Mazleena Salleh

Enhanced chaotic image encryption algorithm based on Baker's map

Imaging has gained importance due to the improvements of performances in computer speed, media storage and network bandwidth. Along with this advancement, the fundamental issue of image security has become a major concern and because of this reason, research in image confidentiality has gained popularity amongst security experts. This paper discusses an alternative chaotic image encryption based on Bakers map. This enhanced symmetric-key algorithm can support a variable-size image as opposed to the algorithm which is mainly based on Bakers map that requires only square image for encryption. In addition, the algorithm also includes other functions such as password binding and pixel shifting to further strengthen the security of the cipher image. The algorithm also supports two modes of operation namely EBC and CBC. The number of iterations to be performed can vary depending on the security level required by the user. The paper also includes an example of image encryption. From the analysis done, it shows that the security level is high even though keys that are found to be weak keys for Bakers map algorithm are being used in the algorithm.

Secure E-voting with blind signature

With a rapid growth in computer networks, many people can access the network through the Internet and therefore an electronic voting can be a viable alternative for conducting an election. An electronic voting system must attempt to achieve at least the same level of security as ordinary elections. We have developed an electronic voting system, E-voting for a general election. The E-voting system employs cryptographic techniques to overcome the security issues in the election process. In this system, voters privacy is guaranteed by using a blind signature for confidentiality and voters digital signature for voters authentication. E-voting is implemented by employing Java socket technology and BouncyCastle cryptography provider. The provider, which is an open source library, is used to provide the secure communication channel. The voters private key for digital signature is protected by using password-based encryption with SHA and Twofish-CBC algorithm so that only valid voter can use it.

Enhanced Key Expansion for AES-256 by using Even-Odd method

This study is conducted to determine an alternative, creative method for designing Key Expansion in AES-256 that is called Even-Odd (E-O) method. The proposed algorithm consists of two parts. The first part is Key Expansion and the second part is E-O Select Round Key. The cipher key is 256 bits as an input and the output is fifteen round keys that are 128 bits and include 14 round keys and one pre round key. The element of confusion is highly being concerned in this algorithm and efficiency is improved compared to the classic existing algorithms. The avalanche effect of E-O method is highly improved than classic method. In addition, the concept of weak key is eliminated from the mentioned algorithm. The results also show that the performance of the sub-keys generation is equivalent to the classic AES algorithm.

Adaptive watermarking for printed document authentication

The rapid growth in information and communication technologies provides ways for some people to forge printed documents. Digital watermarking is widely used for authenticating digital documents. By embedding some watermarks in the printed documents in a way not to be observed by human eyes we may stop these forgeries. While a printed document requires another procedure to extract the embedded watermark and this process normally suffers from image distortion which is made by either printers quality or scanners precision. In this paper, the proposed watermarking scheme is capable of authenticating the embedded watermark in the printed documents. There is a factor to regulate the amount of watermark to be embedded in each specified partition of the image known as regulation factor. In terms of security, the embedding process employs different values of regulation factor. As the watermarking scheme uses a matrix of regulation factors rather than a fixed regulation factor, it is considered as an adaptive embedding. On the other hand, once the watermarked document is printed, it is required to be scanned. The geometric distortion is required to be removed from the scanned document including watermark in order to improve the quality of the retrieved watermark so that the extracted watermark is normalized. By doing this, the extracted watermark is clearer for visual authentication.

Enhanced AES-CCMP key structure in IEEE 802.11i

This study is conducted to establish an alternative, creative technique for key structure of AES-Counter Mode with Cipher Block Chaining Message Authentication Code Protocol (AES-CCMP) encryption method in IEEE 802.11i. The proposed method modifies AES-CCMP key length from 128 bits to 256 bits through recommending three distinctive solutions including Random NonceKey, Four Way Handshake alteration and Pseudo Random Function (PRF). Besides, the memory usage and the avalanche effect of the proposed method and the traditional method are compared. The avalanche effect of the proposed method is near to optimized style and the memory usage is approximately close to memory usage of classic AES-CCMP. In addition in the mentioned method, pre computation attack is completely eliminated.

Improving confidentiality of AES-CCMP in IEEE 802.11i

This paper proposed a new method for Advanced Encryption Standard-Counter Mode with Cipher Block Chaining Message Authentication Code Protocol (AES-CCMP) to eliminate security issues in current method including small effective key length and predictable structure of Nonce which increases the probability of Time-Memory Trade-Off (TMTO) attack. Proposed method suggests three solutions to overcome the mentioned weaknesses including random NonceKey, four way handshake alteration and Pseudo Random Function (PRF). Besides, proposed and classic methods are compared in terms of TMTO attack probability, avalanche effect, changes in neighbor blocks, memory usage and execution time. According to the results, the proposed method is completely resistant to TMTO attack. In addition, avalanche effect and change in neighbor blocks of proposed method are so near to optimized state and also, classic and proposed methods are approximately the same in case of memory usage and execution time.

Preventing TMTO Attack in AES-CCMP in IEEE 802.11i

This study is conducted to establish an alternative, creative technique for the structure of Advanced Encryption Standard-Counter Mode with Cipher Block Chaining Message Authentication Code Protocol (AES-CCMP) key in IEEE 802.11i. the structure of proposed method increase the length of AES-CCMP key from 128 bits to 256 bits to eliminate Time-Memory Trade-Off (TMTO) attacks by using three proposed solutions including Random NonceKey, Four Way Handshake alteration and Pseudo Random Function (PRF). Besides, two proposed and classic methods are compared in terms of TMTO attack probability, avalanche effect, changes in neighbor blocks, memory usage and execution time. According to the results, the proposed method is completely resistant to TMTO attack. In addition, avalanche effect and change in neighbor blocks of proposed method are so near to optimized state and also, two classic and proposed methods are approximately the same in case of memory usage and execution time.

The Sign Tales of Hurst Parameter: A Revisit

Network traffic measurement studies have shown the presence of self-similar behavior in both local area and wide area traffic traces. In this study we investigated the magnitude of the self-similarity behavior of network traffic and its Hurst measurement, H. Our study has revealed several characteristics of H based on the network traffic changes. From the finding, H can be used as traffic load indicated only if the sampling size is large. On the other hand for a smaller sampling size, H can be used to indicate the change in traffic pattern. However network traffic does not always exhibit self-similarity property. Activities such as peer-to-peer can steer the traffic to lose this property.