REP 6.1

Bits are everywhere,and they can represent virtually anything. In fact, the previous sentence looks like 01000010 01101001 01110100 01110011 00100000 01100001 01110010 01100101 00100000 01100101 01110110 01100101 01110010 01111001 01110111 01101000 01100101 01110010 01100101 00101100 00100000 01100001 01101110 01100100 00100000 01110100 01101000 01100101 01111001 00100000 01100011 01100001 01101110 00100000 01110010 01100101 01110000 01110010 01100101 01110011 01100101 01101110 01110100 00100000 01110110 01101001 01110010 01110100 01110101 01100001 01101100 01101100 01111001 00100000 01100001 01101110 01111001 01110100 01101000 01101001 01101110 01100111 00101110 at the binary level. The bits themselves do not mean anything without a rule that tells us how to interpret them. This is the beauty of abstraction and a big part of the illusion that makes computers work the way they do.

Given a string of bits, such as 

01000100 01110101 01100100 01100101 00101100 00100000 01110100 01101000 01101001 01110011 00100000 01101001 01110011 00100000 01101111 01100010 01110110 01101001 01101111 01110101 01110011 01101100 01111001 00100000 01110100 01100101 01111000 01110100 00101110

the task of figuring out what they mean is impossible without establishing a method for decoding them. These bits may be a message encoded in ASCII, a save file for Peerless Fabio Twins, or part of an image. They could be any of these and more. Assuming that they are ASCII, mapping each set of 8 is trivial; just map them from one encoding to another.

Use the app below to read the message encoded in ASCII in the previous bitstring. Simply copy and paste the binary into the 'binary' pane and press the button.

The app shows different encodings of the same bits. It should be fairly obvious which is the intended encoding.

Your Task: A Digital Scavenger Hunt

Your task is to find and submit a secret message buried in binary. This task stresses that binary can encode different types of data depending on the rules for abstraction used to interpret it.

1. Click the download arrow below to obtain some bits. Before continuing to step number 2, look at the bits. What do you think is encoded? How different are the bits in different areas of the bitstring?

Download secret.txt The top-secret, for-your-eyes-only string of bits

1. Paste these bits (ALL OF THEM) into the binary pane of the app below (alternatively you can upload the file). Try the two types of conversions. Nothing obvious will be apparent, but remember how differently the bits were distributed in binary. You might find this tool to be useful to finish decoding the secret message.
   
   

Submit the following:

• The secret message.
• A brief outline of the process you used to find the message. Include dead ends!
• Answer the following short questions:
• Why is the sequence '11111111' repeated often in secret.txt? What does it represent?
• Which of the encodings (binary, decimal, hex, BASE64) is the most compact? Why?