Math 348:02 - Spring 2020

ZEPAS ZNXEV GJNWL KSFRR PYFBZ XDXJR ECXXU VAREG UNGVQ MUREW PHWYY YOMFN GIPAW FCSEG HPBRO BRREX DXTBY PKPWA TMPXA FGLAY WEFXI THUZE FHFQR AEMHU RPLXR JVRPA SERZK EIGVS JTFLJ ENPWG ULELG HEZAR WATXD XTVEW PIFBS IOLCE NXNNH TRVOP OFNQW MVRZE PBQVN RWWFN VRWGR UVWOT ZNECS TGRAH KPSQJ MPAOL RENEC GGINR HURQK LHSNQ KNGZN XDXAN GMYBO ARZAK OFFSY BOGRH SBHUE YPZSE FAWLO AHRZX FTEEZ NOGRK AHFTR LEEZ

1. Use a Kasiski attack to decide what the possible key lengths might be.
2. Use your key length and a frequency attack on the individual slices of the message to decipher it.

Since it is tedious to manually count letter frequencies, trigrams and distances, one might wish to write software to do it or use publicly available software. For example, software at this cryptography website will perform such counts and calculations automatically.