With the massive inflation of newly developed technologies, recourse to data has become a necessity in light of the current inflation and excessive need dominating the world and developed societies. According to the control of millions of smart devices and sensors connected to an interconnected and controlled automated system within installed scales due to the services provided by IOT devices through the created fog layer that connects the cloud centers and those devices, in addition, very large amounts of that data including public and private are passed through the connection of Internet of Things devices to each other. Smart and advanced networks as one of the fog computing applications play a prominent and accurate role in the infrastructure for reliable and sound data transmission. Accordingly, the process of data aggregation is an important and common matter in the world of fog-enhancing Internet of Things, so preserving the privacy of that data is a matter of concern, and based on this principle, we propose in this paper a model for data aggregation that maintains privacy using a foggy computing environment called PPFDA (privacy preserving based- fog computing data aggregation). We use in our scheme DF homomorphic cryptosystem as it consider one of the aggregation models that ensures the privacy purpose. The theoretical results and analyzes show that our design is ensuring the privacy of data during collection using an algorithm of DF. The results confirm that the proposed scheme achieves security and privacy purposes in modern network systems for the Internet of things based in fog computing. In addition, it contributes significantly to the efficient performance of storage operations.

The huge availability and prosperity of net technology results in raised on-line media sharing over the cloud platform which has become one of the important resources and tools for development in our societies. So, in the epoch of enormous data great amount of sensitive information and transmission of different media transmitted over the net for communication. And recently, fog computing has captured the world's attention due to their inherent features relevant compared to the cloud domain, But this push to head for many issues related to data security and privacy in fog computing which it's still under studied in their initial juncture. Therefore, in this paper, we will review a security system that relies on encryption as a kind of effective solution to secure image data. We use an approach of using chaotic map plus space curve techniques moreover the confusion and diffusion strategies are carried out utilizing Hilbert curvature and chaotic map such as two-dimensional Henon map (2D-HM) to assert image confusion with pixel level permutation .Also we relied in our system the way of shuffling the image with blocks and use a key for each block, which is chooses randomly to have a high degree of security. The efficiency of the proposed technique has been tested utilizing different investigations like analysis of entropy [7.9993], NPCR [99.6908%] and finally UACI [33.6247%]. Analysis of results revealed that the proposed system of image encryption technique has favorable effects, and can achieve a good results moreover it fights different attacks and by comparing with another techniques denote that our proposed fulfills high security level with high quality.