• Title/Summary/Keyword: symmetric encryption

Search Result 168, Processing Time 0.021 seconds

A Study on the Design of a Secure Client-Sever System (Secure 클라이언트-서버 시스템 설계에 관한 연구)

  • 이상렬
    • Journal of the Korea Society of Computer and Information
    • /
    • v.3 no.4
    • /
    • pp.91-96
    • /
    • 1998
  • In this paper we designed a secure client-server system to be able to protect messages between client and server using cryptography We authenticated each other using a asymmetric encryption algorithm on the logon procedure and minimized the time to encrypt and decrypt messages using a symmetric encryption algorithm on exchanging messages. We proved that it is possible to make a digital signature on our secure client-server system. And we suggested the efficient key management method to generate and distribute cryptograpic key securely.

  • PDF

TF-CPABE: An efficient and secure data communication with policy updating in wireless body area networks

  • Chandrasekaran, Balaji;Balakrishnan, Ramadoss;Nogami, Yasuyuki
    • ETRI Journal
    • /
    • v.41 no.4
    • /
    • pp.465-472
    • /
    • 2019
  • The major challenge in wireless body area networks (WBAN) is setting up a protected communication between data consumers and a body area network controller while meeting the security and privacy requirements. This paper proposes efficient and secure data communication in WBANs using a Twofish symmetric algorithm and ciphertext-policy attribute-based encryption with constant size ciphertext; in addition, the proposed scheme incorporates policy updating to update access policies. To the best of the author's knowledge, policy updating in WBAN has not been studied in earlier works. The proposed scheme is evaluated in terms of message size, energy consumption, and computation cost, and the results are compared with those of existing schemes. The result shows that the proposed method can achieve higher efficiency than conventional methods.

ID-based signcryption with improved security (안전성을 보완한 ID기반 signcryption 기법)

  • Kwak Byeong-Ok;Jeong Yoon-Su;Lee Sang-Ho
    • Journal of the Korea Society of Computer and Information
    • /
    • v.11 no.2 s.40
    • /
    • pp.239-251
    • /
    • 2006
  • Zheng's signcryption scheme is a new encryptical scheme of which can save more expense than those of the current signature encryption by using digital signature and symmetric key encryption logically. The current signcryption schemes have a problem that is to be exposed the secret key of the receiver in the case of checking repudiation of origin by the third party. To solve this problem, a solution suggested in this paper is to use multi-purpose ID-based signcryption scheme with anonymity and unlinkability. This solution is safe and more efficient than current signcryption schemes because the suggested scheme keeps the security of the random oracle model as using Weil-pairing in encryption. and follows a formal proof of semantic security of the decisional Diffie-Hellman problem.

  • PDF

Efficient Key Management Protocol for Secure RTMP Video Streaming toward Trusted Quantum Network

  • Pattaranantakul, Montida;Sanguannam, Kittichai;Sangwongngam, Paramin;Vorakulpipat, Chalee
    • ETRI Journal
    • /
    • v.37 no.4
    • /
    • pp.696-706
    • /
    • 2015
  • This paper presents an achievable secure videoconferencing system based on quantum key encryption in which key management can be directly applied and embedded in a server/client videoconferencing model using, for example, OpenMeeting. A secure key management methodology is proposed to ensure both a trusted quantum network and a secure videoconferencing system. The proposed methodology presents architecture on how to share secret keys between key management servers and distant parties in a secure domain without transmitting any secrets over insecure channels. The advantages of the proposed secure key management methodology overcome the limitations of quantum point-to-point key sharing by simultaneously distributing keys to multiple users; thus, it makes quantum cryptography a more practical and secure solution. The time required for the encryption and decryption may cause a few seconds delay in video transmission, but this proposed method protects against adversary attacks.

Accelerated VPN Encryption using AES-NI (AES-NI를 이용한 VPN 암호화 가속화)

  • Jeong, Jin-Pyo;Hwang, Jun-Ho;Han, Keun-Hee;Kim, Seok-Woo
    • Journal of the Korea Institute of Information Security & Cryptology
    • /
    • v.24 no.6
    • /
    • pp.1065-1078
    • /
    • 2014
  • Considering the safety of the data and performance, it can be said that the performance of the AES algorithm in a symmetric key-based encryption is the best in the IPSec-based VPN. When using the AES algorithm in IPSec-based VPN even with the expensive hardware encryption card such as OCTEON Card series of Cavium Networks, the Performance of VPN works less than half of the firewall using the same hardware. In 2008, Intel announced a set of 7 AES-NI instructions in order to improve the performance of the AES algorithm on the Intel CPU. In this paper, we verify how much the performance IPSec-based VPN can be improved when using seven sets of AES-NI instruction of the Intel CPU.

The Hardware Design of Integrated Security Core for IoT Devices (사물인터넷 기기를 위한 통합 보안 코어의 하드웨어 설계)

  • Gookyi, Dennis A.N.;Ryoo, Kwangki
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2017.10a
    • /
    • pp.584-586
    • /
    • 2017
  • In this paper we provide a unified crypto core that integrates lightweight symmetric cryptography and authentication. The crypto core implements a unified 128 bit key architecture of PRESENT encryption algorithm and a new lightweight encryption algorithm. The crypto core also consist of an authentication unit which neglects the use of hashing algorithms. Four algorithms are used for authentication which come from the Hopper-Blum (HB) and Hopper-Blum-Munilla-Penado (HB-MP) family of lightweight authentication algorithms: HB, HB+, HB-MP and HB-MP+. A unified architecture of these algorithms is implemented in this paper. The unified cryptosystem is designed using Verilog HDL, simulated with Modelsim SE and synthesized with Xilinx Design Suite 14.3. The crypto core synthesized to 1130 slices at 189Mhz frequency on Spartan6 FPGA device.

  • PDF

Signcryption Schemes with Forward Secrecy (Forward Secrecy를 제공하는 Signcryption 기법들)

  • 정희윤;이동훈;임종인
    • Journal of the Korea Institute of Information Security & Cryptology
    • /
    • v.11 no.5
    • /
    • pp.43-52
    • /
    • 2001
  • Y. Zheng introduced a new type of cryptograghic primitive as \"signcryption\", which combines a function of digital signature scheme with a symmetric key encryption algorithm. Signcryption doesn\`t only provide authenticity and confidentiality in a single step, but also give more efficient computation than the traditional \"signature-then-encryption\". And C. Gamage proposed a proxy-signcryption that efficiently combines a proxy signature with the signcryption. But, in the proposed signcryption schemes, one who obtains the sender\`s private key can recover the original message of a signcrypted text. That is, forward secrecy is not offered by the signcryption scheme with respect to the sender\`s private key. In this paper, we will propose a modified signcryption of Zheng\`s signcryption and a variant of proxy-signcryption with forward secrecy.ith forward secrecy.

BACS : An Experimental Study For Access Control System In Public Blockchain (BACS : 퍼블릭 블록체인 접근 통제 시스템에 관한 실험적 연구)

  • Han, Sejin;Lee, Sunjae;Lee, Dohyeon;Park, Sooyoung
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.20 no.1
    • /
    • pp.55-60
    • /
    • 2020
  • In this paper, we propose an access control system using cryptography as a method to protect personal data in public blockchain. The proposed system is designed to encrypt data according to the access policy, store it in the blockchain, and decrypt only the person who satisfy the access policy. In order to improve performance and scalability, an encryption mechanism is implemented outside the blockchain. Therefore, data access performance could be preserved while cryptographic operations executed Furthermore it can also improve the scalability by adding new access control modules while preserving the current configuration of blockchain network. The encryption scheme is based on the attribute-based encryption (ABE). However, unlike the traditional ABE, the "retention period", is incorporated into the access structure to ensure the right to be forgotten. In addition, symmetric key cryptograpic algorithms are used for the performance of ABE. We implemented the proposed system in a public blockchain and conducted the performance evaluation.

Cryptft+ : Python/Pyqt based File Encryption & Decryption System Using AES and HASH Algorithm (Crypft+ : Python/PyQt 기반 AES와 HASH 알고리즘을 이용한 파일 암복호화 시스템)

  • Shin, Dongho;Bae, Woori;Shin, Hyeonggyu;Nam, Seungjin;Lee, Hyung-Woo
    • Journal of Internet of Things and Convergence
    • /
    • v.2 no.3
    • /
    • pp.43-51
    • /
    • 2016
  • In this paper, we have developed Crypft+ as an enhanced file encryption/decryption system to improve the security of IoT system or individual document file management process. The Crypft+ system was developed as a core security module using Python, and designed and implemented a user interface using PyQt. We also implemented encryption and decryption function of important files stored in the computer system using AES based symmetric key encryption algorithm and SHA-512 based hash algorithm. In addition, Cx-Freezes module is used to convert the program as an exe-based executable code. Additionally, the manual for understanding the Cryptft+ SW is included in the internal program so that it can be downloaded directly.

A Study on Encryption Method using Hash Chain and Session Key Exchange in DRM System (DRM 시스템에서 해쉬체인과 세션키 교환을 이용한 암호화 기법에 관한 연구)

  • Park, Chan-Kil;Kim, Jung-Jae;Lee, Kyung-Seok;Jun, Moon-Seog
    • The KIPS Transactions:PartC
    • /
    • v.13C no.7 s.110
    • /
    • pp.843-850
    • /
    • 2006
  • This is devoted to first, to propose a hash chain algorithm that generates more secure key than conventional encryption method. Secondly, we proposes encryption method that is more secure than conventional system using a encryption method that encrypts each block with each key generated by a hash chain algorithm. Thirdly, After identifying the user via wired and wireless network using a user authentication method. We propose a divided session key method so that Although a client key is disclosed, Attackers cannot catch a complete key and method to safely transfer the key using a divided key method. We make an experiment using various size of digital contents files for performance analysis after performing the design and implementation of system. Proposed system can distribute key securely than conventional system and encrypt data to prevent attacker from decrypting complete data although key may be disclosed. The encryption and decryption time that client system takes to replay video data fie is analogous to the conventional method.