This document provides a summary of public key encryption and digital signatures. It begins by reviewing symmetric cryptography and its limitations in key distribution. It then introduces public key encryption, where each party has a public and private key pair. The document outlines the RSA algorithm and how it uses large prime number factorization problems to encrypt and decrypt messages. It also discusses how digital signatures can provide authentication, integrity, and non-repudiation for electronic messages and contracts using public key techniques like RSA.
This document discusses the RSA cryptosystem, including an overview of symmetric and asymmetric key algorithms, the founders of RSA, the RSA key generation algorithm in 5 steps, estimated times to crack RSA keys of different sizes, possible side-channel attacks on RSA, tutorials on implementing RSA, and references for further reading. It provides information on the basic concepts and implementation of the RSA cryptosystem.
This document summarizes public-key cryptography. It discusses how public-key cryptography uses unique public and private keys to encrypt and decrypt messages securely. It describes how public-key encryption allows a sender to encrypt a message with the recipient's public key, while only the recipient's private key can decrypt it. It also explains how digital signatures allow a sender to encrypt a message with their private key for authentication, while the recipient can decrypt it with the sender's public key to verify identity and integrity. The document notes some vulnerabilities of public-key cryptography like longer key sizes and man-in-the-middle attacks, and how certificate authorities help address these issues.
The document discusses the RSA algorithm for public-key cryptography. It explains that RSA uses a public key and private key pair, where the public key is used to encrypt messages and the private key is used to decrypt them. The security of RSA relies on the difficulty of factoring large prime numbers. It describes how the RSA algorithm works by choosing two prime numbers to generate keys, how encryption and decryption are performed using modular exponentiation, and factors that influence the security of RSA implementations.
This document provides a comparative analysis of the RSA and MD5 algorithms. It discusses the basics of cryptography and describes how MD5 works to generate a 128-bit hash value from a variable-length message using four rounds of processing. The document also compares different versions of MD5 (MD2, MD4, MD5) and describes how RSA uses a public/private key pair to enable secure communication.
Este documento describe dos criptosistemas clásicos de clave pública: ElGamal y Massey-Omura. El criptosistema ElGamal se basa en la función unidireccional exponencial discreta y su seguridad depende de la dificultad del problema del logaritmo discreto. El documento explica los pasos de generación de claves, cifrado y descifrado para ElGamal. También presenta el criptosistema alternativo de Massey-Omura.
This document provides a summary of public key encryption and digital signatures. It begins by reviewing symmetric cryptography and its limitations in key distribution. It then introduces public key encryption, where each party has a public and private key pair. The document outlines the RSA algorithm and how it uses large prime number factorization problems to encrypt and decrypt messages. It also discusses how digital signatures can provide authentication, integrity, and non-repudiation for electronic messages and contracts using public key techniques like RSA.
This document discusses the RSA cryptosystem, including an overview of symmetric and asymmetric key algorithms, the founders of RSA, the RSA key generation algorithm in 5 steps, estimated times to crack RSA keys of different sizes, possible side-channel attacks on RSA, tutorials on implementing RSA, and references for further reading. It provides information on the basic concepts and implementation of the RSA cryptosystem.
This document summarizes public-key cryptography. It discusses how public-key cryptography uses unique public and private keys to encrypt and decrypt messages securely. It describes how public-key encryption allows a sender to encrypt a message with the recipient's public key, while only the recipient's private key can decrypt it. It also explains how digital signatures allow a sender to encrypt a message with their private key for authentication, while the recipient can decrypt it with the sender's public key to verify identity and integrity. The document notes some vulnerabilities of public-key cryptography like longer key sizes and man-in-the-middle attacks, and how certificate authorities help address these issues.
The document discusses the RSA algorithm for public-key cryptography. It explains that RSA uses a public key and private key pair, where the public key is used to encrypt messages and the private key is used to decrypt them. The security of RSA relies on the difficulty of factoring large prime numbers. It describes how the RSA algorithm works by choosing two prime numbers to generate keys, how encryption and decryption are performed using modular exponentiation, and factors that influence the security of RSA implementations.
This document provides a comparative analysis of the RSA and MD5 algorithms. It discusses the basics of cryptography and describes how MD5 works to generate a 128-bit hash value from a variable-length message using four rounds of processing. The document also compares different versions of MD5 (MD2, MD4, MD5) and describes how RSA uses a public/private key pair to enable secure communication.
Este documento describe dos criptosistemas clásicos de clave pública: ElGamal y Massey-Omura. El criptosistema ElGamal se basa en la función unidireccional exponencial discreta y su seguridad depende de la dificultad del problema del logaritmo discreto. El documento explica los pasos de generación de claves, cifrado y descifrado para ElGamal. También presenta el criptosistema alternativo de Massey-Omura.
This document provides an overview of classical encryption techniques. It begins with definitions of key terms like plaintext, ciphertext, encryption, and decryption. It then describes the symmetric cipher model and simplifies it. The document outlines areas of cryptography and cryptanalysis. It explains techniques like substitution ciphers, the Caesar cipher, monoalphabetic ciphers, the Playfair cipher, the Hill cipher, polyalphabetic ciphers, and the one-time pad cipher. For each technique, it provides a brief description and encryption algorithm.
For a college course -- CNIT 141: Cryptography for Computer Networks, at City College San Francisco
Based on "Serious Cryptography: A Practical Introduction to Modern Encryption", by Jean-Philippe Aumasson, No Starch Press (November 6, 2017), ISBN-10: 1593278268 ISBN-13: 978-1593278267
Instructor: Sam Bowne
More info: https://samsclass.info/141/141_S19.shtml
Principles of public key cryptography and its UsesMohsin Ali
This document discusses the principles of public key cryptography. It begins by defining asymmetric encryption and how it uses a public key and private key instead of a single shared key. It then discusses key concepts like digital certificates and public key infrastructure. The document also provides examples of how public key cryptography can be used, including the RSA algorithm and key distribution methods like public key directories and certificates. It explains how public key cryptography solves the key distribution problem present in symmetric encryption.
The document defines various terms related to encryption and decryption such as encryption, decryption, cryptosystem, plaintext, and ciphertext. It describes different types of encryption algorithms including symmetric encryption which uses the same key for encryption and decryption, and asymmetric encryption which uses different keys. It also explains different encryption methods such as substitution ciphers including monoalphabetic and polyalphabetic substitutions as well as transposition ciphers. The Caesar cipher and Vigenère cipher are provided as examples. Factors that can be analyzed to cryptanalyze ciphers are also outlined.
A project which implements the Elliptic Curve Cryptography for the Diffie-Hellman keys exchange, in order to establish a secure channel between two Android devices.
Public Key Cryptosystems with Applications, Requirements and
Cryptanalysis, RSA algorithm, its computational aspects and security, Diffie-Hillman Key Exchange algorithm, Man-in-Middle attack
Modern block ciphers are widely used to provide encryption of quantities of information, and/or a cryptographic checksum to ensure the contents have not been altered. We continue to use block ciphers because they are comparatively fast, and because we know a fair amount about how to design them.
This document discusses public key cryptography and the RSA algorithm. It begins by outlining some misconceptions about public key encryption. It then provides an overview of the key concepts behind public key cryptosystems, including the use of public and private key pairs to enable encryption, digital signatures, and key exchange. The document goes on to provide detailed explanations of the RSA algorithm, including how it uses large prime numbers and modular arithmetic to encrypt and decrypt messages securely. It discusses the security of the RSA algorithm and analyzes approaches for attacking it, such as brute force key searching and mathematical attacks based on factoring the private key.
Introduction to homomorphic encryption, encryption which allows computations on ciphertext. An overview of key aspects and the ideas that allow these schemes to work is given, as well as examples of how to apply it.
Christoph Matthies (@chrisma0), Hubert Hesse (@hubx), Robert Lehmann (@rlehmann)
Public Key Cryptography and RSA algorithmIndra97065
Public Key Cryptography and RSA algorithm.Explanation and proof of RSA algorithm in details.it also describer the mathematics behind the RSA. Few mathematics theorem are given which are use in the RSA algorithm.
The document discusses the RSA and MD5 algorithms. It provides an overview of how RSA works, including key generation, encryption, and decryption. It also explains the MD5 hashing algorithm and its use in ensuring data integrity. Both algorithms are commonly used in security and encryption applications.
SSL uses TCP to provide a secure end-to-end service. It consists of two layers - the SSL record protocol and the SSL handshake protocol. The record protocol provides data encryption and integrity checking, while the handshake protocol allows the server and client to authenticate each other and negotiate encryption parameters for the secure connection.
BUD17-302: LLVM Internals #2
Speaker: Renato Golin, Peter Smith, Diana Picus, Omair Javaid, Adhemerval Zanella
Track: Toolchain
★ Session Summary ★
Continuing from LAS16 and, if we have time, introducing global isel that we’re working on.
---------------------------------------------------
★ Resources ★
Event Page: http://connect.linaro.org/resource/bud17/bud17-302/
Presentation:
Video:
---------------------------------------------------
★ Event Details ★
Linaro Connect Budapest 2017 (BUD17)
6-10 March 2017
Corinthia Hotel, Budapest,
Erzsébet krt. 43-49,
1073 Hungary
---------------------------------------------------
http://www.linaro.org
http://connect.linaro.org
---------------------------------------------------
Follow us on Social Media
https://www.facebook.com/LinaroOrg
https://twitter.com/linaroorg
https://www.youtube.com/user/linaroorg?sub_confirmation=1
https://www.linkedin.com/company/1026961
"
Attribute Based Encryption with Privacy Preserving In Clouds Swathi Rampur
This is a ppt made by shrihari ,in this encryption with privacy preserving in clouds is described!
It will be helpfull for those who are doing projects on cloud!
Kernel developers may have experience in writing makefiles for the linux kernel. In many cases, maybe just adding lines like
"obj-$(CONFIG_FOO) += foo.o" to a makefile. But, probably there
is not many people really know what's going on behind this cool
build system.
In this talk, Cao jin will dive into the Kbuild internals. Starting from
the basics of GNU Make, he will explain how Kbuild works, and in the end, produces vmlinux, bzImage, modules. The talk will also focus on some smart tricks used in Kbuild. At last, he will give a introduction about how Xen project is related with this config/build system.
The document discusses using the RSA algorithm to provide data security in cloud computing. It begins with an objective to ensure security and optimize encryption/decryption time using RSA. It then provides background on cloud computing and the need for security. It describes the RSA algorithm, including key generation, encryption, and decryption. It also discusses a proposed method to improve data security and decrease execution time by increasing key length.
This document provides an overview of classical encryption techniques. It begins with definitions of key terms like plaintext, ciphertext, encryption, and decryption. It then describes the symmetric cipher model and simplifies it. The document outlines areas of cryptography and cryptanalysis. It explains techniques like substitution ciphers, the Caesar cipher, monoalphabetic ciphers, the Playfair cipher, the Hill cipher, polyalphabetic ciphers, and the one-time pad cipher. For each technique, it provides a brief description and encryption algorithm.
For a college course -- CNIT 141: Cryptography for Computer Networks, at City College San Francisco
Based on "Serious Cryptography: A Practical Introduction to Modern Encryption", by Jean-Philippe Aumasson, No Starch Press (November 6, 2017), ISBN-10: 1593278268 ISBN-13: 978-1593278267
Instructor: Sam Bowne
More info: https://samsclass.info/141/141_S19.shtml
Principles of public key cryptography and its UsesMohsin Ali
This document discusses the principles of public key cryptography. It begins by defining asymmetric encryption and how it uses a public key and private key instead of a single shared key. It then discusses key concepts like digital certificates and public key infrastructure. The document also provides examples of how public key cryptography can be used, including the RSA algorithm and key distribution methods like public key directories and certificates. It explains how public key cryptography solves the key distribution problem present in symmetric encryption.
The document defines various terms related to encryption and decryption such as encryption, decryption, cryptosystem, plaintext, and ciphertext. It describes different types of encryption algorithms including symmetric encryption which uses the same key for encryption and decryption, and asymmetric encryption which uses different keys. It also explains different encryption methods such as substitution ciphers including monoalphabetic and polyalphabetic substitutions as well as transposition ciphers. The Caesar cipher and Vigenère cipher are provided as examples. Factors that can be analyzed to cryptanalyze ciphers are also outlined.
A project which implements the Elliptic Curve Cryptography for the Diffie-Hellman keys exchange, in order to establish a secure channel between two Android devices.
Public Key Cryptosystems with Applications, Requirements and
Cryptanalysis, RSA algorithm, its computational aspects and security, Diffie-Hillman Key Exchange algorithm, Man-in-Middle attack
Modern block ciphers are widely used to provide encryption of quantities of information, and/or a cryptographic checksum to ensure the contents have not been altered. We continue to use block ciphers because they are comparatively fast, and because we know a fair amount about how to design them.
This document discusses public key cryptography and the RSA algorithm. It begins by outlining some misconceptions about public key encryption. It then provides an overview of the key concepts behind public key cryptosystems, including the use of public and private key pairs to enable encryption, digital signatures, and key exchange. The document goes on to provide detailed explanations of the RSA algorithm, including how it uses large prime numbers and modular arithmetic to encrypt and decrypt messages securely. It discusses the security of the RSA algorithm and analyzes approaches for attacking it, such as brute force key searching and mathematical attacks based on factoring the private key.
Introduction to homomorphic encryption, encryption which allows computations on ciphertext. An overview of key aspects and the ideas that allow these schemes to work is given, as well as examples of how to apply it.
Christoph Matthies (@chrisma0), Hubert Hesse (@hubx), Robert Lehmann (@rlehmann)
Public Key Cryptography and RSA algorithmIndra97065
Public Key Cryptography and RSA algorithm.Explanation and proof of RSA algorithm in details.it also describer the mathematics behind the RSA. Few mathematics theorem are given which are use in the RSA algorithm.
The document discusses the RSA and MD5 algorithms. It provides an overview of how RSA works, including key generation, encryption, and decryption. It also explains the MD5 hashing algorithm and its use in ensuring data integrity. Both algorithms are commonly used in security and encryption applications.
SSL uses TCP to provide a secure end-to-end service. It consists of two layers - the SSL record protocol and the SSL handshake protocol. The record protocol provides data encryption and integrity checking, while the handshake protocol allows the server and client to authenticate each other and negotiate encryption parameters for the secure connection.
BUD17-302: LLVM Internals #2
Speaker: Renato Golin, Peter Smith, Diana Picus, Omair Javaid, Adhemerval Zanella
Track: Toolchain
★ Session Summary ★
Continuing from LAS16 and, if we have time, introducing global isel that we’re working on.
---------------------------------------------------
★ Resources ★
Event Page: http://connect.linaro.org/resource/bud17/bud17-302/
Presentation:
Video:
---------------------------------------------------
★ Event Details ★
Linaro Connect Budapest 2017 (BUD17)
6-10 March 2017
Corinthia Hotel, Budapest,
Erzsébet krt. 43-49,
1073 Hungary
---------------------------------------------------
http://www.linaro.org
http://connect.linaro.org
---------------------------------------------------
Follow us on Social Media
https://www.facebook.com/LinaroOrg
https://twitter.com/linaroorg
https://www.youtube.com/user/linaroorg?sub_confirmation=1
https://www.linkedin.com/company/1026961
"
Attribute Based Encryption with Privacy Preserving In Clouds Swathi Rampur
This is a ppt made by shrihari ,in this encryption with privacy preserving in clouds is described!
It will be helpfull for those who are doing projects on cloud!
Kernel developers may have experience in writing makefiles for the linux kernel. In many cases, maybe just adding lines like
"obj-$(CONFIG_FOO) += foo.o" to a makefile. But, probably there
is not many people really know what's going on behind this cool
build system.
In this talk, Cao jin will dive into the Kbuild internals. Starting from
the basics of GNU Make, he will explain how Kbuild works, and in the end, produces vmlinux, bzImage, modules. The talk will also focus on some smart tricks used in Kbuild. At last, he will give a introduction about how Xen project is related with this config/build system.
The document discusses using the RSA algorithm to provide data security in cloud computing. It begins with an objective to ensure security and optimize encryption/decryption time using RSA. It then provides background on cloud computing and the need for security. It describes the RSA algorithm, including key generation, encryption, and decryption. It also discusses a proposed method to improve data security and decrease execution time by increasing key length.
3. Giriş
1985’te Taher Elgamal tarafından tasarlanmış Diffie Hellman
algoritmasına dayanan asimetrik şifreleme algoritmasıdır.
Temel olarak ayrık algoritma ve dairesel gruplardan oluşur.
Hem veri şifreleme hem de sayısal imza yapabilir.
3 aşamadan meydana gelir: Anahtar oluşturma, şifreleme, deşifreleme.
4. Algoritma Açıklaması
P, k, g ve x sayıları
kullanılarak y =g^x
mod(p) değeri
hesaplanır.
Açık anahtar olarak k,
y, g ve p değişkenleri
tüm vericilere
ulaştırılabilir.
Gizli anahtar olarak
kullanılacak x
değişkeni, alıcıda
saklanmalıdır.
Verici, M
(şifrelenmemiş mesaj)
mesajını şifrelemek
istediğinde belirtilen
işlemleri yapar.
Bu işlemler sonucunda
C₁ ve C₂ şifreli
metinleri oluşur.
C₁=g^k mod(p)
C₂=y^k * M mod(p)
5. Algoritma Açıklaması
Alıcıya ulaştıracağımız C₁ ve C ₂ şifreli metinlerini
kullanarak aşağıdaki işlemi yapıp düz metin olan M
mesajı elde edilir.
M= C₂/C₁* mod(p)
Elgamal algoritmasında sağlamlık seçilecek olan açık ve
gizli anahtarların rastgeleliğine ve değerlerin büyüklüğü
ile ilgilidir.
Bir örnek ile bu 3 aşamayı işleyelim.
6. Anahtar Oluşturma
“p” asal sayısı
belirlenir.
(p-1) ile aralarında
asal olacak bir k
sayısı belirlenir.
P’den küçük
olacak şekilde
birbirlerinden
farklı g ve x
sayıları belirlenir.
Bu değerler
kullanılarak
y = g*mod(p)
hesaplanır.
p, g ve y değerleri
public key olarak
yayınlanır.
ElGamal Oluşturma Örneği:
1. p=23 olsun.
2. Primitive element g=11
3. Private key x=6 olarak seçelim.
4. y=11⁶(mod 23) =9
Public key: 9
Private key: 6
7. Şifreleme
2.aşamada M
mesajını şifrelemek
için gerekli işlemler
yapılır.
Şifreli metinleri
hesaplamak için
aşağıdaki adımlar
gerçekleştirilir:
C₁=g^k mod(p) C₂=y^k M mod(p)
ElGamal Şifreleme Örneği:
Public key 9 ile M=10 ’u şifrelemek için
1. Rastgele k=3 oluşturun.
2. C₁=11³ mod 23=20
C₂=10 x 9³ mod 23
=10 x 16 = 160 mod 23=22
3. Ciphertext C= (20, 22)
8. Deşifreleme
Mesajı alan tarafın şifreli mesajı
açması için:
M = C₂/C₁^x mod(p)
ElGamal Deşifreleme Örneği:
C=(20, 22) şifrelemek için,
1. Hesaplama 20⁴=16 mod 23 hesaplayın.
2. Hesaplama 22 /16=10 mod 23
3. Plaintext = 10
9. Kaynakça
1. Çetinkaya,H. (2019) RSA ve Elgamal Kismi Homomorfik Kripto Sistemlerin Vergi Ödeme Sistemine
Uygulanması ve Bu Uygulamaların Performans Analizleri. YÖK Tez Merkezi , 20-100
2. Paar C., Pelzl J. (2010). Understanding Cryptography, Springer. (s.226- 246)
3. Hoşcoşkun, R. E. (2020). Homomorfik Şifreleme Yöntemi Üzerine Bir İnceleme. Dspaca@Trakya
Kurumsal Akademik Arşiv, 60-70.
4. URL: https://www.researchgate.net/publication/340455167_ELGAMAL_SIFRELEME_ALGORITMASI