Activity 1: Caesar Cipher
Encryption
- Go to Caesar Cipher Website
- Copy/paste Penn State Berks into Plaintext box.
- Encrypt the text using Key Size=3
Decryption
- Go to Caesar Cipher Website
- Copy/paste GOVMYWO DY ZOXX CDKDO LOBUC into the CIPHERTEXT box.
- Decrypt the ciphertext using Key Size= 10. What does it mean?
Activity 2: Bruce Force Attack to Caesar Cipher
Encryption
- Go to Crack Caesar Cipher Website
- Copy/paste Q IU AUIZB IVL PIZL EWZSQVO into the CIPHERTEXT box.
- Try to decrypt the message by try different keys. Be smart. You don’t have to try everything.
Activity 3: Code Breaking
Can you break the following secret message? It seems meaningless, but using a little math you can do it.
- Go to Frequency Analysis Page
- Copy/paste the following text into the text box and then click the frequency analysis button.
I kwuxcbmz qa i uikpqvm bpib uivqxctibma libi ikkwzlqvo bw i tqab wn qvabzckbqwva. Bpm nqzab lmdqkma bpib zmamujtm uwlmzv kwuxcbmza libm bw bpm uql-bemvbqmbp kmvbczg, itbpwcop bpm kwuxcbmz kwvkmxb ivl dizqwca uikpqvma aquqtiz bw kwuxcbmza mfqabml miztqmz. Miztg mtmkbzwvqk kwuxcbmza emzm bpm aqhm wn i tizom zwwu, kwvacuqvo ia uckp xwemz ia amdmzit pcvlzml uwlmzv xmzawvit kwuxcbmza. Uwlmzv kwuxcbmza izm jiaml wv bqvg qvbmozibml kqzkcqba ivl izm uqttqwva bw jqttqwva wn bquma uwzm kixijtm epqtm wkkcxgqvo i nzikbqwv wn bpm axikm. Bwlig, aquxtm kwuxcbmza uig jm uilm auitt mvwcop bw nqb qvbw i ezqabeibkp ivl jm xwemzml nzwu i eibkp jibbmzg. Xmzawvit kwuxcbmza, qv dizqwca nwzua, izm qkwva wn bpm Qvnwzuibqwv Iom ivl izm epib uwab xmwxtm bpqvs wn ia “i kwuxcbmz”; pwemdmz, bpm uwab kwuuwv nwzu wn kwuxcbmz qv cam bwlig qa bpm mujmllml kwuxcbmz. Mujmllml kwuxcbmza izm auitt, aquxtm lmdqkma bpib izm caml bw kwvbzwt wbpmz lmdqkma — nwz mfiuxtm, bpmg uig jm nwcvl qv uikpqvma zivoqvo nzwu nqopbmz iqzkzinb bw qvlcabzqit zwjwba, lqoqbit kiumzia, ivl kpqtlzmv’a bwga. Bpm ijqtqbg bw abwzm ivl mfmkcbm tqaba wn qvabzckbqwva kittml xzwoziua uisma kwuxcbmza mfbzmumtg dmzaibqtm ivl lqabqvocqapma bpmu nzwu kitkctibwza. Bpm Kpczkp–Bczqvo bpmaqa qa i uibpmuibqkit abibmumvb wn bpqa dmzaibqtqbg: ivg kwuxcbmz eqbp i kmzbiqv uqvqucu kixijqtqbg qa, qv xzqvkqxtm, kixijtm wn xmznwzuqvo bpm aium biasa bpib ivg wbpmz kwuxcbmz kiv xmznwzu. Bpmzmnwzm, kwuxcbmza eqbp kixijqtqbg ivl kwuxtmfqbg zivoqvo nzwu bpib wn i xmzawvit lqoqbit iaaqabivb bw i acxmzkwuxcbmz izm itt ijtm bw xmznwzu bpm aium kwuxcbibqwvit biasa oqdmv mvwcop bqum ivl abwziom kixikqbg.
Activity 4: The Vigenère Cipher
- Go to Vigenere Cipher Web Site
- Use Keyword TOP
- Encrypt Penn State Berks
- Compare the results to the Caesar Cipher
Activity 5: The Vigenère Cipher Decryption
- Go to Vigenere Cipher Web Site
- Use Keyword NEW
- Decrypt LYIZC WCTHRW