14 research outputs found
Bandwidth Allocation Mechanism based on Users' Web Usage Patterns for Campus Networks
Managing the bandwidth in campus networks becomes a challenge in recent years. The limited bandwidth resource and continuous growth of users make the IT managers think on the strategies concerning bandwidth allocation. This paper introduces a mechanism for allocating bandwidth based on the users’ web usage patterns. The main purpose is to set a higher bandwidth to the users who are inclined to browsing educational websites compared to those who are not. In attaining this proposed technique, some stages need to be done. These are the preprocessing of the weblogs, class labeling of the dataset, computation of the feature subspaces, training for the development of the ANN for LDA/GSVD algorithm, visualization, and bandwidth allocation. The proposed method was applied to real weblogs from university’s proxy servers. The results indicate that the proposed method is useful in classifying those users who used the internet in an educational way and those who are not. Thus, the developed ANN for LDA/GSVD algorithm outperformed the existing algorithm up to 50% which indicates that this approach is efficient. Further, based on the results, few users browsed educational contents. Through this mechanism, users will be encouraged to use the internet for educational purposes. Moreover, IT managers can make better plans to optimize the distribution of bandwidth
Implementation of Modified AES as Image Encryption Scheme
Since images have bigger size than text, a faster encryption algorithm is needed to provide higher security in digital images. The paper presents a modified AES algorithm that address the requirement in image encryption. The modified algorithm used bit permutation in replacement of MixColumns to reduce the computational requirement of the algorithm in encrypting images. Results of the study show that the modified algorithm exhibited faster encryption and decryption time in images. The modified algorithm also achieved a good result in the key sensitivity analysis, histogram analysis, information entropy, the correlation coefficient of adjacent pixels, Number of Pixel Change Rate and Unified Average Change Intensity making the modified algorithm resistant to statistical and differential attack
QR Code Integrity Verification Based on Modified SHA-1 Algorithm
The modified SHA-1 algorithm was applied in the data integrity verification process of certificates with QR code technology. This paper identified the requirements needed in the certificate verification that uses the modified SHA-1. The application was tested using legitimate and fraudulent certificates. Based on the results, the application successfully generated QR codes, printed certificates, and verified certificates with 100% accuracy. During the trial run of the app, four test cases were seen which involves correct names and QR codes, and three other possible test cases of faking certificates such as modification of the name, regeneration of QR codes using valid hash and a fake name, and modification of the QR code. Although these cases exist, the app successfully verified all thirty certificates correctly. Also, it is noticed that during the scanning, the smartphone camera should be in focus to capture the QR code clearly
An Improved Overlapping Clustering Algorithm to Detect Outlier
MCOKE algorithm in identifying data objects to multi cluster is known for its simplicity and effectiveness. Its drawback is the use of maxdist as a global threshold in assigning objects to one or more cluster while it is sensitive to outliers. Having outliers in the datasets can significantly affect the effectiveness of maxdist as regards to overlapping clustering. In this paper, the outlier detection is incorporated in MCOKE algorithm so that it can detect and remove outliers that can participate in the calculation of assigning objects to one or more clusters. The improved MCOKE algorithm provides better identification of overlapping clustering results. The performance was evaluated via F1 score performance criterion. Evaluation results revealed that the outlier detection demonstrated higher accuracy rate in identifying abnormal data (outliers) when applied to real datasets
A New Approach in Expanding the Hash Size of MD5
The enhanced MD5 algorithm has been developed by expanding its hash value up to 1280 bits from the original size of 128 bit using XOR and AND operators. Findings revealed that the hash value of the modified algorithm was not cracked or hacked during the experiment and testing using powerful bruteforce, dictionary, cracking tools and rainbow table such as CrackingStation, Hash Cracker, Cain and Abel and Rainbow Crack which are available online thus improved its security level compared to the original MD5. Furthermore, the proposed method could output a hash value with 1280 bits with only 10.9 ms additional execution time from MD5. Keywords: MD5 algorithm, hashing, client-server communication, modified MD5, hacking, bruteforce, rainbow table
Securing Electronic Medical Records Using Modified Blowfish Algorithm
EMR helped improve services to patients by delivering organization and accuracy of patient information, but issues regarding security breaches and medical identity theft are growing concerns. This paper enhance the current EMR system by integrating modified encryption. The simulation used modified Blowfish algorithm in an EMR system that focuses on four goals: 1) define the requirements, 2) design and identify features, 3) develop the EMR incorporating added security mechanism using modified Blowfish algorithm, and 4) test the application with sample data. Based on the results, the incorporation of the encryption was successful based on testing and checking done on the input terminal and the database server. Data inputted on the EMR system was successfully encrypted before transmission and decrypted only on the terminal for viewing. Performance results show that without encryption, saving took an average of 87.8ms while encrypted, it acquired 88.8ms, a difference of 1ms can be noted. The minimal difference is because of the size of the data. The average decryption time of all records using modified algorithm took 1342ms while using plaintext took 1322ms. The decryption time is higher by 20ms due to the application of the decryption algorithm
A modified genetic algorithm with a new crossover mating scheme
This study introduced the Inversed Bi-segmented Average Crossover (IBAX), a novel crossover operator that enhanced the offspring generation of the genetic algorithm (GA) for variable minimization and numerical optimization problems. An attempt to come up with a new mating scheme in generating new offspring under the crossover function through the novel IBAX operator has paved the way to a more efficient and optimized solution for variable minimization particularly on premature convergence problem using GA. A total of 597 records of student-respondents in the evaluation of the faculty instructional performance, represented by 30 variables, from the four State Universities and Colleges (SUC) in Caraga Region, Philippines were used as the dataset. The simulation results showed that the proposed modification on the Average Crossover (AX) of the genetic algorithm outperformed the genetic algorithm with the original AX operator. The GA with IBAX operator combined with rank-based selection function has removed 20 or 66.66% of the variables while 13 or 43.33% of the variables were removed when GA with AX operator and roulette wheel selection function was used
Modified AES Cipher Round and Key Schedule
In this paper, Advanced Encryption Standard was modified to address the lowdiffusion rate at the early rounds by adding additional primitive operationssuch as exclusive OR and modulo arithmetic in the cipher round. Furthermore,byte substitution and round constant addition were appended to the keyschedule algorithm. The modified AES was tested against the standard AESby means of avalanche effect and frequency test to measure the diffusion andconfusion characteristics respectively. The results of the avalanche effectevaluation show that there was an average increase in diffusion of 61.98% inround 1, 14.79% in round 2 and 13.87% in round 3. Consequently, the resultsof the frequency test demonstrated an improvement in the randomness of theciphertext since the average difference between the number of ones to zeros isreduced from 11.6 to 6.4 along with better-computed p-values. The resultsclearly show that the modified AES has improved diffusion and confusionproperties and the ciphertext can still be successfully decrypted and recoverback the original plaintext