1,608 reputation
1921
bio website
location Bangalore, India
age 32
visits member for 3 years
seen 3 hours ago

Security and Crypto Technologist


Feb
19
comment Which gives better deterministic encryption SIV or Plain ECB mode?
ok i meant message and block as same . let me edit the question
Feb
19
comment Which gives better deterministic encryption SIV or Plain ECB mode?
same holds good for ECB mode too .
Feb
19
accepted Security of Deterministic Encryption Scheme
Feb
19
asked Which gives better deterministic encryption SIV or Plain ECB mode?
Feb
13
comment Pseudo random permutation for arbitrary size domains
my last suggestion of , Feistel Networks + Cycle walking should help . please "PRP Luby Rack off revisited" by Naor and Reingold .
Feb
12
comment Pseudo random permutation for arbitrary size domains
@PaŭloEbermann using FPE with AES-NI is comparable speeds with AES-NI. Feistel networks with 10 or so rounds with AES-NI hardly slows it down .
Feb
12
answered Pseudo random permutation for arbitrary size domains
Feb
12
comment Should tweak be unique per message?
well that is not the point , the TBC can be used in any mode, it is just a block cipher with additional input tweak , for all practical purposes its block cipher and can be used in any mode .
Feb
11
answered Should tweak be unique per message?
Feb
11
comment Should tweak be unique per message?
Tweaks are designed to provide randomness to block ciphers directly rather than using the block cipher in some mode. I cannot agree for few things in the answer. 1. "Tweaks are never used directly", check out the different modes of FPE, tweaks are given directly by the user. 2."None of these needs to be visible to a programmer...", same check FPE. Now with this its appropriate to ask the comparison if its more secure to use a block cipher + IV per message or use a block cipher + same tweak for all messages !
Feb
11
comment Should tweak be unique per message?
if the developer does not need to know about tweak , how is the tweak generated/provisioned/provided as input to encryption algorithm , how is the same tweak provided again to decryption algorithm run in a different machine ?
Feb
11
revised Should tweak be unique per message?
more clarity
Feb
11
asked Should tweak be unique per message?
Feb
4
accepted Is 80 bits of key size considered safe against brute force attacks?
Feb
3
revised Is 80 bits of key size considered safe against brute force attacks?
edited question title
Feb
3
asked Is 80 bits of key size considered safe against brute force attacks?
Feb
1
comment Is knowing the distribution of input domain only way to do cipher text only attacks?
either way would be of help .
Jan
31
revised Is knowing the distribution of input domain only way to do cipher text only attacks?
more clarity
Jan
31
comment Is it ok to send part of digital signature if we have bandwidth constraints?
how would you verify ? if you have only part of signature ?
Jan
31
accepted Impact of distinguishing between random text and cipher text?