Biblio

Today, the huge amount of data was using in organizations around the world. This huge amount of data needs to process so that we can acquire useful information. Consequently, a number of industry enterprises discovered great information from shopper purchases found in any respect times. In data mining, the most important algorithms for find frequent item sets from large database is Apriori algorithm and discover the knowledge using the association rule. Apriori algorithm was wasted times for scanning the whole database and searching the frequent item sets and inefficient of memory requirement when large numbers of transactions are in consideration. The improved Apriori algorithm is adding and calculating third threshold may increase the overhead. So, in the aims of proposed research, Improved Apriori algorithm with LinkedList and hash tabled is used to mine frequent item sets from the transaction large amount of database. This method includes database is scanning with Improved Apriori algorithm and frequent 1-item sets counts with using the hash table. Then, in the linked list saved the next frequent item sets and scanning the database. The hash table used to produce the frequent 2-item sets Therefore, the database scans the only two times and necessary less processing time and memory space.

Mobile Ad-hoc Networks (MANETs) have gained popularity both in research and in industrial fields. This is due to their ad hoc nature, easy deployment thanks to the lack of fixed infrastructure, self-organization of its components, dynamic topologies and the absence of any central authority for routing. However, MANETs suffer from several vulnerabilities such as battery power, limited memory space, and physical protection of network nodes. In addition, MANETs are sensitive to various attacks that threaten network security like Blackhole attack in its different implementation (single and multiple). In this article, we present the simulation results of single and multiple Blackhole attack in AODV and OLSR protocols on using NS-3.27 simulator. In this simulation, we took into consideration the density of the network described by the number of nodes included in the network, the speed of the nodes, the mobility model and even we chose the IEEE 802.11ac protocol for the pbysicallayer, in order to have a simulation, which deals with more general and more real scenarios. To be able to evaluate the impact of the attack on the network, the Packet delivery rate, Routing overhead, Throughput and Average End to End delay have been chosen as metrics for performance evaluation.