Questions tagged [entropy]
In computing, entropy is the randomness collected by an operating system or application for use in cryptography or other uses that require random data. This randomness is often collected from hardware sources, either pre-existing ones such as mouse movements or specially provided randomness generators.
13
questions with no upvoted or accepted answers
11
votes
1
answer
1k
views
Entropy sources used by modern Windows
A comment on a Microsoft blog from 2005 mentions over 150 sources of entropy for the Windows CryptGenRandom function. The majority of sources come from low-level system information (precise stat ...
- 66.7k
3
votes
2
answers
288
views
Quantify security strength from entropy and lifetime
Entropy or randomness is a quantitative measure of security strength for various types of passcodes, but in current times with digital technology, breaches, and cracking tools it seems that lifetime ...
- 41
3
votes
1
answer
411
views
using HW random number generator as source of entropy
Currently I am using haveged on my server as source of entropy.
My Server is used as KVM hypervisor, to run virtual machines.
I did not use haveged at the beginning, and I noticed the VMs were ...
- 1,721
2
votes
0
answers
89
views
Why does Bluetooth Low Energy Secure Connections with Passkey Entry check the Passkey bit by bit?
If we want to enable an authenticated connection via BLE the passkey method seems like a good idea. A 6-digit PIN is generated randomly on one device and has to be entered on the other - these 20 Bit ...
- 71
2
votes
0
answers
294
views
How much entropy does Apple Touch ID sensor read fingerprint has?
Iphone uses by default 6-digit PIN that has an entropy of 19.93 bits
When iPhone processes the fingerprint, how much entropy does it have?
How long should standard passphrase be until it is as ...
- 31
2
votes
0
answers
313
views
Passphrase generator and strength & recovery time estimator. Right strength and randomness?
Questions about the strength of pass phrases frequently popup, as does: how to generate a strong passphrase? I tried to combine both in a tool. The free tool also includes recovery time estimations ...
- 525
1
vote
0
answers
124
views
Comparing HAVEGE and Jitter Entropy algorithms
How does the HAVEGE method (or rather, the specific adaption of it as used in haveged) for generating randomness from timing differ from that of the Jitter Entropy method? Is there any research ...
- 66.7k
1
vote
0
answers
455
views
Digest algorithm for the PRNG in OpenVPN
Considering the following OpenVPN (2.4) option from the manual:
--prng alg [nsl]
(Advanced) For PRNG (Pseudo-random number generator), use digest algorithm alg (default=sha1), and set nsl (default=16)...
- 265
1
vote
0
answers
280
views
Entropy in Address Randomization
I am trying to understand the concept behind address randomization (ASLR). I'm reading the related wikipedia article which states:
Security is increased by increasing the search space. Thus,
...
- 1,095
0
votes
0
answers
166
views
How does user activity affect entropy generation process in GnuPG?
Earlier today, I was using gpg to generate keys for work. While doing so, I noticed:
We need to generate a lot of random bytes. It is a good idea to
perform some other action (type on the keyboard, ...
0
votes
0
answers
190
views
How much entropy is needed for encrypting data locally?
I understand that, when storing data on the cloud or something else that might get leaked to the public, the security margin should be at least 128 bit, 256 bit should be used for data that should ...
- 727
0
votes
0
answers
253
views
Generating a secret token: security concerns other than min-entropy?
I'm trying to compare two techniques for generating an OAuth 2 PKCE code_verifier.
For each character, get a random byte and "mod 66" to map to one of the 66 valid characters.
For each ...
- 172
0
votes
1
answer
240
views
Are weak entropy sources worth it?
I maintain an operating system that can be deployed to embedded devices with highly diverse capabilities. One of the aspects of porting the OS to a device is declaring the available entropy sources (...
