining and Cicada connection theory. Also re-arranged the question a bit.

[Denni]

A coin has managed to be 80% mined in two years . . and nobody had a clue. A fantastic example of what CN can provide.

I think it's a perfect example of what deep web can provide. Next-gen crypto technologies remain undetected for 2 years. Who know what else deep web is hiding?

Even more, if what they say is true about it being anonymous, then the previous two years of usage is more than enough real-world data to provide to prove it. This is two more years than anything else.

If a full analysis were to be started now, and all transactions were truly anonymous amongst other things . . there would be absolutely no speculation based on two years of real data already existing.

Can you provide a meaning of this? Didn't understand it. You wanted to say that currently there are some doubts about the transactions? I mean you can check blocks yourself.

[Denni]

A coin has managed to be 80% mined in two years . . and nobody had a clue. A fantastic example of what CN can provide.

I think it's a perfect example of what deep web can provide. Next-gen crypto technologies remain undetected for 2 years. Who know what else deep web is hiding?

Even more, if what they say is true about it being anonymous, then the previous two years of usage is more than enough real-world data to provide to prove it. This is two more years than anything else.

If a full analysis were to be started now, and all transactions were truly anonymous amongst other things . . there would be absolutely no speculation based on two years of real data already existing.

Can you provide a meaning of this? Didn't understand it. You wanted to say that currently there are some doubts about the transactions? I mean you can check blocks yourself.

Yes, I have doubts. I don't currently have a way to test my doubts other than spending time reading the source code. I am hoping I am wrong, but it's still pretty new to me so I don't know how to test it so that I will feel comfortable with it.

It would great if everything I see is the truth, and I'm seriously hoping it's nothing but the truth . . but until I understand more, I'm staying cautious.

I'm waiting until I'm done reading and understanding the source code.

Are you a programmer? Maybe you will actually be able to bring a light to some of the questions here?

[EndlessWin]

Are you a programmer? Maybe you will actually be able to bring a light to some of the questions here?

that actually would've been really nice! ASIC-resistant part of the "CryptoNight" is what bothers me the most

[Johnny Mnemonic]

... ASIC-resistant part of the "CryptoNight" is what bothers me the most

What bothers you about it?

[EndlessWin]

... ASIC-resistant part of the "CryptoNight" is what bothers me the most

What bothers you about it?

it's existence afaik there is no proof that this technology is ASIC-resistant.

[Cheesus]

Yo folks! Where can I read more about the ring signature? Besides CryptoNote website.

I meant more technical details, you can find a lot of basic info on the CryptoNote.org but not the details.

Or I'm just blind

[smooth]

Yo folks! Where can I read more about the ring signature?

http://lmgtfy.com/?q=ring+signature&l=1

[Cheesus]

Yo folks! Where can I read more about the ring signature? Besides CryptoNote website.

I meant more technical details, you can find a lot of basic info on the CryptoNote.org but not the details.

Or I'm just blind

Have you tried the White paper and source code?

Source code is too hardcore for me... and I completely forgot about the Whitepaper. Going to look into it now.

Yo folks! Where can I read more about the ring signature?

http://lmgtfy.com/?q=ring+signature&l=1

*rolleyes emoticon from skype*

[Hazard]

Secret deep web cryptocurrency that has a formal .org webiste?

Color me suspicious.

[EndlessWin]

Secret deep web cryptocurrency that has a formal .org webiste?

Color me suspicious.

well it looks like they were trying to go public. who knows. maybe it's a leaky leak.

[Stanford]

Secret deep web cryptocurrency that has a formal .org webiste?

Color me suspicious.

In 2009 a lot of people who were suspicious to Bitcoin.

Everything which is revolutionary new to this world faced with people who don't trust innovations. Of course, you'd better to be keep your wits about everything in web world, but if you read more about bytecoin you'd have a deja vu. Somebody is telling Satoshi is one of the creators. I can't tell anything about Satoshi's involvement but  I know is that bytecoin is a HUGE step in crypto development.

[Bitcoin Fiction]

Secret deep web cryptocurrency that has a formal .org webiste?

Color me suspicious.

In 2009 a lot of people who were suspicious to Bitcoin.

Everything which is revolutionary new to this world faced with people who don't trust innovations. Of course, you'd better to be keep your wits about everything in web world, but if you read more about bytecoin you'd have a deja vu. Somebody is telling Satoshi is one of the creators. I can't tell anything about Satoshi's involvement but  I know is that bytecoin is a HUGE step in crypto development.

In 2009 almost nobody knew about Bitcoin. And who knew were suspicious because it was something that world have never seen.

Now when people acknowledged cryptos being suspicious about something that does not fit in the current "methodology of introducing new altcoin" is normal. It is to me at least.

I really dig Bytecoin and of course it's a huge step in cryptos but still, people have their right to be suspicious.  

[act now]

Maybe you should add to the FAQ info about the puzzles they are making. Or at least a history of puzzles like "music > hashes" etc.

[imready2rock]

yo ppl!

All this secrecy is giving me a headache seriously... All deepweb projects are so subtle ?

The only thing I heard about the deepweb (from my newbie-Bitcoin shore ) is Silkroad. And it wasn't secret and subtle like, at all.

[EndlessWin]

yo ppl!

All this secrecy is giving me a headache seriously... All deepweb projects are so subtle ?

The only thing I heard about the deepweb (from my newbie-Bitcoin shore ) is Silkroad. And it wasn't secret and subtle like, at all.

not a long time ago there was a thread on bitcointalk about the deepweb and it's wiki, you can try to find it.

you'll be amazed what you can find there

[tromp]

Yo folks! Where can I read more about the ring signature? Besides CryptoNote website.

I meant more technical details, you can find a lot of basic info on the CryptoNote.org but not the details.

Or I'm just blind

Have you tried the White paper and source code?

This is all that the whitepaper has on the CryproNight proof-of-work:

Code:

5.2
 The proposed algorithm
We propose a new memory-bound algorithm for the proof-of-work pricing function. It relies on
random access to a slow memory and emphasizes latency dependence. As opposed to scrypt every
new block (64 bytes in length) depends on all the previous blocks. As a result a hypothetical
“memory-saver” should increase his calculation speed exponentially.
Our algorithm requires about 2 Mb per instance for the following reasons:
1. It fits in the L3 cache (per core) of modern processors, which should become mainstream
in a few years;
2. A megabyte of internal memory is an almost unacceptable size for a modern ASIC pipeline;
3. GPUs may run hundreds of concurrent instances, but they are limited in other ways:
GDDR5 memory is slower than the CPU L3 cache and remarkable for its bandwidth, not
random access speed.
4. Significant expansion of the scratchpad would require an increase in iterations, which in
turn implies an overall time increase. “Heavy” calls in a trust-less p2p network may lead to
serious vulnerabilities, because nodes are obliged to check every new block’s proof-of-work.
If a node spends a considerable amount of time on each hash evaluation, it can be easily
DDoSed by a flood of fake objects with arbitrary work data (nonce values).

In item 4 they admit that this scheme, like scrypt-N, has a major drawback in being
rather slow to verify.

But in the preceding section, reproduced below, they point out a weakness in scrypt
that the new algorithm should have remedied:

Code:

Moreover, the scrypt construction itself allows a linear trade-off between memory size and
CPU speed due to the fact that every block in the scratchpad is derived only from the previous.
For example, you can store every second block and recalculate the others in a lazy way, i.e. only
when it becomes necessary. The pseudo-random indexes are assumed to be uniformly distributed,
hence the expected value of the additional blocks’ recalculations is 12 · N , where N is the number
of iterations. The overall computation time increases less than by half because there are also
time independent (constant time) operations such as preparing the scratchpad and hashing on
every iteration. 
...
This in turn implies that a machine with a CPU
2200 times faster than the modern chips can store only 320 bytes of the scratchpad.

If you really want details, you'll have to consult the code:

Code:

#define MEMORY         (1 << 21) /* 2 MiB */
#define ITER           (1 << 20)
#define AES_BLOCK_SIZE  16
#define AES_KEY_SIZE    32 /*16*/
#define INIT_SIZE_BLK   8
#define INIT_SIZE_BYTE (INIT_SIZE_BLK * AES_BLOCK_SIZE)

...

void cn_slow_hash(const void *data, size_t length, char *hash) {
  uint8_t long_state[MEMORY];
  union cn_slow_hash_state state;
  uint8_t text[INIT_SIZE_BYTE];
  uint8_t a[AES_BLOCK_SIZE];
  uint8_t b[AES_BLOCK_SIZE];
  uint8_t c[AES_BLOCK_SIZE];
  uint8_t d[AES_BLOCK_SIZE];
  size_t i, j;
  uint8_t aes_key[AES_KEY_SIZE];
  OAES_CTX* aes_ctx;

  hash_process(&state.hs, data, length);
  memcpy(text, state.init, INIT_SIZE_BYTE);
  memcpy(aes_key, state.hs.b, AES_KEY_SIZE);
  aes_ctx = oaes_alloc();
  for (i = 0; i < MEMORY / INIT_SIZE_BYTE; i++) {
    for (j = 0; j < INIT_SIZE_BLK; j++) {
      oaes_key_import_data(aes_ctx, aes_key, AES_KEY_SIZE);
      oaes_pseudo_encrypt_ecb(aes_ctx, &text[AES_BLOCK_SIZE * j]);
      /*memcpy(aes_key, &text[AES_BLOCK_SIZE * j], AES_KEY_SIZE);*/
      memcpy(aes_key, state.hs.b, AES_KEY_SIZE);
    }
    memcpy(&long_state[i * INIT_SIZE_BYTE], text, INIT_SIZE_BYTE);
  }

  for (i = 0; i < 16; i++) {
    a[i] = state.k[     i] ^ state.k[32 + i];
    b[i] = state.k[16 + i] ^ state.k[48 + i];
  }

  for (i = 0; i < ITER / 2; i++) {
    /* Dependency chain: address -> read value ------+
     * written value <-+ hard function (AES or MUL) <+
     * next address  <-+
     */
    /* Iteration 1 */
    j = e2i(a, MEMORY / AES_BLOCK_SIZE);
    copy_block(c, &long_state[j * AES_BLOCK_SIZE]);
    oaes_encryption_round(a, c);
    xor_blocks(b, c);
    swap_blocks(b, c);
    copy_block(&long_state[j * AES_BLOCK_SIZE], c);
    assert(j == e2i(a, MEMORY / AES_BLOCK_SIZE));
    swap_blocks(a, b);
    /* Iteration 2 */
    j = e2i(a, MEMORY / AES_BLOCK_SIZE);
    copy_block(c, &long_state[j * AES_BLOCK_SIZE]);
    mul(a, c, d);
    sum_half_blocks(b, d);
    swap_blocks(b, c);
    xor_blocks(b, c);
    copy_block(&long_state[j * AES_BLOCK_SIZE], c);
    assert(j == e2i(a, MEMORY / AES_BLOCK_SIZE));
    swap_blocks(a, b);
  }

  memcpy(text, state.init, INIT_SIZE_BYTE);
  for (i = 0; i < MEMORY / INIT_SIZE_BYTE; i++) {
    for (j = 0; j < INIT_SIZE_BLK; j++) {
      /*oaes_key_import_data(aes_ctx, &long_state[i * INIT_SIZE_BYTE + j * AES_BLOCK_SIZE], AES_KEY_SIZE);*/
      oaes_key_import_data(aes_ctx, &state.hs.b[32], AES_KEY_SIZE);
      xor_blocks(&text[j * AES_BLOCK_SIZE], &long_state[i * INIT_SIZE_BYTE + j * AES_BLOCK_SIZE]);
      oaes_pseudo_encrypt_ecb(aes_ctx, &text[j * AES_BLOCK_SIZE]);
    }
  }
  memcpy(state.init, text, INIT_SIZE_BYTE);
  hash_permutation(&state.hs);
  /*memcpy(hash, &state, 32);*/
  extra_hashes[state.hs.b[0] & 3](&state, 200, hash);
  oaes_free(&aes_ctx);
}