No abstract

Abstrak-Salah satu teknik penyembunyian data yang populer adalah steganografi. Teknik ini dapat mengecoh pihak penyadap data sehingga informasi rahasia tetap aman. Steganografi dapat digunakan dengan menerapkan sejumlah algoritma dengan bantuan pemrosesan komputer. Algoritma steganografi yang sering diteliti antara lain least significant bit (LSB) dan most significant bit (MSB). LSB merupakan salah satu algoritma steganografi yang melakukan proses perhitungan bit dengan nilai paling kecil, sedangkan MSB melakukan proses yang sama namun dengan pilihan angka yang besar. LSB merupakan algoritma sederhana namun dapat digunakan pada proses steganografi, begitu pula dengan MSB. Penelitian ini membahas tentang uji performa algoritma LSB dan MSB dalam steganografi, baik dari segi kulitas hasil steganografi, dan ketahanan terhadap serangan. Alat ukur yang digunakan dalam penelitian adalah Mean Square Error (MSE), Peak Signal to Noise Ratio (PSNR), dan Coefficient Correlation (CC). Berdasarkan hasil penelitian metode LSB terbukti lebih baik dari segi kulitas, sedangkan ketahanan terhadap serangan MSB lebih unggul pada jenis serangan salt and pepper. Kata kunci-Steganografi, penyembunyian pesan, LSB, MSB, uji komparasi.Abstract-One of the most popular data hiding techniques is steganography. This technique can outwit the data tapper so that the secret information remains safe. Steganography can be used by applying a number of algorithms with the help of computer processing. Steganography algorithms that are often studied include Least Significant Bit (LSB) and Most Significant Bit (MSB). LSB is one of the steganography algorithms that perform the bit calculation process with the smallest value, while the MSB perform the same process but with a large number of choices. LSB is a simple algorithm but can be used in steganography process, as well as MSB. This study discusses the performance test of LSB and MSB algorithm in steganography, both in terms of quality of steganography, and resistance to attack. The measuring instruments used in this research are Mean Square Error (MSE), Peak Signal to Noise Ratio (PSNR), and Coefficient Correlation (CC). Based on the results of research LSB method proved better in terms of quality, whereas resistance to MSB attacks superior to the type of attack salt and pepper.

Server is a computer system that provides the kind of service in a computer network. One of the functions of the server is as data storage. Computers servers with high availability values are generally referred to as High Availability (HA) Server. HA enables a server can be operational in a sustainable manner for long periods of time. Now, HA has been combined with a cluster technique known as High Availability Clusters or failover cluster. In this research the author intends to apply, analyze, and implement a network file server that has a high availability of service. Researchers used a pacemaker as cluster resource management, Corosync as cluster messaging service and DRBD for the synchronization of data if a failover occurs and measured network performer cluster file system that does have a high availability service. The result is a network file system or the availability of the cluster has a value of 99.998% availability, which means it has a High Availability. The server network file system failover cluster meets the conditions, which, if the primary server (master) dies it will be replaced by a slave server.

Abstract-Utilization of document files does not guarantee the security of those documents. There are acts of plagiarism of txt and doc files. Converting files into PDF can help secure the files, because PDF can not be easily plagiarized and a password can be embedded into the files. But, nowadays, PDF files also can be modified by other parties, thus, reducing the security of the files. This paper utilizes factor of prime and random numbers in cryptography using ElGamal algorithm to encrypt PDF plaintext documents into cipher text. This research uses experimental research with some experiments of encryption and decryption. The data analysis type is quantitative with non-parametric statistic. This technique is implemented to analyze the final result of experiments. The research is conducted by doing 20 times encryption using random keys. The result shows the successfulness of encryption process. The process begins by converting each character from the plaintext using ASCII table to a decimal number. ElGamal algorithm calculation is then applied using prime and random numbers to generate the keys. This process makes ElGamal algorithm superior to other algorithm. The result is character value used in the decryption process. The output of the encryption process is an encrypted PDF document (ciphertext). The results show that the combinations of prime and random numbers are successfully generated in the encryption process using ElGamal algorithm.Intisari-Pemanfaatan file dokumen txt dan doc ternyata tidak menjamin dokumen tersebut aman. Terdapat pihak yang melakukan tindakan plagiat terhadap file txt dan doc, sehingga muncul inisiatif untuk mengamankan file tersebut dengan melakukan konversi file ke PDF untuk alasan keamanan. Keunggulan file PDF yang tidak mudah diplagiat serta sudah dilengkapi dengan password ternyata juga dinyatakan sudah tidak aman lagi, karena masih mudah dimodifikasi oleh pihak lain. Dalam makalah ini, faktor bilangan prima dan bilangan acak pada kriptografi dengan algoritme ElGamal digunakan untuk mengenkripsi dokumen plaintext PDF menjadi dokumen ciphertext yang tidak mudah dimodifikasi. Penelitian menggunakan jenis eksperimental dengan beberapa percobaan proses enkripsi maupun dekripsi dengan variabel bilangan prima dan bilangan acak. Analisis data yang digunakan adalah analisis kuantitatif dengan statistik nonparametrik. Penerapan teknik ini berupa analisis hasil akhir file percobaan proses enkripsi serta dekripsi. Dari hasil uji coba sebanyak 20 kali proses enkripsi menggunakan kunci secara acak, dinyatakan file berhasil melalui proses enkripsi. Proses enkripsi diawali dengan konversi masing-masing karakter dari plaintext dengan menggunakan tabel ASCII menjadi bilangan desimal. Proses selanjutnya berupa perhitungan algoritme ElGamal dengan memanfaatkan bilangan acak prima serta bilangan acak lainnya untuk membangkitkan kunci. Hal inilah yang meyebabkan algoritme ElGamal lebih unggul dibanding algoritme lainnya. Hasil proses enkripsi berupa nilai karakter yang digunakan sebagai proses dekrip...

The rapid development of technology not only has a positive impact, but also can have a negative impact such as the development of cyber crime that can cause messages to be unsafe. Message security can be protected using cryptography to convert messages into secret passwords. Steganography is a technique of hiding messages by inserting messages into images that are used to increase message security. In this study, it discusses a combination of hill cipher and LSB algorithms to secure messages. The message used is a 3-bit grayscale image for steganography and text messages with 32, 64 and 128 characters for cryptography. The measuring instruments used in this study are MSE, PSNR, Entropy and travel time (CPU time). Test results prove an increase in security without too damaging the image. This is evidenced by the results of the MSE trial which has a value far below the value 1, the PSNR is> 65 dB with a range of entropy values of 5 to 7, and travel times are almost the same.