Main » TERM » C »

CHAP

Short for Challenge Handshake Authentication Protocol, a type of authentication in which the authentication agent (typically a network server) sends the client program a random value that is used only once and an ID value. Both the sender and peer share a predefined secret. The peer concatenates the random value (or nonce), the ID and the secret and calculates a one-way hash using MD5. The hash value is sent to the authenticator, which in turn builds that same string on its side, calculates the MD5 sum itself and compares the result with the value received from the peer. If the values match, the peer is authenticated.

By transmitting only the hash, the secret can't be reverse-engineered. The ID value is increased with each CHAP dialogue to protect against replay attacks.

Contrast with PAP.







TECH RESOURCES FROM OUR PARTNERS
LATEST ARTICLES
Facts about Cloud Computing in 2017

The following facts and statistics capture the changing landscape of cloud computing and how service providers and customers are keeping up with... Read More »

Facts about Computer Science: Education and Jobs

The following computer science facts and statistics provides a quick introduction to the changing trends in education and related careers. Read More »

Text Messaging & Chat Abbreviations

From A3 to LOL and ZZZ this guide lists 1,500 text message and online chat abbreviations to help you translate and understand today's texting... Read More »

STUDY GUIDES
The Five Generations of Computers

Learn about each of the five generations of computers and major technology developments that have led to the computing devices that we use... Read More »

Computer Architecture Study Guide

Computer architecture provides an introduction to system design basics for most computer science students. Read More »

Network Fundamentals Study Guide

Networking fundamentals teaches the building blocks of modern network design. Learn different types of networks, concepts, architecture and... Read More »