• Journal of information and communication convergence engineering
• /
• v.12 no.3
• /
• pp.145-153
• /
• 2014

The improvements of embedded processors make future technologies including wireless sensor network and internet of things feasible. These applications firstly gather information from target field through wireless network. However, this networking process is highly vulnerable to malicious attacks including eavesdropping and forgery. In order to ensure secure and robust networking, information should be kept in secret with cryptography. Well known approach is public key cryptography and this algorithm consists of finite field arithmetic. There are many works considering high speed finite field arithmetic. One of the famous approach is Montgomery multiplication. In this study, we investigated Montgomery multiplication for public key cryptography on embedded microprocessors. This paper includes helpful information on Montgomery multiplication implementation methods and techniques for various target devices including 8-bit and 16-bit microprocessors. Further, we expect that the results reported in this paper will become part of a reference book for advanced Montgomery multiplication methods for future researchers.

• Journal of Communications and Networks
• /
• v.10 no.1
• /
• pp.10-17
• /
• 2008

In traditional digital signature schemes, certificates signed by a trusted party are required to ensure the authenticity of the public key. In Asiacrypt 2003, the concept of certificateless signature scheme was introduced. The advantage of certificateless public key cryptography successfully eliminates the necessity of certificates in the traditional public key cryptography and simultaneously solves the inherent key escrow problem suffered in identity-based cryptography. Recently, Yap et al. proposed an efficient certificateless signature scheme and claimed that their scheme is existentially unforgeable in the random oracle model. In this paper, we show that the certificateless signature scheme proposed by Yap et al. is insecure against public key replacement attacks. Furthermore, we propose an improved certificateless signature scheme, which is existentially unforgeable against adaptive chosen message attacks under the computational Diffie-Hellman assumption in the random oracle model and provide the security proof of the proposed scheme.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.4 no.2
• /
• pp.98-116
• /
• 2010

The field of lightweight cryptography has developed significantly over recent years and many impressive implementation results have been published. However these results are often concerned with a core computation and when it comes to a real implementation there can be significant hidden overheads. In this paper we consider the case of cryptoGPS and we outline a full implementation that has been fabricated in ASIC. Interestingly, the implementation requirements still remain within the typically-cited limits for on-the-tag cryptography.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.17 no.8
• /
• pp.1857-1864
• /
• 2013

In this paper, we improve the quantum cryptography system using a dual photon transmission plaintext user password algorithmwas designed to implementthe exchange. Existing quantum cryptographic key transport protocols, algorithms, mainly as a quantum cryptography system using the paper, but it improved the way the dual photon transmission through the quantum algorithm re not getting transmitted plaintext.

• Journal of information and communication convergence engineering
• /
• v.2 no.3
• /
• pp.182-186
• /
• 2004

When most of existing instant messengers log on server, they transmit to sever in encoding password to RC5. but RC5 don't be secured because it has been known many of password cracking tools. Also, messengers don't have any protection on the transmitted information with communicating two hosts since loging on, endangering the privacy of the user. As a counter measure, messengers need to provide security service including message encryption. In this paper, we designed a key exchange method of password representing fast, effective and high security degree, using ECC(Elliptic Curve Cryptography) that being known the very stronger than another public key cryptography with same key size. To effectively improve data transmission and its security using IPSec protocol between users, tunnel mode is introduced. Tunnel mode transmits Host-to-Host data through virtual pipelines on the Internet.

• Journal of information and communication convergence engineering
• /
• v.11 no.1
• /
• pp.12-16
• /
• 2013

Sensor network is one of the strongest technologies for various applications including home automation, surveillance system and monitoring system. To ensure secure and robust network communication between sensor nodes, plain-text should be encrypted using encryption methods. However due to their limited computation power and storage, it is difficult to implement public key cryptography, including elliptic curve cryptography, RSA and pairing cryptography, on sensor networks. However, recent works have shown the possibility that public key cryptography could be made available in a sensor network environment by introducing the efficient multi-precision multiplication method. The previous method suggested a broad rule of multiplication to enhance performance. However, various features of sensor motes have not been considered. For optimized implementation, unique features should be handled. In this paper, we propose a fully optimized multiplication method depending on a different specification for sensor motes. The method improves performance by using more efficient instructions and general purpose registers.

• Journal of Korea Society of Industrial Information Systems
• /
• v.13 no.1
• /
• pp.68-75
• /
• 2008

Because ad hoc network is vulnerable to attacks such as routing disruption and resource consumption, it is in need of routing protocol security. In this paper, we propose an efficient and secure route discovery protocol for ad hoc network using symmetric key cryptography. This protocol has small computation loads at each hop using symmetric key cryptography. In the Route Reply, encryption/decrytion are used to guard against active attackers disguising a hop on the network.

• International Journal of Computer Science & Network Security
• /
• v.21 no.12
• /
• pp.53-60
• /
• 2021

Many standard methods are used for secret text files and secrete short messages cryptography, these methods are efficient when the text to be encrypted is small, and the efficiency will rapidly decrease when increasing the text size, also these methods sometimes have a low level of security, this level will depend on the PK length and sometimes it may be hacked. In this paper, a new method will be introduced to improve the data protection level by using a changeable secrete speech file to generate PK. Highly Secure Data Encryption (HSDE) method will be implemented and tested for data quality levels to ensure that the HSDE destroys the data in the encryption phase, and recover the original data in the decryption phase. Some standard methods of data cryptography will be implemented; comparisons will be done to justify the enhancements provided by the proposed method.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.10 no.3
• /
• pp.37-48
• /
• 2000

서울Visual cryptography scheme is a simple method in which can be directly decoded the secret information in human visual system without performing any cryptographic computations. This scheme is a kind of secret sharing scheme in which if a secret of image type is scattered to n random images(slides) and any threshold (or more) of them are stacked together the original image will become visible. In this paper we consider (2, n) visual cryptography scheme and propose a new construction method in which the number of expanded pixels can be reduced by using the sample matrix. The proposed scheme can futhermore distribute the multiple secret image to each group according to the difference of relative contrast.

• International Journal of Computer Science & Network Security
• /
• v.21 no.3
• /
• pp.60-70
• /
• 2021

In this paper we study the problem of implementation of security issues of blue tooth, especially secure simple pairing, with the help of an efficient four user authenticated key (4UAK) for an elliptic curve cryptography (ECC). This paper also deals with the design, implement and performance evaluation of secure simple pairing (SSP) using an elliptic curve cryptography, such as Diffie Hellman protocol when four users are involved. Here, we also compute the best, worst and average case step counts (time complexities). This work puts forth an efficient way of providing security in blue tooth. The time complexity of O(n⁴) is achieved using Rabin Miller Primality methodology. The method also reduces the calculation price and light communication loads.