blazerx wrote:
creating 5 tables vs 4, will that increase cryptanalysis time? though i guess its hard to tell since cLength and Count are different.
You need to look at success rate to determine the optimal number of tables. I'm pretty sure that 5 tables is the optimal time-memory trade off for the success rate of that table set. I found the optimal time-memory trade off for a 99.9% success rate table set is 4 tables for both non-perfect and perfect table sets.
viewtopic.php?p=10969&f=2#p10969This table set is 99.9816%, if you use just 4 out of 5 of those tables it's 99.8974%. So I'm pretty sure 5 tables is the optimal time-memory trade off for 99.9816%.
** I'm guessing on this **
In general the least number of perfect tables to achieve a given success rate is the optimal time-memory trade off (for doing a look up). Also the number of non-perfect tables is the same as the perfect tables. Now if you want a success rate of 86.4646% then the optimal number of perfect tables is 1, but it will take forever to generate that table as your work factor will be the same as your chain length (a few thousand vs 13 [roughly the table work factor for most tables FRT has done in the past]). Also the shortest time to generate a table set for a given success rate is to have each chain be it's own table which will make it take forever to do a look up.
The "optimal time-memory trade off (for doing a look up)" does not account for false alarm checking because I don't know the formula for this and I have not taken the time to derive it. Ohh also this does not account for disk access which only matters if you search the table by seeking around in the file.