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seen May 24 at 12:11

Feb
17
awarded  Scholar
Feb
17
accepted Low complexity implementation of a small blocksize cipher (< 64 bit)
Feb
16
comment Low complexity implementation of a small blocksize cipher (< 64 bit)
@D.W. I had concluded that a block cipher would be better than a stream cipher because of its avalanche properties. AFAIK, with a stream cipher, bit 13 (for example) could only influence bits 13 to 44.
Feb
16
comment Low complexity implementation of a small blocksize cipher (< 64 bit)
Thanks for the responses. The application transmits a standalone 44-bit message (incl seq no and status bits) approximately every hour. Effectively in ECB mode. The cipher will be a software implementation a 16-bit microprocessor. The main constraint is limited memory. Speed is not a major issue. There will be at most 7 different keys ever used, all generated by me. Based on the transmit frequency, the device will generate less than 2^17 blocks over its lifetime.
Feb
16
comment Low complexity implementation of a small blocksize cipher (< 64 bit)
@D.W. thanks, my eyes were lighting up reading about RC5...very simple, should be easy to do a 44-bit version, but.... patented until 2015.
Feb
16
comment Low complexity implementation of a small blocksize cipher (< 64 bit)
@curious Thanks for the tip on PRESENT, i can think of several applications where that would be useful. Unfortunately here am constrained to 44-bits.
Feb
15
awarded  Student
Feb
15
asked Low complexity implementation of a small blocksize cipher (< 64 bit)