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seen Jul 2 at 0:55

May
21
comment How were the number of rounds for different key sizes of AES selected?
$N_r = len(key)/4 + 6$.
Apr
22
comment How to perform file encryption using 128-Bit AES?
let us continue this discussion in chat
Apr
22
comment How to perform file encryption using 128-Bit AES?
@John Paul Parreño Such questions are better suited for Stack Overflow. Word of advice, if you are new to cryptography and wish to implement a cipher yourself, I'd suggest trying something simpler than AES at first, such as RC6.
Apr
22
comment Does the Biclique attack on AES pose a credible risk to its security?
At the moment, no cryptanalytic attack on full AES is computationally feasible. Hence, there is no practical threat. en.wikipedia.org/wiki/Advanced_Encryption_Standard#Security
Apr
22
comment ID-Secret Scheme
True. This was the first crypto-protocol I attempted to design and there are of course obvious flaws and design oversights. As for the problem faced, asymmetric cryptography proved to be an excellent solution.
Feb
23
comment How can one share information using the 'host-proof' paradigm?
@Travis In Adobe Air you can sign your applications with a certificate issued by a recognized certification authority. The problem with cryptography in AS3 is that it is slow. Thankfully there is a way to circumvent this limitation: using Air Native Extensions, but this requires you to publish your applications as native installers which cannot be signed. If speed is not a requirement, this may be a viable solution on first thought.
Feb
22
comment Which one of the Block Cipher modes is the best?
@PaĆ­lo Ebermann The SSL vulnerability you describe is present in TLS 1.0 and lower, not only in SSL 3.0.
Feb
22
comment Combating traffic analysis over request-response protocols
I have updated the question to include more information on what I am trying to hide.
Jan
12
comment Two mutually untrusted parties want to exchange data: how to ensure each one gets the data it needs?
@Alexandre H. Tremblay Can the trusted third party provide additional data given that it does not exceed 1KB?
Nov
20
comment Derived Shared Key vs Distinct Keys?
I'm aware of hybrid encryption. In what I am describing, asymmetric encryption is used to deliver 2 symmetric keys to both parties. These 2 symmetric keys are then XORed to produce an effective key that is then used for bulk encryption. I'm wondering why this is done instead of using both keys in the way I described in the question...
Oct
13
comment Key Length & Hashing
Why not just use a PRNG?
Oct
11
comment Encrypt-then-MAC Confidentiality, Integrity and Authenticity
I don't see why not...
Oct
10
comment Encrypt-then-MAC Confidentiality, Integrity and Authenticity
@John: Maybe you meant HMAC instead of HASH?
Sep
27
comment How can I prevent a message replay with RSA?
How will including a signed random value solve the problem? How does the recipient know that the nonce hasn't been repeated without storing every previous nonce?
Sep
27
comment How can I prevent a message replay with RSA?
For my purposes, the expiration time is time+5 seconds. That gives an attacker a 5 second window to attack. For my system, a single replay can be destructive.
Aug
23
comment Why does nobody use (or break) the Camellia Cipher?
Yes, Yahoo! uses Camellia as the bulk cipher when TLS is used. What is more interesting is that they use a 1024-bit certificate...
Aug
21
comment Is public-key cryptography the only option in this scenario?
Thanks but SPEKE doesn't require the password in cleartext on the server-side, the password can be stored in cleartext, as hash(password) or as hash(password)^2...
Aug
20
comment Is public-key cryptography the only option in this scenario?
Which PAKE method would you suggest, SRP or SPEKE and why?
Aug
18
comment Is public-key cryptography the only option in this scenario?
I have edit the question to clear any confusion, I apologize for the unclarity.
Aug
18
comment Is public-key cryptography the only option in this scenario?
I have edit the question to clear any confusion, I apologize for the unclarity.