Biblio

With the evolution of computing from using personal computers to use of online Internet of Things (IoT) services and applications, security risks have also evolved as a major concern. The use of Fog computing enhances reliability and availability of the online services due to enhanced heterogeneity and increased number of computing servers. However, security remains an open challenge. Various trust models have been proposed to measure the security strength of available service providers. We utilize the quantized security of Datacenters and propose a new security-based service broker policy(SbSBP) for Fog computing environment to allocate the optimal Datacenter(s) to serve users' requests based on users' requirements of cost, time and security. Further, considering the dynamic nature of Fog computing, the concept of dynamic reconfiguration has been added. Comparative analysis of simulation results shows the effectiveness of proposed policy to incorporate users' requirements in the decision-making process.

Among the several threats to cyber services Distributed denial-of-service (DDoS) attack is most prevailing nowadays. DDoS involves making an online service unavailable by flooding the bandwidth or resources of a targeted system. It is easier for an insider having legitimate access to the system to circumvent any security controls thus resulting in insider attack. To mitigate insider assisted DDoS attacks, this paper proposes a moving target defense mechanism that involves isolation of insiders from innocent clients by using attack proxies. Further using the concept of load balancing an effective algorithm to detect and handle insider attack is developed with the aim of maximizing attack isolation while minimizing the total number of proxies used.

The increased number of cyber attacks makes the availability of services a major security concern. One common type of cyber threat is distributed denial of service (DDoS). A DDoS attack is aimed at disrupting the legitimate users from accessing the services. It is easier for an insider having legitimate access to the system to deceive any security controls resulting in insider attack. This paper proposes an Early Detection and Isolation Policy (EDIP)to mitigate insider-assisted DDoS attacks. EDIP detects insider among all legitimate clients present in the system at proxy level and isolate it from innocent clients by migrating it to attack proxy. Further an effective algorithm for detection and isolation of insider is developed with the aim of maximizing attack isolation while minimizing disruption to benign clients. In addition, concept of load balancing is used to prevent proxies from getting overloaded.

Real world applications of Wireless Sensor Networks such as border control, healthcare monitoring and target tracking require secure communications. Thus, during WSN setup, one of the first requirements is to distribute the keys to the sensor nodes which can be later used for securing the messages exchanged between sensors. The key management schemes in WSN secure the communication between a pair or a group of nodes. However, the storage capacity of the sensor nodes is limited which makes storage requirement as an important parameter for the evaluation of key management schemes. This paper classifies the existing key management schemes proposed for WSNs into three categories: storage inefficient, storage efficient and highly storage efficient key management schemes.

Mobile cloud computing is a combination of mobile computing and cloud computing that provides a platform for mobile users to offload heavy tasks and data on the cloud, thus, helping them to overcome the limitations of their mobile devices. However, while utilizing the mobile cloud computing technology users lose physical control of their data; this ultimately calls for the need of a data security protocol. Although, numerous such protocols have been proposed,none of them consider a cloudlet based architecture. A cloudlet is a reliable, resource-rich computer/cluster which is well-connected to the internet and is available to nearby mobile devices. In this paper, we propose a data security protocol for a distributed cloud architecture having cloudlet integrated with the base station, using the property of perfect forward secrecy. Our protocol not only protects data from any unauthorized user, but also prevents exposure of data to the cloud owner.