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### Is a RSA 2048 bits public key secure [duplicate]

I realize servers such as Google, Yahoo, which use RSA has 2048 bits public key. After comparing those keys, I realize that the public keys share a common property, that is first 9 bytes and last 5 ...
68 views

### Minimum length of PKI key for signature [duplicate]

I am looking for data which shows how time it would take to brute force (or crack by any other method) different sizes of RSA/DSA keys used for a digital signature. I am looking to use as small a ...
13k views

### Now that quantum computers have been out for a while, has RSA been cracked?

D-wave systems has released a commercially viable quantum computer. This means in theory, that all asymmetric encryption algorithms — such as RSA — are now useless due to the speed at which quantum ...
27k views

### Security strength of RSA in relation with the modulus size

NIST SP 800-57 §5.6.1 p.62–64 specifies a correspondence between RSA modulus size $n$ and expected security strength $s$ in bits: ...
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### How much computing resource is required to brute-force RSA?

It's been over 30 years since Rivest, Shamir and Adleman first publicly described their algorithm for public-key cryptography; and the intelligence community is thought to have known about it for ...
9k views

### Should I use RSA encryption since RSA is said to be broken by NSA?

I am developing a simple web app that uses asymmetric encryption, but I am not sure whether to chose RSA for the reasons mentioned above. What are your suggestions? Also if I decided to go with RSA ...
11k views

### Is 512-bit RSA still safe for signature generation?

The standard CSP on Windows XP only supports RSA up to 512-bit, which means that it's the maximum key size I can use for authenticity verification of updates. The public key is embedded in the updater,...
26k views

### How much stronger is RSA-2048 compared to RSA-1024?

How much stronger is RSA-2048 compared to RSA-1024? It is hard to imagine very big numbers. So what would be your way to explain the difference to someone who doesn't know much about cryptography?
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### What is the history of recommended RSA key sizes?

One can find up to date recommended key sizes for RSA at NIST sp800-131A for example. In short, it suggests a key size of at least 2048 bits. Is it possible to find a history of recommended key sizes ...
21k views

### What is the largest bit RSA encryption to be cracked?

This article shows a 4096 bit key being cracked by using a microphone and listening to your computer's cpu. I do not know if this is true at all. I am doing a presentation on RSA Security and I ...
1k views

### Are there any signature schemes for underpowered devices (8-bit microcontroller)?

I am currently researching into a small scale home automation system, aiming for cost. The system architecture is basically one master and several slaves which are connected in parallel. Recently i'...
3k views

### Should RSA primes p and q differ in length by "a few digits"?

When generating RSA keys in the original RSA paper it is stated: to gain additional protection against sophisticated factoring algorithms, p and q should differ in length by a few digits Why is ...
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### How exactly are public and private keys used to encrypt and the decrypt data?

In asymmetric encryption schemes, a public key is used by an outside source to encrypt data to be sent to the holder of the private key. It's my understanding that public keys are generated from the ...
1k views

### Could a fixed RSA encryption be used instead of a salt to prevent rainbow table attacks?

It's common to use a salt before hashing a password in order to prevent an attack by rainbow tables. Would it also work to encrypt the password for instance by RSA encryption - by a permanent RSA ...
2k views

### When was the RSA 64-bit key introduced into internet encryption?

When (if ever) was a key length of 64 bits used in "internet encryption" and when was that "cryptographic standard" first introduced? Following up, when did "internet encryption" key lengths change ...
8k views

### How long to bruteforce a RSA key [duplicate]

Suppose I have a 2048 bit RSA public key, and want to brute force the corresponding private key. I guess there are 2048^16 possible combinations? How long would this take me to brute force with an i7,...
1k views

### RSA time function

I am doing a paper on textbook RSA (highschool-level). I am explaining and proving the significance of the public key exponent in time and security. So far, I have encrypted a constant message with a ...
1k views

### Security of RSA for paranoids with padding?

RSA for Paranoids (RSAP) (in CryptoBytes v1n3), also known as Unbalanced RSA, is a variant of RSA proposed in 1995 by Adi Shamir, as a mean to increase the RSA public modulus size while keeping ...
1k views

### Why are recomended RSA key lengths so high? [duplicate]

I was checking for authoritative sources to back up my recommendation of a minimum RSA key length of 1024 and was shocked to find that NIST 800-56Br1 and FIPS 186-4 both recommend at least 2048 bits ...
1k views

### Prime factorization of 700 decimal digits number

I'm a newbie to encryption. If I create a number 'n' as a product of two prime numbers 'p' and 'q' with the following specifications: 'p' is a fully random prime with 300 decimal digits in length. 'q'...
1k views

### Practical Attack on RSA

Currently I am designing an RSA based application, and I am thinking of how long should the key be in order to be secure against attacks. I know that RSA 4096 bit key can be recovered using Sound ...
1k views

### Sign MD5 hash with RSA [duplicate]

I have to hash a message with MD5, digitally sign it, and then verify. I have looked around, but I can't find a step-by-step example. I understand how RSA works when a message is given as number (not ...
1k views

### How should I address message size limits in RSA encryption?

I am making an end-to-end encryption software program in Java using RSA. I am using BigIntegers and its number theory methods. (I know this is a very slow approach, but I just want to learn to the ...
565 views

### Distributed integer factorization?

I'm looking around for publicly published work on factorization of large numbers using distributed systems of any kind. So far I've come across the PDF "Mapreduce for integer factorization" by Javier ...
428 views

### 80-bit security and attack time

Many designer claimed that their cryptography scheme has 80-bit security. So how to calculate the time of attcking this 80-bit security cryptography scheme, such as 80-bit security RSA using a kind of ...
845 views

### RSA finding p and q integer with condition

I'm given $N=p\,q$ and told that $44\,p\approx 17\,q$ (with the value given for $N$ some 49-digit integer 8124642558124642555899928124642555899924479992447). In ...
843 views

### Small Encryption Exponent

I am trying to crack an unpadded RSA set up for a homework. I have public key (R,e) and encrypted message E. ...
645 views

### Rsa encryption security

What tool is used to measure the security of rsa encryption? If no, is there any tool to measure rsa encryption in terms of security. Or any idea how to measure security of rsa encryption?
$K_{pub} = (n, e)$ $K_{pvt} = d$ Then $E_{K_{pub}}(x) \equiv x^e \mod n$ Practically, when RSA is used to encrypt strings, what is the $x$ here? You cannot take it byte by byte because $\mod n$ will ...