Theory of cryptography

Semantic security

In cryptography, a semantically secure cryptosystem is one where only negligible information about the plaintext can be feasibly extracted from the ciphertext. Specifically, any probabilistic, polynomial-time algorithm (PPTA) that is given the ciphertext of a certain message (taken from any distribution of messages), and the message's length, cannot determine any partial information on the message with probability non-negligibly higher than all other PPTA's that only have access to the message length (and not the ciphertext). This concept is the computational complexity analogue to Shannon's concept of perfect secrecy. Perfect secrecy means that the ciphertext reveals no information at all about the plaintext, whereas semantic security implies that any information revealed cannot be feasibly extracted. (Wikipedia).

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IP Security: Part 1

Fundamental concepts of IPSec are discussed. Authentication Header is explained. ESP & IKE are analyzed.

From playlist Network Security

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Network Security, Part 1 : Basic Encryption Techniques

Fundamental concepts of network security are discussed. It provides a good overview of secret Key and public key Encryption. Important data encryption standards are presented.

From playlist Network Security

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IP Security: Part 2

Fundamental concepts of IPSec are discussed. Authentication Header is explained. Encapsulating Security Payload (ESP) and Internet Key Exchange (IKE) are analyzed.

From playlist Network Security

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Transport Layer Security: Part 2 - TLS & HTTPS

Fundamental concepts of TLS are discussed. SSL is analyzed. HTTPS & SSH are presented.

From playlist Network Security

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Internet Safety

If you are interested in learning more about this topic, please visit http://www.gcflearnfree.org/ to view the entire tutorial on our website. It includes instructional text, informational graphics, examples, and even interactives for you to practice and apply what you've learned.

From playlist The Internet

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Transport Layer Security: Part 1

Fundamental concepts of TLS are discussed. SSL is analyzed. HTTPS & SSH are presented.

From playlist Network Security

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Internet Safety: Your Browser's Security Features

In this video, you’ll learn more about your browser's security features. Visit https://www.gcflearnfree.org/internetsafety/your-browsers-security-features/1/ for our text-based lesson. This video includes information on: • Using browser security to check web addresses and identify securit

From playlist Internet Tips

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Digital Signatures: Part 1

Fundamental concepts of Digital Signatures are discussed. ElGamal and Schnorr Digital Signature schemes are analyzed. Digital signature standard is presented.

From playlist Network Security

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CERIAS Security: Semantic Attacks and Security 1/6

Clip 1/6 Speaker: Paul Thompson · Dartmouth College Attacks on computer and other networked systems can be categorized as physical, syntactic and semantic. Physical attacks seek to destroy hardware, while syntactic attacks, such as computer worms and viruses, target the network infras

From playlist The CERIAS Security Seminars 2006

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CERIAS Security: Toward Autonomic Security Policy Management 1/4

Clip 1/4 Speaker: Ehab Al-Shaer, Ph.D. · DePaul University, Chicago, IL The assurance of network security is dependent not only on the protocols but also on polices that determine the functional behavior of network security devices. Network security devices such as Firewalls, IPSec ga

From playlist The CERIAS Security Seminars 2006

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Lec 3 | Special Topics in Supply Chain Management

The Internet of Things: A Quantum Leap Forward Speakers: Steve Bratt, W3C; John Williams, MIT; Bernie Hogan, GS1 US View the complete course at: http://ocw.mit.edu/ESD-290S05 License: Creative Commons BY-NC-SA More information at http://ocw.mit.edu/terms More courses at http://ocw.mit.edu

From playlist MIT ESD.290 Special Topics in Supply Chain Management

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CERIAS Security: Attribute-Based Access Control 2/6

Clip 2/6 Speaker: William Winsborough · George Mason University Basing authorization on attributes of the resource requester provides flexibility and scalability that is essential in the context of large distributed systems. Logic programming provides an convenient, expressive, and we

From playlist The CERIAS Security Seminars 2004

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25c3: Privacy in the social semantic web

Speaker: Jan Torben Social networks based on XMPP Thank you all for your feedback. I currently register some hacking space on berlios.de so we can have a mailing list and maybe a wiki! please contact me at: jan.heuer uni-muenster.de In the last years the static web has moved towards an i

From playlist 25C3: Nothing to hide

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The Defence Context, Geospatial Standards for Data Science - Dr Paul Cripps, Dstl

About the event Advances in geospatial technologies have led to a significant increase in the role of geospatial data across sectors such as agriculture, aviation, energy, utilities, hydrology, smart cities, government, health and others. As more geospatial data has been collected and ana

From playlist Geospatial Standards for Data Science

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SOURCE Barcelona 2010: Security in Agile PLC - Practical navigational aid for speed boats

Speaker: Vishal Asthana, Symantec The conventional software development lifecycle is like a ship where development requirements once agreed upon have little scope for changes at later stages. Furthermore, just as ships typically have electronic navigational devices to help pilots avoid

From playlist SOURCE Barcelona 2010

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CERIAS Security: A Generalized Temporal Role Based Access Control Model 3/5

Clip 3/5 Speaker: James Joshi · Pittsburgh University A key issue in computer system security is to protect information against unauthorized access. Emerging workflow-based applications in healthcare, manufacturing, the financial sector, and e-commerce inherently have complex, time-ba

From playlist The CERIAS Security Seminars 2004

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Cryptography - Seminar 3 - Protocols

This seminar series is about the mathematical foundations of cryptography. In this seminar Eleanor McMurtry gives the formal definitions of machines, protocols, execution and UC-emulation in the context of universal composability, the foundations of cryptography that are being presented in

From playlist Metauni

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Network Security: Classical Encryption Techniques

Fundamental concepts of encryption techniques are discussed. Symmetric Cipher Model Substitution Techniques Transposition Techniques Product Ciphers Steganography

From playlist Network Security

Related pages

Probabilistic encryption | Symmetric-key algorithm | Plaintext | Ciphertext indistinguishability | Ciphertext | Provable security | Claude Shannon | Cryptosystem | ElGamal encryption | Randomness | Analysis of algorithms | Cryptography | PP (complexity)