This is the first post of 2020!
From Java programming, I am picking up Python.
[Side note: When I attended my final Java tutorial, I answered a question on GUI (graphical user interface, a screen “through which a user interacts with electronic devices such as computers, hand-held devices and other appliances. This interface uses icons, menus and other visual indicator (graphics) representations to display information and related user controls, unlike text-based interfaces, where data and commands are in text”, Techopedia, 2 Jan 2020).
What is so cool about this? I majored in History; I had taken Java to fulfil graduation requirements.
So my instructor’s comment changed my worldview, I mean – wow – I get coding (with much guidance from others).
So why not give new things a try? Especially if you’re learning to help others…]
Returning to the topic, I see the massive need for foundational knowledge. Thus, here is an attempt to make learning easier for many (including myself)…
ASCII is the acronym for the American Standard Code for Information Interchange. It is a code for representing 128 English characters as numbers, with each letter assigned a number from 0 to 127. For example, the ASCII code for uppercase M is 77. Most computers use ASCII codes to represent text, which makes it possible to transfer data from one computer to another.
Text files stored in ASCII format are sometimes called ASCII files. Text editors and word processors are usually capable of storing data in ASCII format, although ASCII format is not always the default storage format. Most data files, particularly if they contain numeric data, are not stored in ASCII format. Executable programs are never stored in ASCII format.
The standard ASCII character set uses just 7 bits for each character. There are several larger character sets that use 8 bits, which gives them 128 additional characters. The extra characters are used to represent non-English characters, graphics symbols, and mathematical symbols.
Several companies and organizations have proposed extensions for these 128 characters. The DOS operating system uses a superset of ASCII called extended ASCII or high ASCII. A more universal standard is the ISO Latin 1 set of characters, which is used by many operating systems, as well as Web browsers.
Another set of codes that is used on large IBM computers is EBCDIC.
Vangie Beal. (accessed 2 Jan 2020). ASCII. Webopedia.
…Technically, ASCII is 7-bit representing only 128 characters (0-127). The range 0-31 are control characters, with 32-127 representing alphabetical characters from A to Z, numerals from 0 to 9 and punctuation marks (though not in that order). ASCII only may be used to encode U.S. English.
Some people confuse codes above 128-255 to be ASCII, but technically speaking, they are not. As computers evolved, it became common to use an 8-bit byte. This last character allowed for an extra 128 characters, which is known as extended ASCII. Different systems implement extended ASCII differently, so there are compatibility issues that aren’t encountered in the first 128 characters.
American Standard for Information Interchange (ASCII). (accessed 2 Jan 2020). Techopedia.
A binary file is a file stored in binary format. A binary file is computer-readable but not human-readable. All executable programs are stored in binary files, as are most numeric data files. In contrast, text files are stored in a form (usually ASCII) that is human-readable.
Webopedia Staff. (accessed 2 Jan 2020). Binary file. Webopedia. [See also Binary (07 Oct 2019) by Computer Hope – https://www.computerhope.com/jargon/b/binary.htm].
… any of a number of mathematical systems, esp. one (Boolean algebra) devised using algebraic rules and symbols for the analysis of symbolic logic, which is now widely used in digital computers since its true-false results are compatible with binary numbers
Collins Dictionary (American English). (accessed 2 Jan 2020).
A Boolean system is based on things that can be either true or false, but not both. It links statements with words called operators, such as AND, OR, and NOT. Boolean systems are used to write computer programs, especially Internet search programs.
Longman Dictionary of Contemporary English. (accessed 2 Jan 2020).
… As of 2001, the US Department of Commerce’s National Institute for Standards and Technology (NIST) has adopted the Advanced Encryption Standard (AES) as the standard for government encryption (PDF). Since its adoption, AES has become a standard part of cryptography around the world, both in government and civilian applications.
AES is a form of symmetrical encryption and can be used to generate 128-bit keys, 192-bit keys, and 256-bit keys, depending on the number of encryption rounds data is subjected to. AES creates blocks of 16 bytes that are shifted, mixed, and substituted each round…
AES is incredibly secure, so much so that the US government considers AES128 sufficient to secure data classified as secret, and AES192 and AES256 safe for top secret data. AES is effectively unbreakable, and it’s easy to see why mathematically. A 128-bit encryption has 2 128 potential solutions, a 192 bit 2192, and a 256 has 2256 possible solutions. Do a quick calculation, and you’ll see why it would take even the most powerful computers an impossibly long time to crack it.
As for asymmetrical encryption, there’s currently no single standard in place. There is a long list of asymmetric encryption methods, but the most commonly used one by far is RSA. A variety of encryption systems make use of asymmetric encryption, such as DSA, Diffie-Hellman key exchange, ElGamal, YAK, and others…
There is a form of encryption considered unbreakable, when applied correctly, and it’s over 100 years old: The one-time pad.
One-time pads are a symmetric encryption that have very specific instructions to ensure their encryption is unbreakable. In order to be successful, a one-time pad has to:
- Be made up of completely random numbers;
- Have only two existing copies;
- Be used only once; and
- Be destroyed immediately after use.
One-time pads are impractical for use in the digital encryption world because of the difficulty that comes with a single-use encryption key: It’s hard to keep the key limited to exactly two copies, and destroying it after use is difficult if it’s stored digitally.
While they may not be used for digital encryption, one-time pads do demonstrate an important thing about encryption: Key security is paramount. A strong, computationally impractical to break key may as well be unbreakable unless it’s used improperly or stolen…
Brandon Vigliarolo. (19 Apr 2019). Encryption: A cheat sheet. https://www.techrepublic.com/article/encryption-a-cheat-sheet/.
*Why did the computer keep sneezing?
It had a virus.
*Why do Java developers wear glasses?
Because they don’t C# (see sharp).
* What do you call a computer that sings?
A Dell. (Like Adele the singer.)
[Selection : ) ] Computer Hope. (1 Dec 2019). https://www.computerhope.com/jargon/j/joke.htm.
Short for eXclusive OR, the XOR operator is a Boolean operation used in database searches and other searches that returns a TRUE value only if a document contains only one match.
computer XOR help
In the example above, the command would return results of documents or a value that contains either “computer” or “help”. However, it would not return the results if the documents or value contains both of these words.
XOR operator. (26 Apr 2017). Computer Hope.
Known as the exclusive OR operator, a Boolean operatorthat returns a value of TRUE only if just one of its operands is TRUE. In contrast, an inclusive OR operator returns a value of TRUE if either or both of its operands are TRUE.
XOR operator. (accessed 2 Jan 2020). Webopedia.
XOR algorithm of encryption and decryption converts the plain text in the format ASCII bytes and uses XOR procedure to convert it to a specified byte. It offers the following advantages to its users −
- Fast computation
- No difference marked in left and right side
- Easy to understand and analyze…
Cryptography with Python – XOR Process. (accessed 2 Jan 2020). Tutorials Point. https://www.tutorialspoint.com/cryptography_with_python/cryptography_with_python_xor_process.htm. [Consider also Adventures in Cryptography with Python – XOR Cipher. 25 Jul 2018. Abhishek Shukla. https://www.abhishekshukla.com/python/adventures-in-cryptography-with-python-xor-cipher/].
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