Computers use a variety of numbering and character encoding formats for processing efficiency (not for confidentiality). For cyber competitions, student must be able to convert a computer number format or text (ASCII) encoding format to the other equivalent numeric or text formats. Use a conversion tool (see links below).

Binary, octal, decimal and hexidecimal are popular positional numeric systems that can be used for arithmetic operations. Base64 is a binary-to-text encoding scheme that translate data into an ASCII string format using a radix-64 representation. ASCII is a character encoding standard for electronic communication that assigns a numeric value to 256 text and special characters. Unicode is a expansion to ASCII with support for over 1.4m characters.

Numbering and Encoding Systems:

Below are the most popular numbering and character encoding schemes use : 

    • Binary – Base2 (characters = 0,1)  :  core base for computer processing 
    • Octal – Base 8 (characters = 0,1,2,3,4,5,6,7)
    • Decimal – Base 10 (characters = 0,1,2,3,4,5,6,7,8,9)
    • Hexidecimal – Base 16 (characters = 0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F)
    • ASCII  – Text characters that have a corresponding numeric value
    • Unicode – International standards based on a superset of ASCII plus characters from all written languages. 
    • Base32 – binary-to-text encoding that produces an ASCII string format by translating the data using 32 characters  (UPPER CASE ALPHA + numeric) . Either three Alpha (XYZ) or three numeric (0,1, 3) are not used based on the variation.  
    • Base64binary-to-text encoding that produces an ASCII string format by translating the data using 64 character representation (upper and lower case alpha, numeric, ‘+’, and ‘/’ symbols….  with the ‘=’  as no value padding)
    • Other – A variety of additional bases may used depending upon the circumstances

Conversion Tools:

References: