This document provides an overview and introduction to a cryptography course. It discusses how cryptography has evolved from a historical focus on secret codes to a modern scientific field. The document outlines the course goals of understanding theoretical foundations and applying a "crypto mindset". It also discusses necessary administrative details like the textbook, assignments, exams, and contact information for the professor and TAs.
This document provides a 3-paragraph summary of a lecture on cryptography:
Block ciphers encrypt blocks of plaintext into ciphertext using symmetric encryption algorithms and cryptographic keys. The lecture discusses block cipher modes of operation like Electronic Codebook (ECB), Cipher Block Chaining (CBC), and Counter mode (CTR) that extend block ciphers to encrypt arbitrarily long messages. ECB encrypts each block independently while CBC and CTR introduce dependencies between blocks to provide semantic security and prevent patterns in the ciphertext from revealing the plaintext. The lecture also covers cryptographic primitives like the Data Encryption Standard (DES) and the Advanced Encryption Standard (AES) and analyzes their security and performance.
This document provides an overview of cryptography concepts including:
- Homework 1 is due on 1/18 and project 1 is due the next day
- It reviews classical ciphers, modern symmetric ciphers like DES, and basic cryptography terminology
- It describes the Feistel cipher structure used in DES, the DES algorithm details like key scheduling and rounds, and strengths and weaknesses of DES versus alternatives like AES and triple DES
Cryptography and network security Nit701Amit Pathak
Cryptography and network security descries the security parameter with the help of public and private key. Digital signature is one of the most important area which we apply in our daily life for transferring the data.
- Public key cryptography uses asymmetric encryption involving two keys - a public key to encrypt and a private key to decrypt. This allows secure communication without pre-sharing keys.
- RSA was the first practical public key cryptosystem, based on the difficulty of factoring large prime numbers. It allows encryption with a public key and decryption with a private key.
- Diffie-Hellman key exchange allows two parties to jointly establish a shared secret key over an insecure channel without any prior secrets. This key can then be used to encrypt subsequent communications.
Public key cryptography uses two keys - a public key that can encrypt messages but not decrypt them, and a private key that can decrypt messages but not encrypt them. The RSA algorithm is a commonly used public key cryptosystem. It works by having users generate a public/private key pair using large prime numbers, then messages can be encrypted with the public key and decrypted with the private key. The security of RSA relies on the difficulty of factoring large numbers.
This document discusses network security and cryptography. It covers topics such as security requirements including confidentiality, integrity, authentication, and non-repudiation. It also discusses approaches to implementing these security requirements including encryption for confidentiality and digital signatures for authentication and non-repudiation. Additionally, it covers network threats and attacks, classifications of cryptosystems including classical and modern cryptosystems, key management, public key cryptography, and internet security protocols like IPSec and SSL/TLS.
This document provides a 3-paragraph summary of a lecture on cryptography:
Block ciphers encrypt blocks of plaintext into ciphertext using symmetric encryption algorithms and cryptographic keys. The lecture discusses block cipher modes of operation like Electronic Codebook (ECB), Cipher Block Chaining (CBC), and Counter mode (CTR) that extend block ciphers to encrypt arbitrarily long messages. ECB encrypts each block independently while CBC and CTR introduce dependencies between blocks to provide semantic security and prevent patterns in the ciphertext from revealing the plaintext. The lecture also covers cryptographic primitives like the Data Encryption Standard (DES) and the Advanced Encryption Standard (AES) and analyzes their security and performance.
This document provides an overview of cryptography concepts including:
- Homework 1 is due on 1/18 and project 1 is due the next day
- It reviews classical ciphers, modern symmetric ciphers like DES, and basic cryptography terminology
- It describes the Feistel cipher structure used in DES, the DES algorithm details like key scheduling and rounds, and strengths and weaknesses of DES versus alternatives like AES and triple DES
Cryptography and network security Nit701Amit Pathak
Cryptography and network security descries the security parameter with the help of public and private key. Digital signature is one of the most important area which we apply in our daily life for transferring the data.
- Public key cryptography uses asymmetric encryption involving two keys - a public key to encrypt and a private key to decrypt. This allows secure communication without pre-sharing keys.
- RSA was the first practical public key cryptosystem, based on the difficulty of factoring large prime numbers. It allows encryption with a public key and decryption with a private key.
- Diffie-Hellman key exchange allows two parties to jointly establish a shared secret key over an insecure channel without any prior secrets. This key can then be used to encrypt subsequent communications.
Public key cryptography uses two keys - a public key that can encrypt messages but not decrypt them, and a private key that can decrypt messages but not encrypt them. The RSA algorithm is a commonly used public key cryptosystem. It works by having users generate a public/private key pair using large prime numbers, then messages can be encrypted with the public key and decrypted with the private key. The security of RSA relies on the difficulty of factoring large numbers.
This document discusses network security and cryptography. It covers topics such as security requirements including confidentiality, integrity, authentication, and non-repudiation. It also discusses approaches to implementing these security requirements including encryption for confidentiality and digital signatures for authentication and non-repudiation. Additionally, it covers network threats and attacks, classifications of cryptosystems including classical and modern cryptosystems, key management, public key cryptography, and internet security protocols like IPSec and SSL/TLS.
This presentation contains the basics of cryptography. I have developed this presentation as a course material of Cryptography during my honors final year examination
This document provides an overview of cryptography concepts including symmetric and asymmetric key algorithms, cryptographic hashes, and tools for cryptanalysis. It defines common terminology like plaintext, ciphertext, encryption, and decryption. Symmetric algorithms discussed include the Vernam cipher, A5/1, DES, AES, and RC4. Asymmetric algorithms covered are RSA and Diffie-Hellman key exchange. Cryptographic hashes like MD5 and SHA-1 are also summarized along with resources for cryptanalysis.
This document provides an overview of cryptography concepts including symmetric and asymmetric key algorithms, cryptographic hashes, and tools for cryptanalysis. It defines common terminology like plaintext, ciphertext, encryption, and decryption. Symmetric algorithms discussed include the Vernam cipher, A5/1, DES, AES, and RC4. Asymmetric algorithms covered are RSA and Diffie-Hellman key exchange. Cryptographic hashes like MD5 and SHA-1 are also summarized along with resources for cryptanalysis.
This document provides an overview of public key cryptography and the RSA algorithm. It discusses how public key cryptography solves issues with symmetric key distribution and digital signatures by using separate public and private keys. The RSA algorithm is then explained, including how key pairs are generated, how encryption and decryption work using modular exponentiation, and an example of computing keys and encrypting a message.
The document discusses differential cryptanalysis and brute force attacks on the Data Encryption Standard (DES). It describes how in 1998, the Electronic Frontier Foundation built a machine that could crack a 56-bit DES key in 56 hours by testing 90 billion keys per second. It also discusses how Distributed.net used a network of 100,000 computers to crack DES in 22 hours by testing 245 billion keys per second, illustrating that DES could be broken with moderate resources. The document then covers double and triple DES, which increase key length for greater security.
This presentation will discuss leveraging analytics and machine learning techniques like deep learning, long short term memory networks, and gradient boosted machines for security applications like threat assessment. The presenter will compare current machine learning technologies and discuss best practices for applying predictive modeling to security problems, including data acquisition, feature selection, and model validation. The talk is part of a security roundtable event and will be followed by a lab exercise on developing predictive models.
The document discusses research approaches in cryptography. It outlines objectives to analytically study existing cryptographic systems and algorithms, compare their time and space complexity, and simulate vulnerabilities to cryptanalytic attacks. Common network attacks like wiretapping and denial of service are described along with solutions like encryption, authentication, and integrity checking. The RSA and Caesar ciphers are explained along with their encryption/decryption steps. MATLAB was used to implement RSA and Caesar and compare their time complexity.
This document discusses cryptographic security. It defines informational and computational security, and explains how security is quantified in bits based on the difficulty of cracking a cipher. The document also covers achieving security through provable security via mathematical proofs or heuristic evidence from failed attacks. Additionally, it discusses generating keys randomly or from passwords, and protecting keys through wrapping or hardware tokens. Potential issues like incorrect security proofs, legacy support with short keys, and implementation flaws are also noted.
This document provides an overview of a lecture on computer and network security. It discusses an upcoming JCE tutorial and homework assignment. It also lists assigned readings and asks for comments. The rest of the document summarizes a high-level survey of cryptography, covering goals like confidentiality and integrity. It discusses private-key settings where parties share a secret key, and provides examples of simple encryption schemes like shift ciphers and their limitations. It emphasizes using standardized cryptographic algorithms.
Introduction to cryptography part2-finalTaymoor Nazmy
This document provides an overview of symmetric and public key cryptography systems. It discusses how symmetric key cryptography uses a shared private key for encryption and decryption, while public key cryptography uses separate public and private keys. Symmetric systems are simpler and faster but require secure key exchange, while public key systems avoid this problem by allowing public distribution of public keys. The document then covers specific symmetric and public key algorithms as well as how digital signatures and certificates work with public key encryption.
Public key cryptography uses two keys: a public key to encrypt messages and a private key to decrypt them. The RSA algorithm is based on the difficulty of factoring large prime numbers. It works by having users generate a public/private key pair and publishing their public key. To encrypt a message, the sender uses the recipient's public key. Only the recipient can decrypt with their private key. The security of RSA relies on the computational difficulty of factoring the modulus used to generate the keys.
Quantum cryptography by Girisha Shankar, Sr. Manager, CiscoVishnu Pendyala
Quantum computing is said to break the Internet by making the underlying encryption ineffective. This session, hosted by ICON@Cisco tells you how Quantum cryptography, which has the potential to protect the Internet, works.
This document discusses public key cryptography and the RSA algorithm. It begins by explaining the limitations of private key cryptography and how public key cryptography addresses issues like key distribution and digital signatures. It then describes how RSA works, using two keys - a public key for encryption and a private key for decryption. It explains the key generation process, how messages are encrypted and decrypted, and discusses the mathematical principles and security of the RSA algorithm.
For a college course -- CNIT 140: "Cryptography for Computer Networks" at City College San Francisco
Instructor: Sam Bowne
More info: https://samsclass.info/141/141_S19.shtml
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
This document provides an overview of cryptography and network security concepts. It discusses computer security, network security, and internet security. It then covers security attacks like passive attacks which obtain transmitted information and active attacks which modify data. Security services like authentication, access control, and data confidentiality are explained. Security mechanisms like encipherment, digital signatures, and traffic padding are also introduced. Symmetric ciphers like the Caesar cipher, monoalphabetic cipher, Playfair cipher, polyalphabetic ciphers, and the one-time pad are described. Block ciphers principles involving confusion and diffusion are covered. The Data Encryption Standard (DES) cipher is explained in detail regarding its history, structure using Feistel networks, key size,
This document discusses the importance of instrumentation for effective fuzzing. It notes that while fuzzing may seem simple, it actually requires significant effort, target code adaptation, and input corpus minimization. Instrumentation is key to determining code coverage, finding new paths, and prioritizing inputs that lead to crashes or new code coverage. The document provides examples of instrumentation techniques using binary rewriting and hardware features and discusses how to set up fuzzing when source code is available versus when it is not. It also outlines some current gaps in fuzzing techniques.
Cryptography involves encrypting data using algorithms and keys to protect confidentiality, integrity, and authenticity. The document discusses the history and evolution of cryptography from manual ciphers to modern computer-based methods. It provides an overview of symmetric and asymmetric encryption techniques, and describes the Data Encryption Standard (DES) and its replacement by the Advanced Encryption Standard (AES).
This document discusses the core principles of modern cryptography: formal definitions, clear assumptions, and proofs of security. It emphasizes the importance of having precise definitions of what security means for a given cryptographic scheme. This allows meaningful analysis of schemes and understanding of their security guarantees. The document then discusses the definition of a secure private-key encryption scheme and introduces the notion of perfect secrecy. It proves that the one-time pad encryption scheme satisfies the definition of perfect secrecy.
This presentation contains the basics of cryptography. I have developed this presentation as a course material of Cryptography during my honors final year examination
This document provides an overview of cryptography concepts including symmetric and asymmetric key algorithms, cryptographic hashes, and tools for cryptanalysis. It defines common terminology like plaintext, ciphertext, encryption, and decryption. Symmetric algorithms discussed include the Vernam cipher, A5/1, DES, AES, and RC4. Asymmetric algorithms covered are RSA and Diffie-Hellman key exchange. Cryptographic hashes like MD5 and SHA-1 are also summarized along with resources for cryptanalysis.
This document provides an overview of cryptography concepts including symmetric and asymmetric key algorithms, cryptographic hashes, and tools for cryptanalysis. It defines common terminology like plaintext, ciphertext, encryption, and decryption. Symmetric algorithms discussed include the Vernam cipher, A5/1, DES, AES, and RC4. Asymmetric algorithms covered are RSA and Diffie-Hellman key exchange. Cryptographic hashes like MD5 and SHA-1 are also summarized along with resources for cryptanalysis.
This document provides an overview of public key cryptography and the RSA algorithm. It discusses how public key cryptography solves issues with symmetric key distribution and digital signatures by using separate public and private keys. The RSA algorithm is then explained, including how key pairs are generated, how encryption and decryption work using modular exponentiation, and an example of computing keys and encrypting a message.
The document discusses differential cryptanalysis and brute force attacks on the Data Encryption Standard (DES). It describes how in 1998, the Electronic Frontier Foundation built a machine that could crack a 56-bit DES key in 56 hours by testing 90 billion keys per second. It also discusses how Distributed.net used a network of 100,000 computers to crack DES in 22 hours by testing 245 billion keys per second, illustrating that DES could be broken with moderate resources. The document then covers double and triple DES, which increase key length for greater security.
This presentation will discuss leveraging analytics and machine learning techniques like deep learning, long short term memory networks, and gradient boosted machines for security applications like threat assessment. The presenter will compare current machine learning technologies and discuss best practices for applying predictive modeling to security problems, including data acquisition, feature selection, and model validation. The talk is part of a security roundtable event and will be followed by a lab exercise on developing predictive models.
The document discusses research approaches in cryptography. It outlines objectives to analytically study existing cryptographic systems and algorithms, compare their time and space complexity, and simulate vulnerabilities to cryptanalytic attacks. Common network attacks like wiretapping and denial of service are described along with solutions like encryption, authentication, and integrity checking. The RSA and Caesar ciphers are explained along with their encryption/decryption steps. MATLAB was used to implement RSA and Caesar and compare their time complexity.
This document discusses cryptographic security. It defines informational and computational security, and explains how security is quantified in bits based on the difficulty of cracking a cipher. The document also covers achieving security through provable security via mathematical proofs or heuristic evidence from failed attacks. Additionally, it discusses generating keys randomly or from passwords, and protecting keys through wrapping or hardware tokens. Potential issues like incorrect security proofs, legacy support with short keys, and implementation flaws are also noted.
This document provides an overview of a lecture on computer and network security. It discusses an upcoming JCE tutorial and homework assignment. It also lists assigned readings and asks for comments. The rest of the document summarizes a high-level survey of cryptography, covering goals like confidentiality and integrity. It discusses private-key settings where parties share a secret key, and provides examples of simple encryption schemes like shift ciphers and their limitations. It emphasizes using standardized cryptographic algorithms.
Introduction to cryptography part2-finalTaymoor Nazmy
This document provides an overview of symmetric and public key cryptography systems. It discusses how symmetric key cryptography uses a shared private key for encryption and decryption, while public key cryptography uses separate public and private keys. Symmetric systems are simpler and faster but require secure key exchange, while public key systems avoid this problem by allowing public distribution of public keys. The document then covers specific symmetric and public key algorithms as well as how digital signatures and certificates work with public key encryption.
Public key cryptography uses two keys: a public key to encrypt messages and a private key to decrypt them. The RSA algorithm is based on the difficulty of factoring large prime numbers. It works by having users generate a public/private key pair and publishing their public key. To encrypt a message, the sender uses the recipient's public key. Only the recipient can decrypt with their private key. The security of RSA relies on the computational difficulty of factoring the modulus used to generate the keys.
Quantum cryptography by Girisha Shankar, Sr. Manager, CiscoVishnu Pendyala
Quantum computing is said to break the Internet by making the underlying encryption ineffective. This session, hosted by ICON@Cisco tells you how Quantum cryptography, which has the potential to protect the Internet, works.
This document discusses public key cryptography and the RSA algorithm. It begins by explaining the limitations of private key cryptography and how public key cryptography addresses issues like key distribution and digital signatures. It then describes how RSA works, using two keys - a public key for encryption and a private key for decryption. It explains the key generation process, how messages are encrypted and decrypted, and discusses the mathematical principles and security of the RSA algorithm.
For a college course -- CNIT 140: "Cryptography for Computer Networks" at City College San Francisco
Instructor: Sam Bowne
More info: https://samsclass.info/141/141_S19.shtml
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
This document provides an overview of cryptography and network security concepts. It discusses computer security, network security, and internet security. It then covers security attacks like passive attacks which obtain transmitted information and active attacks which modify data. Security services like authentication, access control, and data confidentiality are explained. Security mechanisms like encipherment, digital signatures, and traffic padding are also introduced. Symmetric ciphers like the Caesar cipher, monoalphabetic cipher, Playfair cipher, polyalphabetic ciphers, and the one-time pad are described. Block ciphers principles involving confusion and diffusion are covered. The Data Encryption Standard (DES) cipher is explained in detail regarding its history, structure using Feistel networks, key size,
This document discusses the importance of instrumentation for effective fuzzing. It notes that while fuzzing may seem simple, it actually requires significant effort, target code adaptation, and input corpus minimization. Instrumentation is key to determining code coverage, finding new paths, and prioritizing inputs that lead to crashes or new code coverage. The document provides examples of instrumentation techniques using binary rewriting and hardware features and discusses how to set up fuzzing when source code is available versus when it is not. It also outlines some current gaps in fuzzing techniques.
Cryptography involves encrypting data using algorithms and keys to protect confidentiality, integrity, and authenticity. The document discusses the history and evolution of cryptography from manual ciphers to modern computer-based methods. It provides an overview of symmetric and asymmetric encryption techniques, and describes the Data Encryption Standard (DES) and its replacement by the Advanced Encryption Standard (AES).
This document discusses the core principles of modern cryptography: formal definitions, clear assumptions, and proofs of security. It emphasizes the importance of having precise definitions of what security means for a given cryptographic scheme. This allows meaningful analysis of schemes and understanding of their security guarantees. The document then discusses the definition of a secure private-key encryption scheme and introduces the notion of perfect secrecy. It proves that the one-time pad encryption scheme satisfies the definition of perfect secrecy.
This document describes a byte-wise shift cipher and Vigenère cipher. It discusses attacks that can be used to decrypt ciphertexts encrypted with these ciphers without knowing the key. For the byte-wise shift cipher, it is noted that the key space is too small at 256 keys to be secure. For the Vigenère cipher, frequency analysis of letters in different positions of the ciphertext can be used to determine the key length and individual bytes of the key. The same techniques can be applied to a byte-wise variant of the Vigenère cipher by analyzing frequencies of bytes in different ciphertext streams.
This document proposes a new protocol called SNARKBLOCK for anonymous blocklisting using zero-knowledge proofs. SNARKBLOCK allows users to prove they are not on a blocklist without revealing their identity. It improves on prior work by having verification that is logarithmic in the size of the blocklist, rather than linear. It also allows for "federated anonymous blocklisting" where websites can combine blocklists from different sources and choose which identity providers they trust. The core technical contribution is a new type of zero-knowledge proof called HICIAP that can aggregate multiple proofs over a common hidden input into a single short proof. This addresses issues with unlinkability in repeated interactions that require recomputing proofs.
This document discusses methods for finding the period of a periodic function using discrete Fourier transforms (DFT). It presents two algorithms:
1. Algorithm I handles the special case where the period s divides the number of sample points N. It uses DFT to obtain frequencies that reveal the period.
2. Algorithm II handles the general case where s does not necessarily divide N. It uses continued fractions to approximate measured frequencies as rational numbers, whose denominators likely equal the period s.
The document also discusses applications to integer factorization by finding the period of functions over finite fields, and limitations of the classical approach that motivate the use of quantum computing.
The document discusses off-path attacks against public key infrastructures. It describes how an off-path attacker can leverage IP defragmentation cache poisoning to achieve DNS cache poisoning and exploit domain validation procedures to obtain fraudulent SSL certificates. This undermines the security of the web PKI by allowing attackers to spoof domains without direct access to traffic. The document also analyzes the impact on victims and potential mitigation techniques, concluding that domain validation needs to be strengthened to be resilient against man-in-the-middle attacks.
The document discusses discrepancies in how different software parse the Portable Executable (PE) file format used in Windows programs. It presents a systematic approach to model the constraints imposed by PE parsers in different software. This involves (1) modeling the parsing operations, (2) generating valid and differential test cases to explore differences, and (3) finding real malware exploiting discrepancies. The analysis found differences between Windows versions and other parsers that could allow malware evasion. Developing clearer specifications and modeling multiple parsers is important for security tools.
The document discusses new security risks emerging from the exposure function in 4G and 5G mobile networks. It summarizes that the exposure function creates a new front door for attacks by providing access to network APIs. The document outlines how attackers could potentially access these APIs by forging business credentials with mobile operators or IoT platforms. It then analyzes security issues found across nine commercial IoT platforms, finding vulnerabilities in API configuration, authentication, and access control that could allow attackers to obtain sensitive user data or compromise devices. Responsible disclosure of these issues is recommended to improve the security of network exposure functions.
Phenomics assisted breeding in crop improvementIshaGoswami9
As the population is increasing and will reach about 9 billion upto 2050. Also due to climate change, it is difficult to meet the food requirement of such a large population. Facing the challenges presented by resource shortages, climate
change, and increasing global population, crop yield and quality need to be improved in a sustainable way over the coming decades. Genetic improvement by breeding is the best way to increase crop productivity. With the rapid progression of functional
genomics, an increasing number of crop genomes have been sequenced and dozens of genes influencing key agronomic traits have been identified. However, current genome sequence information has not been adequately exploited for understanding
the complex characteristics of multiple gene, owing to a lack of crop phenotypic data. Efficient, automatic, and accurate technologies and platforms that can capture phenotypic data that can
be linked to genomics information for crop improvement at all growth stages have become as important as genotyping. Thus,
high-throughput phenotyping has become the major bottleneck restricting crop breeding. Plant phenomics has been defined as the high-throughput, accurate acquisition and analysis of multi-dimensional phenotypes
during crop growing stages at the organism level, including the cell, tissue, organ, individual plant, plot, and field levels. With the rapid development of novel sensors, imaging technology,
and analysis methods, numerous infrastructure platforms have been developed for phenotyping.
Remote Sensing and Computational, Evolutionary, Supercomputing, and Intellige...University of Maribor
Slides from talk:
Aleš Zamuda: Remote Sensing and Computational, Evolutionary, Supercomputing, and Intelligent Systems.
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Inter-Society Networking Panel GRSS/MTT-S/CIS Panel Session: Promoting Connection and Cooperation
https://www.etran.rs/2024/en/home-english/
Authoring a personal GPT for your research and practice: How we created the Q...Leonel Morgado
Thematic analysis in qualitative research is a time-consuming and systematic task, typically done using teams. Team members must ground their activities on common understandings of the major concepts underlying the thematic analysis, and define criteria for its development. However, conceptual misunderstandings, equivocations, and lack of adherence to criteria are challenges to the quality and speed of this process. Given the distributed and uncertain nature of this process, we wondered if the tasks in thematic analysis could be supported by readily available artificial intelligence chatbots. Our early efforts point to potential benefits: not just saving time in the coding process but better adherence to criteria and grounding, by increasing triangulation between humans and artificial intelligence. This tutorial will provide a description and demonstration of the process we followed, as two academic researchers, to develop a custom ChatGPT to assist with qualitative coding in the thematic data analysis process of immersive learning accounts in a survey of the academic literature: QUAL-E Immersive Learning Thematic Analysis Helper. In the hands-on time, participants will try out QUAL-E and develop their ideas for their own qualitative coding ChatGPT. Participants that have the paid ChatGPT Plus subscription can create a draft of their assistants. The organizers will provide course materials and slide deck that participants will be able to utilize to continue development of their custom GPT. The paid subscription to ChatGPT Plus is not required to participate in this workshop, just for trying out personal GPTs during it.
Describing and Interpreting an Immersive Learning Case with the Immersion Cub...Leonel Morgado
Current descriptions of immersive learning cases are often difficult or impossible to compare. This is due to a myriad of different options on what details to include, which aspects are relevant, and on the descriptive approaches employed. Also, these aspects often combine very specific details with more general guidelines or indicate intents and rationales without clarifying their implementation. In this paper we provide a method to describe immersive learning cases that is structured to enable comparisons, yet flexible enough to allow researchers and practitioners to decide which aspects to include. This method leverages a taxonomy that classifies educational aspects at three levels (uses, practices, and strategies) and then utilizes two frameworks, the Immersive Learning Brain and the Immersion Cube, to enable a structured description and interpretation of immersive learning cases. The method is then demonstrated on a published immersive learning case on training for wind turbine maintenance using virtual reality. Applying the method results in a structured artifact, the Immersive Learning Case Sheet, that tags the case with its proximal uses, practices, and strategies, and refines the free text case description to ensure that matching details are included. This contribution is thus a case description method in support of future comparative research of immersive learning cases. We then discuss how the resulting description and interpretation can be leveraged to change immersion learning cases, by enriching them (considering low-effort changes or additions) or innovating (exploring more challenging avenues of transformation). The method holds significant promise to support better-grounded research in immersive learning.
Current Ms word generated power point presentation covers major details about the micronuclei test. It's significance and assays to conduct it. It is used to detect the micronuclei formation inside the cells of nearly every multicellular organism. It's formation takes place during chromosomal sepration at metaphase.
Unlocking the mysteries of reproduction: Exploring fecundity and gonadosomati...AbdullaAlAsif1
The pygmy halfbeak Dermogenys colletei, is known for its viviparous nature, this presents an intriguing case of relatively low fecundity, raising questions about potential compensatory reproductive strategies employed by this species. Our study delves into the examination of fecundity and the Gonadosomatic Index (GSI) in the Pygmy Halfbeak, D. colletei (Meisner, 2001), an intriguing viviparous fish indigenous to Sarawak, Borneo. We hypothesize that the Pygmy halfbeak, D. colletei, may exhibit unique reproductive adaptations to offset its low fecundity, thus enhancing its survival and fitness. To address this, we conducted a comprehensive study utilizing 28 mature female specimens of D. colletei, carefully measuring fecundity and GSI to shed light on the reproductive adaptations of this species. Our findings reveal that D. colletei indeed exhibits low fecundity, with a mean of 16.76 ± 2.01, and a mean GSI of 12.83 ± 1.27, providing crucial insights into the reproductive mechanisms at play in this species. These results underscore the existence of unique reproductive strategies in D. colletei, enabling its adaptation and persistence in Borneo's diverse aquatic ecosystems, and call for further ecological research to elucidate these mechanisms. This study lends to a better understanding of viviparous fish in Borneo and contributes to the broader field of aquatic ecology, enhancing our knowledge of species adaptations to unique ecological challenges.
hematic appreciation test is a psychological assessment tool used to measure an individual's appreciation and understanding of specific themes or topics. This test helps to evaluate an individual's ability to connect different ideas and concepts within a given theme, as well as their overall comprehension and interpretation skills. The results of the test can provide valuable insights into an individual's cognitive abilities, creativity, and critical thinking skills
2. Welcome!
• Crypto is amazing!
– Can do things that seem impossible…
• Crypto is important and pervasive
– It impacts each of us every day
• Crypto is fun!
– Deep theory interacting with practice
– Attackers’ mindset, fun assignments
3. This is a tough class
• Mathematical prerequisites
– Discrete math, probability, modular arithmetic
– Mathematical maturity
• Definitions, theorems, proofs, abstraction
• CS prerequisites
– Pseudocode/algorithms, big-O notation
– Programming assignments
• Hard part should not be the programming, but the
thought behind it
• Some flexibility in language, but need to read code I
provide
4. Tips for doing well
• Read relevant sections of book
before class
– Lecture will move quickly; I expect
questions and discussion
– If you fall behind on the reading it will
be hard to catch up!
– Can also watch my videos on Coursera
• Attend class
• Come to office hours
5. Necessary administrative
stuff
• Course webpage:
http://www.cs.umd.edu/~jkatz/crypto/s22
– General information posted there
– Syllabus/schedule/readings posted there
• Midterm already scheduled
• Updated as semester progresses
– Slides posted there after lecture, but I will
use the whiteboard in class
6. Necessary administrative
stuff
• ELMS/Canvas
– HWs will be posted on ELMS
– Professor/TA Zoom links posted there
– Lectures will not be recorded
• Piazza
– Announcements will be sent there
– Useful for discussions/questions
– Please use also for questions about the
content, not just about the homeworks!
7. Lectures
• In-person lectures (unless campus
policy changes)
• Lectures will not be recorded
• I advise you to attend in person
unless you are sick
8. Homeworks
• HWs submitted using Gradescope
– Make sure you are registered, and can submit,
well in advance of the first deadline
• When applicable:
– Type solutions using LaTeX (preferred)
– Clear scan of neat handwritten solutions
– Word doc converted to pdf
– .txt files
• Cheating will not be tolerated
– Must write your own code/solutions
– No consulting external websites
9. HWs/exams
• Expect HWs every 1.5-2 weeks
– Ungraded/optional HWs focusing on the theory
• Solutions given
– Graded HWs involving programming
• Meant to reinforce the abstract concepts
• Meant to highlight practical applications
• Fun!
• Midterm and final
– Questions more similar to ungraded HWs
– Anything covered in class or listed in readings
on syllabus is fair game
10. Textbook
• Required textbook: “Introduction to
Modern Cryptography, 3rd
edition,”
Katz and Lindell
• Exams will be open book
– Physical copies only; no electronic
devices
11. Grading
• Grading based on 7-8 HWs (25%),
midterm (35%), and final (40%)
– Exams count a lot
• Class is not curved
– Each student’s grade determined by how well
they demonstrate their understanding of the
material
– Every student is capable of getting an A
– You are not competing with each other
A: 86-100
B: 70-85
C: 55-69
D/F: below
55
12. TAs
• Doruk Gur
• Guanhong Wang
• Office hours listed on webpage
– May change as semester progresses
13. How to reach me
• Best way to contact me is by email:
jkatz@cs.umd.edu
• Please put “CMSC 456” in subject
line
• Please email me in advance if you
plan to come to office hours
15. Course goals
• Understand the theoretical foundations
for real-world cryptography
• When you encounter crypto in your
career:
– Understand the key terms
– Understand the security guarantees
needed/provided
– Know how to use crypto
– Understand what goes on “under the hood”
• “Crypto mindset”
16. Course non-goals
• Designing your own crypto schemes
– This is hard!
• Implementing crypto for real-world
use
– This is hard!
•Course goal:
realize when to consult an expert!
17. Cryptography (historically)
“…the art of writing or solving
codes…”
• Historically, cryptography focused
exclusively on ensuring private
communication
between two parties sharing secret
information in advance using “codes”
(aka
private-key encryption)
18. Modern cryptography
• Much broader scope!
– Data integrity, authentication, protocols, …
– The public-key setting
– Group communication
– More-complicated trust models
– Foundations (e.g., number theory,
quantum-resistance) to systems (e.g.,
electronic voting, privacy-preserving ML,
blockchain, DeFi)
19. Modern cryptography
Design, analysis, and implementation of
mathematical techniques for securing
information, systems, and distributed
computations against adversarial attack
20. Cryptography (historically)
“…the art of writing or solving
codes…”
• Historically, cryptography was an art
– Heuristic, unprincipled design and
analysis
– Schemes proposed, broken, repeat…
21. Modern cryptography
• Cryptography is now much more of a
science
– Rigorous analysis, firm foundations,
deeper understanding, rich theory
• The “crypto mindset” has permeated
other areas of computer security
– Threat modeling
– Proofs of security
22. Cryptography (historically)
• Used primarily for
military/government applications,
plus a few niche applications in
industry (e.g., banking)
23. Modern cryptography
• Cryptography is ubiquitous!
– Password-based authentication, password
hashing
– Secure credit-card transactions over the
internet
– Encrypted WiFi
– Disk encryption
– Digitally signed software updates
– Bitcoin
– …
24. Rough course outline
• Building blocks
– Pseudorandom (number) generators
– Pseudorandom functions/block ciphers
– Hash functions
– Number theory
Secrecy Integrity
Private-key
setting
Private-key
encryption
Message
authentication
codes
Public-key
setting
Public-key
encryption
Digital signatures
26. Motivation
• Allows us to “ease into things…,”
introduce notation
• Illustrates why things are more
difficult than they may appear
• Motivates a more rigorous approach
27. Classical cryptography
• Until the 1970s, exclusively
concerned with ensuring secrecy of
communication
• I.e., encryption
28. Classical cryptography
• Until the 1970s, relied exclusively on
secret information (a key) shared in
advance between the communicating
parties
Private-key cryptography
– aka secret-key / shared-key / symmetric-
key cryptography
31. Private-key encryption
• A private-key encryption scheme is defined
by a message space M and algorithms (Gen,
Enc, Dec):
– Gen (key-generation algorithm): outputs kK
– Enc (encryption algorithm): takes key k and
message
mM as input; outputs ciphertext c
c Enck(m)
– Dec (decryption algorithm): takes key k and
ciphertext c as input; outputs m or “error”
m := Deck(c)
For all mM and k output by
Gen,
Deck(Enck(m)) = m
32. Kerckhoffs’s principle
• The encryption scheme is not secret
– The attacker knows the encryption scheme
– The only secret is the key
– The key must be chosen at random; kept secret
• Arguments in favor of this principle
– Easier to keep key secret than algorithm
– Easier to change key than to change algorithm
– Standardization
• Ease of deployment
• Public scrutiny
33. The shift cipher
• Consider encrypting English text
• Associate ‘a’ with 0; ‘b’ with 1; …; ‘z’
with 25
• k K = {0, …, 25}
• To encrypt using key k, shift every letter
of the plaintext by k positions (with
wraparound)
• Decryption just does the reverse
helloworldz
ccccccccccc
jgnnqyqtnfb
34. Modular arithmetic
• x = y mod N if and only if N divides x-y
• [x mod N] = the remainder when x is divided by
N
– I.e., the unique value y{0, …, N-1} such that
x = y mod N
• 25 = 35 mod 10
• 25 ≠ [35 mod 10]
• 5 = [35 mod 10]
35. The shift cipher, formally
• M = {strings over lowercase English
alphabet}
• Gen: choose uniform k{0, …, 25}
• Enck(m1…mt): output c1…ct, where
ci := [mi + k mod 26]
• Deck(c1…ct): output m1…mt, where
mi := [ci - k mod 26]
• Can verify that correctness holds…
36. Is the shift cipher secure?
• No -- only 26 possible keys!
– Given a ciphertext, try decrypting with
every possible key
– Only one possibility will “make sense”
– (What assumptions are we making here?)
• Example of a “brute-force” or
“exhaustive-search” attack
38. Byte-wise shift cipher
• Work with an alphabet of bytes
rather than (English, lowercase)
letters
– Works natively for arbitrary data!
• Use XOR instead of modular addition
– Essential properties still hold
39. Hexadecimal (base 16)
He
x
Bits
(“nibble
”)
Decim
al
0 0000 0
1 0001 1
2 0010 2
3 0011 3
4 0100 4
5 0101 5
6 0110 6
7 0111 7
He
x
Bits
(“nibble
”)
Deci
mal
8 1000 8
9 1001 9
A 1010 10
B 1011 11
C 1100 12
D 1101 13
E 1110 14
F 1111 15
43. Useful observations
• Only 128 valid ASCII chars (128 bytes
invalid)
• Only 0x20-0x7E printable
• 0x41-0x7a includes all
upper/lowercase letters
– Uppercase letters begin with 0x4 or 0x5
– Lowercase letters begin with 0x6 or 0x7