Top PDF Cryptography and its application to operating system security

Cryptography and its application to operating system security

Cryptography and its application to operating system security

encryption (Katzan, 1977) (Diffie & Hellman, 1979). In contrast to substitution, transposition techniques actu[r]

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Protected Secret Sharing and its Application to Threshold Cryptography

Protected Secret Sharing and its Application to Threshold Cryptography

Consider an example where the director of a bank could generate shares for the bank’s vault and hand them out to his employees. Even if he is not available, the vault can be opened, but only, when a certain number of employees do it together. That certain number is called threshold. Threshold cryptography is the art of chopping a secret into little bits, so that the secret can only be learned by possessing more than a threshold number of those bits. In the context of cloud computing, threshold cryptography is described as a highly sensitive action like decryption or signing, which is performed by a group of cooperative servers in such a way that no minority of servers are able to perform the operations themselves, nor are they able to prevent the other servers from performing the operation when it is required. A good example of an application whose security could be greatly improved with a threshold solution is a network certification authority, a trusted entity that certifies that certifies that a given public key corresponds to a given user.
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Group Structure of Special Parabola and Its Application in Cryptography

Group Structure of Special Parabola and Its Application in Cryptography

Bin Li. Group Structure of Special Parabola and Its Application in Cryptography. Applied and Computational Mathematics. Vol. 8, No. 6, 2019, pp. 88-94. doi: 10.11648/j.acm.20190806.11 Received: November 5, 2019; Accepted: November 28, 2019; Published: December 9, 2019 Abstract: Public key cryptography is one of the most important research contents in modern cryptography. Curve-based public key cryptosystems have attracted widespread attention in recent years because they have more obvious advantages in speed and key length than general public key cryptosystems. People have done a lot of research on elliptic cryptosystem, among which the realization of elliptic cryptosystem is a key content. In this paper, the definition of special parabola in algebraic closed domain is proposed, the group structure of special parabola in finite field is studied, and several forms of public key cryptosystem based on this parabola are given. The results show that the parabola, together with the additive operations defined above, form an Abelian group. The radix of this parabola can be easily determined, so that the factors it contains can be large prime. The security of its public key cryptosystem is based on the difficulty of solving the discrete logarithm problem on this parabola. Moreover, these parabolic public key cryptosystems are easy to code and decode in plaintext, and easier to design and implement than elliptic curve public key cryptosystems.
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Multi-Instance  Security   and  its  Application  to  Password-Based  Cryptography

Multi-Instance Security and its Application to Password-Based Cryptography

We initiate the study of multi-instance security with a foundational treatment in two parts. The first part is agnostic to whether the setting is password-based or not, providing definitions for different kinds of mi-security of encryption and establishing relations between them, concluding with the message that what we call LORX-security is a good choice. The second part of our treatment focuses on password-based cryptography, providing a modular framework that proves mi-security of password-based primitives by viewing them as obtained by the composition of a mi-secure KDF with a si-secure primitive, and yielding in particular the first proof that salting works as expected to increase multi-instance security under a strong and formal metric for the latter.
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A Three Way Visual Cryptography & its Application in biometric Security : A Review

A Three Way Visual Cryptography & its Application in biometric Security : A Review

Keywords—Visual Cryptography, Encryption, Decryption, Shares, Extended Visual Cryptography I. INTRODUCTION Today, more and more digital documents are transmitted and exchanged on internet. It has created an environment that the digital information is easy to distribute, duplicate and modify. Image security becomes a very important issue for image transmission over the internet or wireless network. Visual Cryptography has made the security of information easier. Cryptography includes a set of techniques to achieve confidentiality when transmitting or storing data. Cryptography can be categorized into three different scheme s: symmetric cryptography, asymmetric cryptography and secret sharing. The traditional symmetric and asymmetric cryptography transform a given message to a random looking string of characters with the aid of a secret or public key. The resulting cipher text is supposed to reveal no information on plain text. The decryption of transforming the cipher text back to plain text is employed using the same or different secret key. In contrast to symmetric and asymmetric cryptography, secret sharing is based on the distribution of the secret information over several parties. Only if the required subset of parties put their information together the secret is revealed. The disadvantage of traditional symmetric and asymmetric cryptographic schemes is that they require complex operational steps for the encryption as well as for decryption of information. For average and inexperienced users, these schemes are rarely convenient to employ [2]. In 1994 Moni Naor and Adi Shamir [1] combined the two mechanisms : secret sharing and traditional cryptography. They introduced a new concept named Visual Cryptography for the encryption and decryption of printed materials such as images or text.
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Web Security based on the Application of Cryptography

Web Security based on the Application of Cryptography

The only practical approach for sending and storing information over network is to imply any kind of encryption. One of the major means of cyber attacks is the secret access to information sources and the organizations being completely unaware of the situation. To avoid this, ‘Quantum Cryptography’ is used. The major attribute of quantum cryptography is its ability to exchange the encryption key with absolute security. The history of cryptography dates back to the times of Julius Caesar. Julius used simple cryptographic techniques to encrypt his secret messages. The Caesar cipher is a monoalphabetic cryptosystem that replaces every given plain text letter by the same letter of the cipher text alphabet. However, the concepts such as source, receiver and channel codes are all modern advancements which have their roots in the information theory.
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On the Application of Identity-Based Cryptography in Grid Security

On the Application of Identity-Based Cryptography in Grid Security

7.2 Suggestions for Future Work manage public keys in a lightweight, natural and flexible manner. 7.2 Suggestions for Future Work At the time of writing, no implementation of an identity-based grid security archi- tecture has been carried out either by grid or IBC research communities. This is partly because the study of the application of IBC in grid security at the architec- tural level is still an ongoing research avenue. This study is essential to understand and answer various fundamental issues and questions in regards to the suitability of IBC in grid applications, for example, could an identity-based security architec- ture support the use of short-term keys in a better way than using the conventional RSA-based PKI? In the medium-term, however, the development of prototypes that implement our IKIG and DKIG proposals would seem to be a sensible and natural follow-on. Nevertheless, constructing prototypes may not be straightforward and could be time-consuming. This is so because it is believed that all the currently available tools and mechanisms used to construct grid systems do not yet have the capability of supporting IBC. As we have discussed in Sections 4.8.2 and 5.8, GSS- API, OpenSSL, various web services security standards, and other grid-related tools must be modified/extended to support the adoption of identity-based cryptographic schemes. If prototypes of IKIG and DKIG can be developed successfully, actual performance figures could be obtained by testing the prototypes. These would be very useful in further assessing the efficiency and suitability of our IKIG and DKIG proposals.
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A Discussion on Elliptic Curve Cryptography and its Application

A Discussion on Elliptic Curve Cryptography and its Application

When the ECC was first introduced in 1985, there was a lot of skepticism about its security. However, ECC has since come a long way. After nearly a decade of serious study and scrutiny, ECC has yielded highly efficient and secure. Presently, many product vendors have incorporated ECC in their products, and this number has only been on the rise. Uncertainty still exists among some proponents of traditional cryptographic systems, but they are starting to become more accepting of this promising new technology. RSA Security Inc., for example, has long voiced concern regarding the security of ECC since its introduction. In recent years, however, RSA Security has researched on efficient ECC algorithms, and even acquired a patent on a storage- efficient basis conversion algorithm. Moreover, it has also integrated ECC into some of its products, acknowledging the fact that ECC has begun to establish itself as both secure and efficient. The factor is the strong promotion of the use of ECC through a Canadian-based Certicom Corporation. Certicom is a company that specializes in information security solutions in a mobile computing environment through providing software and services to its clients. Over the years, Certicom has published numerous papers in support of ECC and has also implemented ECC in all of its commercial products. Its success prompted many other companies to look more closely at the benefits and security of ECC. Now, ECC is becoming the mainstream cryptographic scheme in all mobile and wireless devices. Below is a short survey of ECC applications seen on the market today. Results of the survey can be broadly divided into some categories:
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Asynchronous Secret Reconstruction and Its Application to the Threshold Cryptography

Asynchronous Secret Reconstruction and Its Application to the Threshold Cryptography

( ) t n , SS, participating users in a threshold crypto- graphic application can be either legitimate group mem- bers or attackers. All threshold cryptographic applica- tions only consider the situation when all participating users are legitimate group members. When there are more than t users participating and values of users are released asynchronously in a threshold application, an attacker can always release his computed values last. In such a way, after knowing t valid values of legitimate group members, the attacker can obtain the valid output of the cryptographic function and therefore, can success- fully impersonate to be a legitimate group member with- out being detected. We also propose a modified scheme to fix this security problem.
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Zot-Binary: A New Number System And Its Application On Number Theory Based Public-Key Cryptography

Zot-Binary: A New Number System And Its Application On Number Theory Based Public-Key Cryptography

1 CHAPTER ONE: INTRODUCTION 1.1 General Overview The steady acceleration of advances in computer science, over the past few decades have resulted an insatiable human appetite for greater data efficiency and convenience. Thus, cryptography has become a part of daily life as a branch of computer science that provides security over data. Secure communications, financial transactions, education, healthcare are just few examples of the many elements of modern society that are closely in interaction with cryptography. This tremendous development of information technology has brought up importance of information security more than ever [1, 2]. According to [1, 2], the main responsibilities of cryptography in the information security are about achieving the following goals: Confidentiality, Data integrity, Authentication and Non-repudiation. In order to achieve the above-mentioned goals, some cryptographic primitives have been designed which can be listed as follows and detailed out in Figure 1.1.
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Operating System Security

Operating System Security

Verification that an implementation correctly enforces a system’s security goals goes far beyond verifying the authorization mechanisms are implemented correctly.The system implementation must be verified to ensure that all system resource mechanisms (see Chapter 1) are not vulnerable to attack. As computing hardware is complex, assurance of correct use of hardware for implementing system resources is nontrivial. Consider the memory system. A hardware component called the Translation Lookaside Buffer (TLB) holds a cache of mappings from virtual memory pages to their physical memory counterparts. If an attacker can modify these mappings they may be able to compromise the secrecy and integrity of system and user application data. Depending on the system architecture, TLBs may be filled by hardware or software. For hardware-filled TLBs, the system implementation must ensure that the page table entries used to fill the TLB cannot be modified by attackers. For software-filled TLBs, the refill code and data used by the code must be isolated from any attacker behavior. Further, other attacks may be possible if an attacker can gain access to secret memory after it is released. For example, heap allocation mechanisms must be verified to ensure clearing of all secret memory (e.g., to prevent object reuse). Even across reboots, secret data may be leaked as BIOS systems are inconsistent about whether they clear memory on boot or not, and data remains in memory for sometime after shutdown. As a result of these and other possible attack vectors (e.g., covert channels, see Chapter 5), careful verification of system implementations is necessary to ensure reference monitor guarantees, but it is a complex task.
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Cryptography Based Security for Cloud Computing System

Cryptography Based Security for Cloud Computing System

Amazon S3 stores objects redundantly across multiple facility in an Amazon S3 region. This redundancy helps is repairing data if there is a data corruption issue. In addition Amazon S3 also uses versioning to preserve every version of every object stored in our Amazon S3 bucket. Versioning allows us to easily recover from unintended user actions and application failures [6].

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Linux Operating System Security

Linux Operating System Security

• Know how to work with penetration testing systems and how to reduce their threat. • Understand network security issues and how to control network access. • Learn about some of the intrusion detection systems available. • Understand how the use of cryptography can improve system security, including topics such as VPNs, SSL/TLS, and OpenSSH.

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Role of Cryptography & its Related Techniques in Cloud Computing Security

Role of Cryptography & its Related Techniques in Cloud Computing Security

Abstract: Cloud Computing is a fast-growing area and its security issues block the prevalence widely. The organizations are lethargic in accepting it due to these issues and challenges associated with it. Security is the most important concern in cloud computing including the data protection, network security, virtualization security, application integrity, and identity management. Data protection is one of the most important among these issues. The major reason is, organizations will transfer their data to remote machines if and only if the cloud service providers provide guaranteed data protection. Even though many techniques are proposed/recommended for security in cloud computing, however, there are still a lot of challenges in this area.
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Security Enhancement System Based on the Integration of Cryptography and Steganography

Security Enhancement System Based on the Integration of Cryptography and Steganography

Figure 11: Correlation Analysis for Three Different Block Sizes: 30x30 pixels, 20x20 pixels and 10x10 pixels 6. Conclusion This paper proposes a security enhancement system for image and text which are widely used over electronic communication. At cryptographic point of view, the combining usage of image transformation and encryption technique makes the attackers more difficult for decryption process. Moreover, it can be clearly seen that there are lower correlation and higher entropy value when the proposed transformation algorithm is applied as pre- encryption step according to the analytical results. On the other hand, at the steganography point of view, the attackers cannot be easily suspicious the existence of hidden information as the encrypted cover is used for hiding the secret message. Thus, it can achieve the security requirements such as confidentiality of hidden message. Therefore, the proposed system can be applied in many security awareness application areas. In this system, only two image file types such as jpeg and bmp can be used for image cover. As further extension, the proposed block-based transformation algorithm can be tested together with other cryptographic encryption algorithms.
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Android Operating System Security Issues

Android Operating System Security Issues

The newer variants of GinMaster were able to avoid detection by most anti-virus software in order to get into devices. Using polymorphic tecchniques, the program would obfuscate class names for infected objects and randomize package names and certificates for applications. Other functionality of this malware was to steal confidential information, gain more permissions on the device, and install applications without user approval [Yu13]. There are many other similar Trojan or other malicious applications and GinMaster is just a single example of this type of problem. Other general categories of Android malware are Rootkit, Trojan spy, Malicious downloader, Click fraudster, Data stealer, and Premium service abuser. Users should always double check an application's permissions and whether or not they are getting the application from a trusted source before downloading.
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CYBER SECURITY & CRYPTOGRAPHY

CYBER SECURITY & CRYPTOGRAPHY

CRYPTOGRAPHY ELECTIVE 3 1 0 4 Preamble: This course is designed to provide theoretical concepts used in cryptography and to introduce the students to various cryptographic algorithms and techniques used for implementing data security and protection. This course also discusses common web application security vulnerabilities.

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CRYPTOGRAPHY IN NETWORK SECURITY

CRYPTOGRAPHY IN NETWORK SECURITY

authenticate the server before data is exchanged by the higher-level application. The SSL protocol maintains the security and integrity of the transmission channel by using encryption, authentication and message authentication codes. The SSL Handshake Protocol consists of two phases: server authentication and an optional client authentication. In the first phase, the server, in response to a client's request, sends its certificate and its cipher preferences. The client then generates a master key, which it encrypts with the server's public key, and transmits the encrypted master key to the server. The server recovers the master key and authenticates itself to the client by returning a message authenticated with the master key. Subsequent data is encrypted and authenticated with keys derived from this master key. In the optional second phase, the server sends a challenge to the client. The client authenticates itself to the server by returning the client's digital signature on the challenge, as well as its public key certificate.
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Android Operating System and its Security Issues

Android Operating System and its Security Issues

Abstract Android is a Mobile and Tablet Operating System premised on the Linux kernel owned by Google. The ultimate innovative feature of Android Operating System is open source due to this anyone can publish their applications freely on the Android market. This openness introduces the broad number of developers which utilize this platform, but it comes with the hazard that user may download malicious software which is written by network hackers and harm to its privacy. This requires the study of the Security Mechanisms for Android and to make it easy and user-friendly to make the user aware of areas where he has to be cautious.
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Application Security Support in the Operating System Kernel

Application Security Support in the Operating System Kernel

maintaining flexibility as application actions can implicitly cause permissions to be acquired (and released). Applications (and hence their developers) interact with the authorization system in two ways (1) when they request any operation and (2) when they try to change the authoriza- tion state. The impact the authorization system has on (1) is minimal because requests by the application may be de- nied for a variety of reasons (including lack of authorization) and need to be resilient against them. In (2), the applica- tions (and the developer) need to be aware of the authoriza- tion system, and sometimes the exact authorization config- uration, to make these changes. In kernelSec, the applica- tion’s explicit interactions with the authorization system is reduced by incorporating mechanisms that change the per- manent authorization state into the authorization configura- tion. Thus the authorization state changes can be triggered implicitly by application operations, eliminating the need for the developer to explicitly code them in the program. In this paper, we describe how kernelSec supports applica- tion security, provides support for high level authorization properties such as dynamic separation of duty, dynamic in- formation flow, and group management. In particular, the kernelSec’s group mechanism provides some administrative controls at the operating system level. This is the first OS implementation that we are aware of which provides this combination of general purpose and dynamic facilities. The remainder of this paper is organized as follows. Sec- tion 2 highlights the key features in kernelSec while Sec- tion 3 describes the design in detail. Section 4 describes the expressiveness of the protections that can be constructed in kernelSec, using a series of examples. Section 5 describes the current state of the kernelSec implementation, includ- ing some performance numbers. Section 6 describes the overview of how kernelSec addresses the expressiveness vs. complexity tradeoffs discussed above. In Section 7 we de- scribe related work and finally in Section 8 we conclude.
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