Three-pass protocol

Asymmetric-key algorithms

In cryptography, a three-pass protocol for sending messages is a framework which allows one party to securely send a message to a second party without the need to exchange or distribute encryption keys. Such message protocols should not be confused with various other algorithms which use 3 passes for authentication. It is called a three-pass protocol because the sender and the receiver exchange three encrypted messages. The first three-pass protocol was developed by Adi Shamir circa 1980, and is described in more detail in a later section. The basic concept of the three-pass protocol is that each party has a private encryption key and a private decryption key. The two parties use their keys independently, first to encrypt the message, and then to decrypt the message. The protocol uses an encryption function E and a decryption function D. The encryption function uses an encryption key e to change a plaintext message m into an encrypted message, or ciphertext, . Corresponding to each encryption key e there is a decryption key d which allows the message to be recovered using the decryption function, . Sometimes the encryption function and decryption function are the same. In order for the encryption function and decryption function to be suitable for the three-pass protocol they must have the property that for any message m, any encryption key e with corresponding decryption key d and any independent encryption key k, . In other words, it must be possible to remove the first encryption with the key e even though a second encryption with the key k has been performed. This will always be possible with a commutative encryption. A commutative encryption is an encryption that is order-independent, i.e. it satisfies for all encryption keys a and b and all messages m. Commutative encryptions satisfy . The three-pass protocol works as follows: 1. * The sender chooses a private encryption key s and a corresponding decryption key t. The sender encrypts the message m with the key s and sends the encrypted message to the receiver. 2. * The receiver chooses a private encryption key r and a corresponding decryption key q and super-encrypts the first message with the key r and sends the doubly encrypted message back to the sender. 3. * The sender decrypts the second message with the key t. Because of the commutativity property described above which is the message encrypted with only the receiver's private key. The sender sends this to the receiver. The receiver can now decrypt the message using the key q, namely the original message. Notice that all of the operations involving the sender's private keys s and t are performed by the sender, and all of the operations involving the receiver's private keys r and q are performed by the receiver, so that neither party needs to know the other party's keys. (Wikipedia).

Stanford Seminar - The TLS 1.3 Protocol

"The TLS 1.3 Protocol" - Eric Rescorla of Mozilla and RTFM, Inc. About the talk: Transport Layer Security (TLS) is used for securing everything from Web transactions (HTTPS) to voice and video calls (DTLS-SRTP). However, the basic design of TLS dates back to the mid 1990s and the protocol

From playlist Engineering

System of Equations with Three Equations and Three Variables

Please Subscribe here, thank you!!! https://goo.gl/JQ8Nys System of Equations with Three Equations and Three Variables

From playlist Systems of Equations

Low Pass Filters & High Pass Filters : Data Science Concepts

What is a low pass filter? What is a high pass filter? Sobel Filter: https://en.wikipedia.org/wiki/Sobel_operator

From playlist Time Series Analysis

A10 Example problem of multiplicity three

An example problem of multiplicity three.

From playlist A Second Course in Differential Equations

5.4 HTTPS and TLSSSL

From playlist Internet Security for Beginners by Dr. Christoph Meinel

Multivariable Calculus | Three equations for a line.

We present three equations that represent the same line in three dimensions: the vector equation, the parametric equations, and the symmetric equation. http://www.michael-penn.net http://www.randolphcollege.edu/mathematics/

From playlist Lines and Planes in Three Dimensions

5.9 UDP

From playlist Internetworking with TCP/IP by Prof. Dr. Christoph Meinel

the Internet (part 2)

An intro to the core protocols of the Internet, including IPv4, TCP, UDP, and HTTP. Part of a larger series teaching programming. See codeschool.org

From playlist The Internet

How to Send a Secret Message

How do you send a secret message if someone might be eavesdropping? How can you give someone a locked box to open without giving them the key? Here, we take a look at the three-pass protocol and man-in-the-middle attacks. 0:00 Locks and Keys 1:20 Three-Pass Protocol 3:28 Man in the Middle

From playlist Spanning Tree Favorites

23C3: Design and Implementation of an object-oriented, secure TCP/IP Stack

Speakers: Andreas Bogk, Hannes Mehnert Ethereal^W Wireshark without remote exploits - a proof of concept We present a domain-specific language (DSL) capable to describe ad-hoc defined protocols like TCP/IP. Additionally we developed other libraries, like a flow graph for packet proce

From playlist 23C3: Who can you trust

1.4 TCP/IP Stack

From playlist Internetworking with TCP/IP by Prof. Dr. Christoph Meinel

ElixirConf 2016 - Implementing Binary Protocols with Elixir by Ole Michaelis

Implementing Binary Protocols with Elixir by Ole Michaelis Binary protocols are all around us, HTTP/2, HPACK, or DNS are only a few examples. Pretty efficient on the transport layer they reduce size dramatically and enable a set of great features. But they are often more complex to implem

From playlist ElixirConf 2016

DEFCON 15: Functional Fuzzing with Funk

Speaker: Benjamin Kurtz This talk will introduce a simple and incredibly powerful framework for the scripted generation of network traffic: Funk, a new tool for fuzzing arbitrary network protocols written using the Chicken Scheme-to-C compiler. Source code will be provided and explained,

From playlist DEFCON 15

Communications and Network Security | CISSP Training Videos

🔥 Enroll for FREE CISSP Course & Get your Completion Certificate: https://www.simplilearn.com/learn-cloud-security-basics-skillup?utm_campaign=CCSP&utm_medium=DescriptionFirstFold&utm_source=youtube Communication and Network Security : Domain 4 of the CISSP certification course offered by

From playlist Cyber Security Playlist [2023 Updated]🔥

DEFCON 16: Nail the Coffin Shut, NTLM is Dead

Speaker: Kurt Grutzmacher, Security Researcher Ever since SirDystic's SMBRelay release the weaknesses of the NTLM protocol have been repeatedly shown. For over twenty years this protocol has been refined by Microsoft, it's time to let it go and stop supporting it within our networks. Thi

From playlist DEFCON 16

Lecture 6: Protocols Shapes

Lecture 6 of Stanford’s CS193p SwiftUI development course given during the Spring of 2021 finished off the discussion of the Swift Type System with an explanation of perhaps the most important kind of type in Swift: protocols. We touch on a number of protocol concepts, including a "constra

From playlist CS193P Spring 2021

The nightmare future humanity avoided

The Montreal Protocol was designed to save the ozone layer, but it may have ended up saving the planet. Learn more about how the atmosphere absorbs radiation with Brilliant! https://www.brilliant.org/simonclark A new paper this year examined the "world avoided" via the Montreal Protocol,

From playlist Science videos

Network Security Tutorial For Beginners | Cybersecurity Training | Edureka | Cybersecurity Live - 3

🔥Edureka Cyber Security Course: https://www.edureka.co/cybersecurity-certification-training This Edureka video gives an introduction to Network Security and its nuances. It discusses the need of network security, tools for network security and various other fundamental concepts. 🔴Subscri

From playlist Edureka Live Classes 2020

Computer Networks. Part Six: The TCP/IP Protocol Stack and Routers

This is the sixth in a series about computer networks. This video describes the role of a network protocol, and specifically details the TCP/IP suite of protocols. The need for a layered approach to networking software is discussed including the four layer TCP/IP stack and the relevance

From playlist Computer Networks

Firewalls and Intrusion Detection Systems

Cryptography and Network Security by Prof. D. Mukhopadhyay, Department of Computer Science and Engineering, IIT Kharagpur. For more details on NPTEL visit http://nptel.iitm.ac.in

From playlist Computer - Cryptography and Network Security

Three-pass protocol

Related pages