Project 6, 2015 Research Experience for Teachers Project 4, 2016

Secret Key, Public Key, Hash Algorithms, Protocols, Authentication, Integrity, Confidentiality, Availability

Relationship between ASCII, HEX, and binary

    Select a character from the ComboBox on the left and its ascii value (number), character value, hexadecimal value, and binary value are displayed, respectively. Select a number from the ComboBox on the right and see the same information displayed.

A bit is the smallest unit of information. Each bit can have either value 0 or value 1. A byte is the smallest addressable space in a computer. It consists of 8 bits. Therefore, a byte can represent any one of 256 distinct numbers.

Byte Representations:
    Number: a number from 0 to 255. But only the numbers 32 to 127 represent "printable characters."
    Character: a symbol from the following set, called printable:
abcdefghijklmnopqrstuvwxyz{|}~   plus space and delete.
    Binary: a collection of 8 bits with most significant bit on the left and least significant bit on the right. Represents a number between 0 and 255 as a radix 2 number. For example, the number 91 is expressed in binary as 01011011.
    Hexadecimal: since 8 bits is a little long, especially when stringing bytes together, hexadecimal is often used as shorthand for representing binary numbers. Each byte consists of two hexadecimal digits. That is, there are four bits per digit. Since 16 numbers can be represented by 4 bits the following are the hexadecimal digits, in increasing order: 0123456789ABCDEF. For example, the binary number 01011011 is expressed equivalently in hexadecimal as 5B.