Seecrets on Security: A gentle introduction to cryptography

Written by Stan Seecrets

Withrepparttar increasing incidence of identity thefts, credit card frauds, social engineering attacks,repparttar 136799 digital world is facing challenges inrepparttar 136800 years ahead. Obviously, cryptography, a young science, will play a prominent role inrepparttar 136801 security of protecting digital assets. This article tries to explainrepparttar 136802 basics of cryptography (encryption) using plain language.

Let us takerepparttar 136803 example of scrambling an egg. First, crackrepparttar 136804 shell, pourrepparttar 136805 contents into a bowl and beatrepparttar 136806 contents vigorously until you achievedrepparttar 136807 needed result - well, a scrambled egg. This action of mixingrepparttar 136808 molecules ofrepparttar 136809 egg is encryption. Sincerepparttar 136810 molecules are mixed-up, we sayrepparttar 136811 egg has achieved a higher state of entropy (state of randomness). To returnrepparttar 136812 scrambled egg to its original form (including uncrackingrepparttar 136813 shell) is decryption. Impossible?

However, if we substituterepparttar 136814 word “egg” and replace it with “number”, “molecules” with “digits”, it is POSSIBLE. This, my friend, isrepparttar 136815 exciting world of cryptography (crypto for short). It is a new field dominated by talented mathematicians who uses vocabulary like "non-linear polynomial relations", "overdefined systems of multivariate polynomial equations", "Galois fields", and so forth. These cryptographers uses language that mere mortals like us cannot pretend to understand.

Inrepparttar 136816 computer, everything stored are numbers. Your MP3 file is a number. Your text message is a number. Your address book is a longer number. The number 65 representsrepparttar 136817 character "A", 97 forrepparttar 136818 small "a", and so on.

For humans, we recognize numbers withrepparttar 136819 digits from 0 to 9, where else,repparttar 136820 computer can only recognize 0 or 1. This isrepparttar 136821 binary system which uses bits instead of digits. To convert bits to digits, just simply multiplyrepparttar 136822 number of bits by 0.3 to get a good estimation. For example, if you have 256-bits of Indonesian Rupiah (one ofrepparttar 136823 lowest currency denomination inrepparttar 136824 world), Bill Gates’ wealth in comparison would be microscopic.

The hexadecimal (base 16) system usesrepparttar 136825 ten digits from 0 to 9, plusrepparttar 136826 six extra symbols from A to F. This set has sixteen different “digits”, hencerepparttar 136827 hexadecimal name. This notation is useful for computer workers to peek intorepparttar 136828 "real contents" stored byrepparttar 136829 computer. Alternatively, treat these different number systems as currencies, be it Euro, Swiss Franc, British Pound andrepparttar 136830 like. Just like an object can be priced with different values using these currencies, a number can also be "priced" in these different number systems as well.

To digress a bit, have you ever wondered why you had to study prime numbers in school? I am sure most mathematics teachers do not know this answer. Answer: A subbranch called public-key cryptography which uses prime numbers especially for encrypting e-mails. Over there, they are talking of even bigger numbers like 2048, 4096, 8192 bits.)

When we want to encrypt something, we need to use a cipher. A cipher is just an algorithm similar to a recipe for baking a cake. It has precise, unambiguous steps. To carry outrepparttar 136831 encryption process, you need a key (some called it passphrase). A good practice in cryptography needsrepparttar 136832 key used by a cipher must be of high entropy to be effective.

Data Encryption Standard (DES), introduced as a standard inrepparttar 136833 late 1970's, wasrepparttar 136834 most commonly used cipher inrepparttar 136835 1980's and early 1990's. It uses a 56-bit key. It was broken inrepparttar 136836 late 1990’s with specialized computers costing about US$250,000 in 56 hours. With today's (2005) hardware, it is possible to crack within a day.

Subsequently, Triple-DES superseded DES asrepparttar 136837 logical way to preserve compatibility with earlier investments by big corporations (mainly banks). It uses two 56-bit key using three steps:-

1. Encrypt with Key 1. 2. Decrypt with Key 2. 3. Encrypt with Key 1.

The effective key length used is only 112-bits (equivalent to 34 digits). The key is any number between 0 and 5192296858534827628530496329220095. Some modifyrepparttar 136838 last process using Key 3, making it more effective at 168-bit keys.

Why Mad Cap's Is Madonna's Favorite Puzzle

Written by David D. Deprice


Fromrepparttar warped minds that brought you Chainz comes Mad Caps, a puzzle game gone MAD!

Send bottle caps flying with every move to get your fill of tasty soda. Zap caps with rayguns, target'em with rockets or letrepparttar 136479 alien transform them. Collect letters to spell Mystery Words along with other "under-the-cap" bonuses.

Let Mad Caps quench your thirst for fun!

Full Version Features:

* Unlimited Play * 3 Exciting Play Modes * 7 Crazy Bonus Caps * Valuable "Under-The-Cap" Bonuses * Dizzying Array of Kooky Bottle Caps * Fantastic Music Soundtrack and Nutty Sound Effects

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