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bio website bradconte.com
location Texas, USA
age 27
visits member for 3 years, 1 month
seen 1 hour ago

I'm a software engineer with a background in computer science and mathematics. I love cryptography, math, and Linux.

More about me on my website: http://bradconte.com/about.


Sep
23
revised Why is triple-DES using three different keys vulnerable to a meet-in-the-middle-attack?
edited tags
Sep
23
revised Meet-in-the-middle with checking complexity
Added new tag.
Sep
21
comment Can I construct a feasible stream cipher out of HMAC and a secure hash algorithm?
Very typically, IVs are prepended to the ciphertext and MAC's are appended to it.
Sep
21
comment Can I construct a feasible stream cipher out of HMAC and a secure hash algorithm?
@MaxthonChan: Yes, you can keep the IV with the ciphertext.
Sep
19
comment Can I construct a feasible stream cipher out of HMAC and a secure hash algorithm?
Yes, they should be independent, assuming you want to use the key more than one time.
Sep
18
answered Which encryption method supports random reads?
Sep
18
revised Can I construct a feasible stream cipher out of HMAC and a secure hash algorithm?
Corrected the alternate proposal's relation to CFB mode.
Sep
18
comment Can I construct a feasible stream cipher out of HMAC and a secure hash algorithm?
Whoops, you are right. Not sure how I missed that, considering what I used it for CFB mode.
Sep
18
answered Can I construct a feasible stream cipher out of HMAC and a secure hash algorithm?
Sep
18
comment Encrypting 8 times with 8-bit key beneficial?
For ciphertext only, aside from algorithm-specific properties/weaknesses, I don't know of anything better than brute-force.
Sep
18
reviewed Approve suggested edit on modular-arithmetic tag wiki excerpt
Sep
18
revised Encrypting 8 times with 8-bit key beneficial?
Reworded for clairty.
Sep
18
reviewed Reject suggested edit on modular-arithmetic tag wiki
Sep
18
reviewed Reject suggested edit on linear-cryptanalysis tag wiki
Sep
18
reviewed Reject suggested edit on linear-cryptanalysis tag wiki excerpt
Sep
18
revised Encrypting 8 times with 8-bit key beneficial?
Latex formatting, added relevant tags.
Sep
18
answered Encrypting 8 times with 8-bit key beneficial?
Sep
18
comment Estimating bits of entropy
Do we have anything better than that for practical entropy estimates in real life? We don't (well, rarely) deal with truly random events, just events where we have a distribution and very little additional insight beyond that distribution. (Top of my head examples: hard drive seek times, mouse coordinates, etc. They aren't truly random, but at some level of detail you're stuck with a distribution of behavior and no way to analyze the source any more finely.)
Sep
18
comment Estimating bits of entropy
I would think we could pragmatically estimate entropy via a combination of statistics and good analysis. Empirically measure a statistical distribution on the lowest level of the entropy source that you can. Calculate $H$ where $Pr[x_i]$ is calculated from that distribution. How good an estimate of entropy this produces will rely on how good of a choice was made for "lowest level". Eg, if you chose the output of a PRG seeded by 0 you will have a false high entropy due to a poor decision. But if you choose a level the attacker won't have deeper insight to, the estimate should be good.
Sep
15
comment Inverting the encryption equation of a symmetric cipher
Not to dissuade you from asking cryptography questions here, but that course has a discussion forum with participants and TAs who should be familiar with the current state of the course and the recently covered material, which will give them good insight into answering questions like this.