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Internet of Things (IoT) is the next generation of network scenario where billions of devices are connected to the internet and capable to communicate with each other. However, they are especially vulnerable to Denial of Service (DoS) attack, which typically launched by overloading the server with bogus messages. Hence, unnecessary computation is performed by the IoT units, which can seriously wor
Discontinuous Reception (DRX) has been included in 4G-LTE as the main power saving mechanism for User Equipment (UE). However, the existing 3-state DRX model is not sufficient for new use cases introduced by 4G and 5G. For example, the device discovery process in Device to Device (D2D) communication has a significant impact on delay and power consumption, but the existing conventional 3-state DRX
In this paper we study resilience of TDMA-based wireless sensor networks to node failures. We investigate exploiting mutlicast routing for providing redundancy in the number of gateways used by data streams, so as to protect them against gateway failures. To do this, we develop an optimization model aiming at packet traffic throughput maximization composed of three mixed-integer programming proble
We investigate the trade-off between energy usage and (packet) throughput in wireless mesh networks performing machine-to-machine communication. For this we provide a novel mixed-integer programming formulation to maximise the throughput while maintaining minimal energy usage, together with an effective price-and-branch solution algorithm based on column generation. The resulting optimisation mode
Searchable symmetric encryption (SSE) schemes are commonly proposed to enable search in a protected unstructured documents such as email archives or any set of sensitive text files. However, some SSE schemes have been recently proposed in order to protect relational databases. Most of the previous attacks on SSE schemes have only targeted its common use case, protecting unstructured data. In this
Distinguishers and nonrandomness detectors are used to distinguish ciphertext from random data. In this paper, we focus on the construction of such devices using the maximum degree monomial test. This requires the selection of certain subsets of key and IV-bits of the cipher, and since this selection to a great extent affects the final outcome, it is important to make a good selection. We present
The evolution of Software-Defined Networking (SDN) has so far been predominantly geared towards defining and refining the abstractions on the forwarding and control planes. However, despite a maturing south-bound interface and a range of proposed network operating systems, the network management application layer is yet to be specified and standardized. It has currently poorly defined access contr
The paper considers multi-hop wireless mesh networks that serve multicast periodic packet traffic. The packets from each packet stream are generated at the stream's source node and traverse a number of wireless nodes in order to reach their multiple destination nodes. Packet periodicity means that a common repeatable frame of time slots is defined and that the packets to be transmitted arrive at t
NTRU is a public-key cryptosystem, where the underlying mathematical problem is currently safe against large-scale quantum computer attacks. The system is not as well investigated, as for example RSA, and the company behind NTRU has created the NTRU Challenges, to remedy this. These challenges consist of 27 different public keys of increasing size, where the task in each challenge is to calculate
Guo et al. recently presented a reaction attack against the QC-MDPC McEliece cryptosystem. Their attack is based on the observation that when a bit-flipping decoding algorithm is used in the QC-MDPC McEliece, then there exists a dependence between the secret matrix H and the failure probability of the bit-flipping algorithm. This dependence can be exploited to reveal the matrix H which constitutes
Flow thinning (FT) is an active traffic protection mechanism destined for communication networks with variable capacity of links, as for example wireless networks. In FT, end-to-end traffic demands are equipped with dedicated logical tunnels (for example MPLS tunnels) whose maximal capacity is subject to thinning in order to follow the fluctuations of the currently available link capacity. It foll
The presented work is motivated by Free Space Optics (FSO) communications. FSO is a well established wireless optical transmission technology considered as an alternative to radio communications for example in metropolitan wireless mesh networks. An FSO link is established by means of a laser beam between the transmitter and the receiver placed in the line of sight. A major disadvantage of FSO lin
Intel Software Guard Extensions (SGX) provides a trusted execution environment (TEE) to run code and operate sensitive data.SGX provides runtime hardware protection where both code and data are protected even if other code components are malicious.However, recently many attacks targeting SGX have been identified and introduced that can thwart the hardware defence provided by SGX.In this paper we p
Flow thinning (FT) is a traffic routing and protection strategy for communication networks whose links experience fluctuations in available capacity (as, e.g., in wireless networks). To cope with this phenomenon, end-to-end traffic demands are assigned dedicated tunnels (e.g., MPLS tunnels) whose nominal capacity is subject to thinning in order to account for variable capacity of the links, fluctu
In this paper we address the problem of resource allocation for alarm traffic in industrial Internet of Things networks using massive MIMO. We formulate the general problem of how to allocate pilot signals to alarm traffic such that delivery is guaranteed, while also minimising the number of pilots reserved for alarms, thus maximising the channel resources available for other traffic, such as indu
Software-Defined Networking (SDN) is a novel architectural model for cloud network infrastructure, improving resource utilization, scalability and administration. SDN deployments increasingly rely on virtual switches executing on commodity operating systems with large code bases, which are prime targets for adversaries attacking the network infrastructure. We describe and implement TruSDN, a frame
We implement the Grain-128AEAD stream cipher in hardware, using a 65 nm library. By exploring different optimization techniques, both at RTL level but also during synthesis, we first target high throughput, then low power. We reach over 33 GB/s targeting a high-speed design, at expense of power and area. We also show that, when targeting low power, the design only requires 0.23 $${\upmu }$$W runni
Cryptosystems based on Learning with Errors or related problems are central topics in recent cryptographic research. One main witness to this is the NIST Post-Quantum Cryptography Standardization effort. Many submitted proposals rely on problems related to Learning with Errors. Such schemes often include the possibility of decryption errors with some very small probability. Some of them have a som
We improve iterative decoding of the moderate density parity-check codes, recently suggested as code candidates in the McEliece public key cryptosystem. In case of bit-flipping (BF) decoder failure, the code parity-check matrix is extended by adding auxiliary variable nodes based on reliability information from the BF decoder. Then iterative decoding is applied to the extended parity-check matrix.
The central role of the certificate authority (CA) in traditional public key infrastructure (PKI) makes it fragile and prone to compromises and operational failures. Maintaining CAs and revocation lists is demanding especially in loosely-connected and large systems. Log-based PKIs have been proposed as a remedy but they do not solve the problem effectively. We provide a general model and a solutio
