Abstract

Digital forensics is a class of forensic science interested with the use of digital information produced, stored and transmitted by various digital devices as source of evidence in investigations and legal proceedings. Digital forensics can be split up to several classes such as computer forensics, network forensics, mobile forensics, cloud computing forensics, and IoT forensics. In recent years, cloud computing has emerged as a popular computing model in various areas of human life. However, cloud computing systems lack support for computer forensic investigations. The main goal of digital forensics is to prove the presence of a particular document in a given digital device. This paper presents a comprehensive survey of various frameworks and solutions in all classes of digital forensics with a focus on cloud forensics. We start by discussing different forensics classes, their frameworks, limitations and solutions. Then we focus on the methodological aspect and existing challenges of cloud forensics. Moreover, the detailed comparison discusses drawbacks, differences and similarities of several suggested cloud computing frameworks providing future research directions.

Mobile Ad-hoc network (MANET) is an infrastructure-less and dynamic network. Routing in such a network is a challenge due to the mobility of its nodes. Multipath routing protocols try to improve the performance by finding more than one path towards the destination which could be kept as alternatives should the main path breaks. Stability-based Partially Disjoint AOMDV (SPDA) protocol has been proposed to tackle problems resulted from the very dynamic topology of MANETs. SPDA finds partially disjoint paths that are more stable than the maximally disjoint ones in order to increase paths lifetime as well as the availability of such multipaths. When choosing partially disjoint paths, SPDA does not take into consideration the number of hops of each path. Moreover, SPDA transmits packets over the shortest path until it becomes invalid before it tries to utilize other alternative paths. In this paper we improve SPDA by adding the number of nodes each path passes through to the selection criteria. In the Improved SPDA (ISPDA), the available alternative paths have been utilized to transmit packets in parallel. We compare the SPDA and ISPDA regarding the throughput and delay. Results show the superiority of ISPDA over the original one.

number of logical operations and the need for readdressing of nodes every time a new level is add to the network. This negatively impacts the performance of the network as it increases the execution time of these algorithms. In this paper we propose an improved optimal point to point routing algorithm for Hex-Cell network. The algorithm is based on dividing the Hex-Cell topology into six divisions, hence the name Section Based Hex-Cell Routing (SBHCR). The SBHCR algorithm is simple and preserves the advantage of the addressing scheme proposed for the Hex-Cell network. It does not depend on the depth of the network topology which leads to overcome the issue of readdressing of nodes every time a new level is added. Evaluation against two previously suggested routing algorithms hasshown the superiority of SBHCR in term of less logical operations.

Cryptographic applications are becoming increasingly more important in today's world of data exchange, big volumes of data need to be transferred safely from one location to another at high speed. In this paper, the parallel implementation of blowfish cryptography algorithm is evaluated and compared in terms of running time, speed up and parallel efficiency. The parallel implementation of blowfish is implemented using message passing interface (MPI) library, and the results have been conducted using IMAN1 Supercomputer. The experimental results show that the runtime of blowfish algorithm is decreased as the number of processors is increased. Moreover, when the number of processors is 2, 4, and 8, parallel efficiency achieves up to 99%, 98%, and 66%, respectively.