< 1 2 3 >   Sort: Date

Illustration of DSA Algorithm: p,q=7,3
This section provides a tutorial example to illustrate how DSA digital signature algorithm works with small prime modulus p=7 and prime divisor q=3.
2018-04-24, 2342👍, 5💬

💬 2016-03-22 Herong: Peter, I see the issue now. This example needs to be reviewed and updated. Thanks for the feedback.

💬 2016-03-21 peter winzell: x is not selected according to 0 < x < q

💬 2015-10-19 Herong: Hi Marian, do you have a question about this tutorial?

💬 2015-10-18 Marian: when q=3 x = 5 # selected: 0 < x < q

What is ECB (Electronic CodeBook) Operation Mode?
This section describes what is ECB (Electronic CodeBook) Operation Mode - each plaintext block is encrypted independently without any input from other blocks.
2016-01-10, 2262👍, 2💬

💬 2016-01-10 Todd: Thanks!

What Is Cryptography?
This section describes what is cryptography - The study of techniques related to all aspects of data security.
2017-02-18, 2127👍, 5💬

💬 2017-02-18 gabu: ggoodd

💬 2016-11-17 mohamed: yes

💬 2015-10-20 Herong: Hi Ian, the Rail Fence cipher is very simple example of encryption we can do manually. See the Transposition cipher page at wiki...

💬 2015-10-19 Ian T. Lee: Can you give me a simple example of how to do cryptography manually?

💬 2015-08-06 arnav: good

Introduction of DSA (Digital Signature Algorithm)
This chapter provides tutorial notes and example codes on DSA (Digital Signature Algorithm). Topics include introduction of DSA; illustration of DSA key generation, message signing and signature verification; proof of Digital Signature Algorithm.
2018-04-07, 2072👍, 11💬

💬 2018-04-07 Digital Signature Algorithm: Conclusions: DSA (Digital Signature Algorithm) uses public key and private key to generate and verify digital signatures. DSA pu...

💬 2018-04-07 Submit Your Comment: Please write meaningful comments. Thanks! ☺

💬 2018-04-07 world: hello

💬 2018-02-20 amit: hello

💬 2017-09-19 dasu: we r champion

Cryptography Terminology
This section provides descriptions on some commonly used cryptography terminologies
2015-10-24, 2062👍, 1💬

💬 2015-10-24 dexter aparicio: this site is my favorite reference on cryptography topics

Subkeys of 3DES Encryption
Hi Doc, I have subkeys recovered through DPA. Can 3DES.c be modified to accept these subkeys as inputs for a cryptographic operation? Alternatively, can the main 3DES key be reverse generated from the subkeys? Thanks. jeffrey****alis@gmail.com
2015-07-23, 1977👍, 1💬

💬 2015-07-22 Herong: Hi Jeffrey, Which 3DES.c are you referring to? Can you tell me where I can see the code?

Cryptography Basic Concepts
This chapter describes some basic concepts of cryptography: what is cryptography, what is function and what is encryption.
2016-04-07, 1896👍, 4💬

💬 2016-02-03 dinesh: thanks

💬 2015-12-28 Herong: Malini, RSA is good example of cryptosystem. Read Introduction of RSA Algorithm for more information.

💬 2015-12-28 malini: need cryptosystem

DES Key Schedule Algorithm Illustration Program Output
This section provides the execution output of the tutorial Java program, DESSubkeysTest.java, to illustrate how DES key schedule algorithm works.
2015-08-09, 1613👍, 1💬

💬 2015-08-08 nishant nath: I loved it

What is CFB (Cipher FeedBack) Operation Mode?
This section describes what is CFB (Cipher FeedBack) Operation Mode - each plaintext block is XORed with the encrypted version of the ciphertext of the previous block to be the ciphertext block.
2017-01-13, 1594👍, 3💬

💬 2016-12-07 fakhrulislam: i want a copy of this book !

💬 2015-11-06 poonam: a perfect explanation

SHA1 Mesasge Digest Algorithm
This chapter provides tutorial notes and example codes on the SHA1 message digest algorithm. Topics include SHA1 algorithm overview; using SHA1 in Java, PHP, and Perl.
2016-11-05, 1389👍, 5💬

💬 2015-10-14 Herong: Yojana, information on key generation of Blowfish Algorithm can be found in Key Schedule (Sub-Keys Generation) Algorithm tutoria...

💬 2015-10-13 Yojana Yadav: Plz send me the detail of key generation of Blowfish Algorithm

💬 2013-06-28 Herong: Abbas, You are welcome!

💬 2013-06-26 abbas: thank you for sha-1 and it's so helpful

RsaKeyGenerator.java for RSA Key Generation
This section describes the initial draft of a RSA public key and private key generation implementation using the java.math.BigInteger class.
2017-01-05, 1386👍, 2💬

💬 2017-01-05 Herong: Alex, you are right. q should be selected independently from p. I will make a change in the next revision.

💬 2016-12-28 Alex T.: Using nextProbablePrime() to compute q appears somewhat risky to me: An attacker with the knowledge of N=p*q could simply comput...

Viewing Components of RSA Keys
This section provides a tutorial example on how to view different components of a pair of RSA private key and public key using the OpenSSL command line tool.
2016-03-14, 1385👍, 2💬

💬 2015-10-02 Herong: Looks like someone is testing Base64 encoding here :-)

💬 2015-10-01 1: CSENry/M1h2AhxGSxQluy4b1ynzBGWeO320C AwEAAQJAbQQn... IQCoo0AdFXm789FfHuB+mVIKNtBLTAQNaMuX z6lXl7Ib7Q==

What is OFB (Output FeedBack) Operation Mode?
This section describes what is OFB (Output FeedBack) Operation Mode - each plaintext block is XORed with the current output block to be the ciphertext block. The current output block is the encrypted version of the previous output block.
2015-11-13, 1271👍, 2💬

💬 2015-11-13 Ashish: Hello world!

PHP Implementation of DES - mcrypt
This chapter provides tutorial examples and notes about PHP implementation of DES. Topics include introduction of mcrypt library; mcrypt encryption functions; DES encryption and decryption test program and test result.
2017-11-23, 1238👍, 3💬

💬 2016-01-02 sivaprakash: nice

Using Certificates in Firefox
This chapter provides tutorial notes and example codes on using certificates in Firefox 18. Topics include why Web browsers need certificates; viewing the certificate from an https Web server; exporting a certificate from Firefox 18 to a certificate file; importing a CA certificate into Firefox 18.
2017-08-31, 1068👍, 1💬

💬 2017-08-31 bobby: ok will do

Illustration of RSA Algorithm: p,q=7,19
This section provides a tutorial example to illustrate how RSA public key encryption algorithm works with 2 small prime numbers 7 and 19.
2016-02-29, 991👍, 3💬

💬 2015-11-01 Herong: Jun, AES algorithm is added now, see Introduction to AES (Advanced Encryption Standard).

💬 2015-10-17 Herong: Jun, thank you for pointing out the mistake. I will correct it in the next version. AES will also be included.

💬 2015-10-16 jun: thanks a lot. your book makes everything clear for me except that I have not found a char for AES. By the way, I think "Generati...

Key Schedule (Sub-Keys Generation) Algorithm
This section describes the Blowfish Key Schedule (Sub-Keys Generation) algorithm. It uses the binary representation of the fractional portion of constant Pi - 3.1415927... as initial values.
2016-03-17, 977👍, 2💬

💬 2016-03-17 Herong: Hi Yogita, Blowfish(T) function refers the Blowfish algorithm described in the previous tutorial: Blowfish Cipher Algorithm.

💬 2016-03-16 YOGITA: what is the function blowfish(T) here? Send the pseudo code

Generating New RSA Key Pairs
This section provides a tutorial example on how to generate a new pair of RSA priviate key and public key using the OpenSSL command line tool.
2015-11-03, 798👍, 1💬

💬 2015-11-03 Juli: Thanks

Key Pair Sample Program - JcaKeyPair.java
This section provides a tutorial example on how to write simple program to generate a pair of private key and public key for the RSA or DSA algorithm.
2016-03-01, 717👍, 1💬

💬 2016-03-01 Shruti: thanks

OpenSSL Introduction and Installation
This chapter provides tutorial notes and example codes on OpenSSL. Topics include introduction of OpenSSL; installing OpenSSL on Windows systems.
2017-12-24, 697👍, 4💬

💬 2016-11-28 musa: thanks

DESCipherTest.java - DES Cipher Algorithm Illustration
This section provides a tutorial Java program, DESCipherTest.java, to illustrate how DES cipher algorithm works.
2016-01-24, 677👍, 1💬

💬 2016-01-24 Joe: Output

MD5 Mesasge Digest Algorithm
This chapter provides tutorial notes and example codes on the MD5 message digest algorithm. Topics include MD5 algorithm overview; using MD5 in Java, PHP, and Perl.
2017-09-10, 669👍, 2💬

💬 2016-05-19 ishvar: hello ahemad

Steps of Using DES Algorithm in JDK JCE
This section describes how to use DES algorithm provided in the JDK JCE package. Steps include building a secret key object from key material; creating and initializing a cipher object.
2016-01-24, 658👍, 1💬

💬 2016-01-24 Joe: Very nice

mcrypt DES Encryption Testing Program
This section provides a tutorial example on how to use the DES algorithm in a specific operation mode as block or stream cipher.
2017-08-03, 626👍, 3💬

💬 2017-08-03 Herong: Deepan, Which part is difficult for you to understand?

💬 2017-07-27 Deepan: I can't understand

< 1 2 3 >   Sort: Date