Nowadays, the increase in the number of mobile users and cellular traffic leads to new challenges in the fifth-generation (5G) of cellular networks. The increase in the demand for high data rates brings challenges like scalability and flexibility in the 5G network. Software-defined networking (SDN) is a network paradigm that separates the control plane and data plane in the network and ease the management of the network. In this work, an SDN based 5G core architecture is proposed, in order to introduce flexibility and ease of management in the network. Another benefit of using SDN is to make the network vendor-independent. Furthermore, the explanation of initial attachment and handover procedures in the proposed architecture is provided. A network simulator is built to evaluate the performance of proposed architecture, in terms of end-to-end delay, throughput and resource utilization of controller, under different network factors. A performance comparison, in terms of end-to-end delay, between proposed SDN based 5G architecture and traditional 5G architecture is provided. Results show that the proposed architecture provides 18% to 62% less end-to-end delay, under different factors for different procedures, compared to the traditional 5G architecture. A comparison with previous works is also provided, which indicates similar trends in delay between our work and previous studies.

Cloud computing is an essential technology for the future of the Information Technology (IT) industry. However, the cloud security level is identified as the biggest challenge facing cloud providers and a major concern for cloud adopters. Economic Denial of Sustainability (EDoS) attack is one of the major threats targeting the cloud. The EDoS attack exploits the cloud elasticity and auto scaling features to charge a cloud adopter bill an excessive amount of cost leading to large-scale service withdrawal or bankruptcy. A novel reactive approach referred to as the EDoS Attack Defense Shell (EDoS-ADS) is proposed to mitigate EDoS attacks while taking into account most of the existing mitigation techniques drawbacks. Specifically, the EDoS-ADS has the ability to identify the legitimacy of clients even if they belong to a Network Address Translation (NAT) based network. Thus, EDoS-ADS is the first known technique that effectively prevents an EDoS attack from blocking an entire NAT-based network from accessing the cloud. The EDoS-ADS effectiveness in terms of response time, CPU utilization, throughput, and cost is evaluated using a CloudSim simulator. The simulation results show that EDoS-ADS outperforms other mitigation techniques, and successfully differentiates between legitimate and attacker clients even when they belong to the same NAT-based network.

Routing discovery is a pivotal component of the communication stack in Low-power and Lossy Networks (LLNs). The IPv6 routing protocol for LLNs, termed RPL, has been recently standardized to provide routing discovery in a wide range of LLN-based deployments realizing the Internet of Things (IoT) vision. RPL was mainly designed with the assumption that the predominant traffic flow would be gathering data towards a single destination, typically the root node. However, node-to-node (N2N) communication, where the root is neither source nor destination, is a prime requirement in most of the LLN-based applications such as actuating, decision making, and controlling applications. RPL in its current form does not cater well to such applications where there is a good number of inward N2N traffic flows. In this paper, we propose a hybrid routing mechanism based on RPL for high N2N communications in LLNs referred to by HRPL. HRPL is implemented on Contiki and evaluated through extensive simulations on Cooja. HRPL is fully backward compatible with RPL where HRPL and RPL nodes can work together seamlessly in a hybrid network. Results show that HRPL provides a considerable improvement in packet delivery ratio relative to the standardized RPL-based modes and to the RPL-based opportunistic routing approach. While HRPL requires a slightly larger memory footprint more than that for RPL, HRPL manages to significantly reduce the control plane packets, number of hops, and MAC transmissions needed to successfully deliver N2N data packets. Accordingly, this is translated to lower packet delay and less energy consumption.

A new scheme using Field Programmable Gate Arrays (FPGAs) to secure IoT data processing in public clouds against various attacks (including attacks from insiders) is proposed. The proposed scheme supports various business models involving multiple parties and allow the data owner to give temporary access to IoT data to specific clients at a public market place (the cloud). The scheme achieves perfect forward secrecy, provides FPGA authentication, a secure way to establish a symmetric session key between the on-cloud FPGA, the IoT device and the client, and allows user’s configuration integrity check while running in the cloud FPGA. A symmetric proxy re-encryption (PRE) scheme is used to support the publish/subscribe mode of operation of IoTs. A complete prototype has been implemented to show the feasibility of the proposed scheme. Formal verification of the proposed protocol verified that it does not have any vulnerabilities. Experimental results showed that an FPGA implementation of the proposed PRE was 6x faster than the SW implementation in transforming a ciphertext of size 1 Gb.

A new scheme for securing users' data and applications in public clouds and data centers using Field Programmable Gate Arrays (FPGAs) has been developed. This scheme incorporates all necessary protocols, hardware, and software components to provide protection against many known potential attacks including internal attacks. It achieves perfect forward secrecy, provides FPGA authentication and integrity checks, and securely establishes a symmetric session key between the user and the FPGA. A complete prototype has been implemented to show the feasibility of the proposed scheme with current FPGAs. Experimental results showed that an FPGA-based compute node can be set up in a cloud in 3.36s; 12.6 times faster than booting a medium-size conventional Virtual Machine (VM) on the same cloud. Based on the average global Internet speed, the time it takes to set up the FPGA-based machine from anywhere in the world was estimated to be 15s. Also, running an experimental secure image processing application on the FPGA took 50% less time than running the same application on a conventional state-of-the art processor (without a secure container).

Peer-to-peer (P2P) content distribution and file sharing systems aim to facilitate the dissemination of large files over unreliable networks. Network coding is a transmission technique that has captured the interest of researchers because of its ability to increase throughput and robustness of the network, and decrease the download time. In this survey paper, we extensively summarize, assess, compare, and classify the most recently used techniques to improve P2P content distribution systems performance using network coding. To the best of our knowledge, this survey is the first comprehensive survey that specifically focuses on the performance of network coding based P2P file sharing systems.