[A51] Bit position , table structure and gpu in A51 tables

[fritchkornia at keemail.me]

Hi

I have a few questions regarding the A5/1 tables. I tought after a quick 
reading that the plaintext equivalent  of the tables was the LFSRs state 
after 122 clocking and the output the 64 first bit of keystream (after 64 
further clocking) with a simple reduction function  output = new plaintext

However while testing there is a Bit position that poped up . Does it mean 
that the compute function differ for each steps or is it just different in 
each tables ?

IS there a simple guide to understand the table structure somehow .

Finally what is the purpose of the GPU when finding new KC ? Is it just for 
the compute/reduction step ?


Best Regards

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.srlabs.de/pipermail/a51/attachments/20160318/937f77a9/attachment.html>