Editing Final Report 2011 (section)

===Technical Challenges===
The key technical challenges faced in the Cipher Analysis portion of the project are identified below.
# Cipher Possibilities
# Sample Size
# Code Ambiguities
# Circumstantial Unknowns

[[Image:The_Code.png|thumb|170px|right|Ambiguous letters.]]
The first challenge, cipher possibilities, refers to the almost infinite number of potential ciphers that could have been used; there are many different algorithms to transform plaintext to ciphertext. For example, considering just simple mono-alphabetic substitution ciphers, there are 26! (factorial) possible ciphers; that is over 400,000,000,000,000,000,000,000,000 or 400 trillion trillion ciphers<ref name=TheCodeBook>''The Code Book'', author Simon Singh, The Fourth Estate, 2000.</ref>.

The sample size of the source material, 44 letters, also adds challenges. Frequency Analysis was introduced in the Background section as being the traditional method of solving substitution ciphers, however it relies on an accurate representation of the letter frequency distributions. This typically requires a sample of at least 100 letters.

Code ambiguity refers to some of the letters in the Somerton code being hard to identify. For example, the first letter in the first and second line in the figure below could be M’s or W’s. Code ambiguities added further challenges to the cipher analysis.

Finally, the circumstantial unknowns of the case introduce more complications. It is not known what nationality the Somerton Man was so we cannot be sure what language any hidden message would be in.