Developers Club geek daily blog

Overview of alternatives of Proof of Work. Part 2. Proof of Activity, Proof of Burn, Proof of Capacity and generals

3 years ago
We continue to transfer abrupt articles from the site here.

PoW vs PoS: what?


So, energy efficiency of Proof of Stake is two-edged sword. On the one hand, energy is not spent, with another – without these expenditure the model of the distributed consensus looks a little unstably.

What else arguments can be adduced? Against PoS the opinion that this scheme "does rich more richly" is expressed more than once. And really: who has more than all coins, will find more than all blocks and to get most profits, increasing number of these coins. Actually, in such look this charge can be stated and in the person PoW: the one who has invested more than all money in iron, will gain also bigger income, it is natural.

But the picture starts looking in a different way if we speak about cryptocurrency …

Read more »


Distributed network of base.network

3 years ago
base.network
"Freedom — is opportunity to tell that twice two – four. If this, all rest is permitted follows from here."
George Orwell — "1984"

In the modern world the different distributed technologies actively develop. Such projects as peer-to-peer payment Bitcoin system, the distributed microblogs (Twister), the distributed messengers successfully funktsioniruyet not the first year (for example, Tox). Business and has reached the full-fledged distributed sites.

Partially the functionality of the distributed sites is already implemented in such projects as Freenet and I2P. However similar projects have number of shortcomings. For example, now Freenet cannot be used for creation or distribution of dynamic content, such which uses databases or scripts. For access to similar networks it is often necessary to set the special software or to download databases of the huge sizes. Many P2P networks have big response time. Between the publication of information and subjects when it will be seen by other users passes a lot of time.

The offered base.network system is urged to eliminate similar defects of P2P networks and to integrate in itself all technical advantages of the centralized systems with freedom of exchange of information on the distributed networks.
It is some kind of attempt to create the protected decentralized network with small response time and properties of autonomy, fault tolerance and scalability. The key purpose of the project is ability to function even under pressure of the organizations exercising control, suppression of the publication, and also access restriction to information on the Internet. All aspects of the project are available in the form of open source code and are free. It allows to be convinced that the software does that is declared, and gives the chance to all developers to improve protection of network against attempts to limit freeware distribution of information.

Read more »


In state standard specification "Grasshopper" sat

3 years ago
In June of this year in Russia the new standard of block encryption — GOST P 34.12-2015 was accepted. This standard in addition to old kind GOST 28147-89 which is called "Magma" now and has the fixed set of substitutions, contains the description of the block cipher "Grasshopper". I will also tell about it in this post.

Read more »


Метод широкополосного сигнала (библиотека классов)

3 years ago

Предисловие


(из статьи КОМПЬЮТЕРНАЯ СТЕГАНОГРАФИЯ ВЧЕРА, СЕГОДНЯ, ЗАВТРА. Технологии информационной безопасности 21 века. /Барсуков В. С., к.т.н., Романцов А.П./1998/)
Задача надежной защиты информации от несанкционированного доступа является одной из древнейших и не решенных до настоящего времени проблем. Способы и методы скрытия секретных сообщений известны с давних времен, причем, данная сфера человеческой деятельности получила название стеганография. Это слово происходит от греческих слов steganos (секрет, тайна) и graphy (запись) и, таким образом, означает буквально “тайнопись”, хотя методы стеганографии появились, вероятно, раньше, чем появилась сама письменность (первоначально использовались условные знаки и обозначения).
В дальнейшем для защиты информации стали использоваться более эффективные на время создания методы кодирования и криптографии.
Как известно, цель криптографии состоит в блокировании несанкционированного доступа к информации путем шифрования содержания секретных сообщений. Стеганография имеет другую задачу, и ее цель — скрыть сам факт существования секретного сообщения. При этом, оба способа могут быть объединены и использованы для повышения эффективности защиты информации (например, для передачи криптографических ключей).
Как и любые инструменты, стеганографические методы требуют к себе внимания и осторожного обращения, так как могут быть использованы как для целей защиты, так и для целей нападения.

Алгоритм


В соответствии с методом широкополосного сигнала, каждый бит данных кодируется последовательностью изменённых яркостей пикселей в соответствии со значениями бит псевдослучайной последовательности.
Метод широкополосного сигнала предполагает возможность выработки у отправляемой и принимающих сторон одинаковой псевдослучайной последовательности или, по крайней мере, псевдослучайных последовательностей со статистическими характеристиками эквивалентными равным.
При этом в качестве контейнера для размещения данных может выступать не только само изображение, но и обратимое преобразование этого изображения, например, спектр, получаемый в результате Фурье преобразований. Наличие большого числа библиотек, реализующих Фурье преобразований (во всевозможных вариантах быстрых версий), делает реализацию алгоритмов не очень сложной задачей для программирования.

Read more »


Минимализм в криптографии, или схема Even–Mansour

3 years ago
image


Израильские ученые Шимон Ивэн (Shimon Even) и Ишай Мансур (Yishay Mansour) еще в 1997 году задались вопросом: насколько минимальной конструкцией может обладать стойкий блочный шифр? Под минимальностью они подразумевали число конструктивных элементов в схеме шифра, а под стойкостью — любую (формально верную) оценку снизу сложностей атак на этот шифр. Как говорится, под катом — описание минимального (и по сей день) блочного шифра с доказуемой стойкостью.

Read more »


NW.js (Node-Webkit) + Rutoken = (Has begun) RutokenJS

3 years ago
Has decided to create the module (C/C ++ Addons) for NW.js for work with Rutokenami and to share code with community, and also to invite you to participate in this Open source the project.

The idea essence in that it was possible to use all opportunities of Rutoken in NW application by means of pure and clear JavaScript, and also this module can be used in Node.JS or io.js.

API RutokenJS
  • CKR initialize ()
  • bool isInitialize ()
  • CKR finalize ()
  • object countSlot ()
  • object getLibInfo ()
  • object getSlotInfo (int slot)
  • object getTokenInfo (int slot)
  • object getMechanismList (int slot)
  • object getObjectList ()
  • CKR login (int slot, string pin)
  • CKR loguot ()
  • object random (int size)
  • CKR initToken (int slot)
  • CKR openSession ()
  • CKR closeSession ()
  • CKR closeAllSessions ()
  • object getSessionInfo ()
  • CKR getOperationState ()
  • CKR setOperationState ()


Read more »


Overview of alternatives of Proof of Work. Part 1. Proof of Stake

3 years ago
We continue to transfer abrupt articles from the site Bytecoin.org. Today — "Alternatives for Proof of Work, Part 1: Proof Of Stake" Ray Patterson (Ray Patterson).
Also read transfer to "Short history of evolution of proof-of-work in cryptocurrencies": part 1 and part 2.


Criticism of Proof of Work


As all of us remember, Proof of Work was born in far 1993 in family of cryptographers; parents designated it career of the defender from DoS and spam. However in 2008 to it the tempting sentence from certain anonymous author with yaposky accent has arrived: to become basis for the distributed server of time stamps. The scheme was represented idle time: nodes of network "vote" for the version of history of transactions, putting the capacities in calculation of "rare" hashes. The version which has received majority of votes is accepted by other nodes as the reference.

Ensuring big total power of network was important point: for protection against the potential malefactor with its potential 51% of resources. However the initial concept of PoW meant small tasks which the client has to execute to get access to server resources. Within such model of protection against DoS even small capacities of the client will not prevent respectable use of resource, and big simply were not required. Therefore the motivation for work of mayner has been implemented simply: "in kind", bitcoins, i.e. actually money.

And everything has changed it.

Read more »


In Telegram spammers appeared?

3 years ago
Probably that day when and in the popular Telegram messenger spammers appeared came though it and should have been expected. This morning received 12 messages of such plan:

image

Upon transition the link redirektit on url:
ody://tapgerine_ios_campaign

Apparently, the link for owners of iPhone and, perhaps, there something bad. Most it is not possible to check because at me costs Telegrams on poppy.
There is open a question how even if in a minute to write 12 messages with such volume of the text?

UPD:
How to be protected from spammers? I did not find the section where it is possible to set the filter of receipt of messages only from the contact list in settings.

Read more »


Mobile phones for/against intelligence services

3 years ago
— Hello, it you from FSB are called.
— I know.
— From where?
— You to me on the switched-off mobile phone have phoned.


What most protected phone?

Here what phones became the last 2 weeks inhabitants of my backpack. Aware people will understand at once that it for two tubes at the left.

The more I dug, the became more sad to me. Everyone (the second?) the person on Earth carries with himself bug and for just like that gives all the communication on a silver platter to the third parties. And anybody about it does not take a steam bath except professional paranoids.

Thus that it is more than phones on the planet, than all other devices together taken (has a little bent, but almost so), catastrophically it is not enough materials. For example, I still plainly have not found descriptions of those teams of the operator which it is reserved turn on phone on the wiretap. Or how operators and bodies fight (and whether fight) against scramblers?

Why is not present hacker / opensorsnykh projects of phones?, the notebook was notched, than the mobile phone is more difficult?
(Though there are which-what discussions).

Give for second we will reflect, hacker phone as if looked?
What functions it would have, than it would be stuffed from iron and from software.
For now we look that is in the market, what piece solutions are already implemented that it is possible to spot at them.

Read more »


Cryptography on Python: enciphering of information and creation of electronic digital signatures by means of PyCrypto packet

3 years ago


Long suffered with PyCrypto, this article and full implementation of the following protocol as a result has turned out:

Sending stage:

1. Alice signs the message with the digital signature and ciphers its public key of Bob (asymmetric algorithm).
2. Alice generates random session key and ciphers this key the message (by means of the symmetric algorithm).
3. The session key is ciphered by public key of Bob (asymmetric algorithm).
Alice sends to Bob the ciphered message, the signature and the ciphered session key.

Reception stage:

Bob receives the ciphered Alice's message, the signature and the ciphered session key.
4. The bean decrypts session key the private key.
5. By means of the session key received, thus, Bob decrypts the ciphered Alice's message.
6. The bean decrypts and checks Alice's signature.

Read more »