Search results

We study a scenario where a monitor is interested in the freshest possible update from a remote sensor. The monitor also seeks to minimize the number of updates that exceed a certain freshness threshold, beyond which, the information is deemed to be too old. Previous work has presented results for First Come First Served (FCFS) systems. However, it has been shown that Last Come First Served (LCFS)

In this thesis, we investigate and develop new methods for efficient and functional use of resources in edge networks. Setting this work aside from previous work, we study User Generated Content (UGC) such as social media information and data generated in the new emerging Internet of Things systems. We present efficient solutions for placing such content and managing which network resources should

This survey overviews the potential use of cryptographic primitives in the fifth-generation mobile communications system (aka 5G) and beyond. It discusses the new security challenges that come with 5G and presents the upcoming security architecture. It shows the use of current cryptographic algorithms and discusses new algorithms or modifications of existing ones, that can be relevant. It also dis

Mobile and wireless data are in increasing demand worldwide. New trends such as the Internet of Things paradigm and the Smart City paradigm describe scenarios comprising thousands of devices all exchanging information amongst themselves wirelessly --- or through the WAN to another device, possibly connected to another WLAN. Operators and radio engineers are faced with the problem of designing effi

The digital twin is a rather new industrial control and automation systems concept. While the approach so far has gained interest mainly due to capabilities to make advanced simulations and optimizations, recently the possibilities for enhanced security have got attention within the research community. In this paper, we discuss how a digital twin replication model and corresponding security archit

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

Efficient protection of huge amount of IoT produced data is key for wide scale data analytic services. The most efficient way is to use pure symmetric encryption as that allows both fast decryption at the analytic engine side as well as energy efficient encryption at the IoT side. However, symmetric encryption can only be performed if there is a way to directly map an encrypted object to the corre

The Bit Flipping algorithm is a hard decision decoding algorithm originally designed by Gallager in 1962 to decode Low Density Parity Check Codes (LDPC). It has recently proved to be much more versatile, for Moderate Parity Check Codes (MDPC) or Euclidean metric. We further demonstrate its power by proposing a noisy Euclidean version of it. This tweak allows to construct a lattice based key exchan

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

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

The fresh re-keying scheme is a countermeasure designed to protect low-cost devices against side-channel attacks. In this paper, we present a new birthday-type attack based on a refined reduction to RING-LPN with a reducible polynomial. Compared with the previous research, our algorithm significantly reduces the time complexity in the 128-bit leakage model—with an SNR equal to 8.21 and at most 2

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

Although a number of different medium access control (MAC) schemes are adopted for wireless multi-hop networks, time division multiple access (TDMA) approaches based on a periodic frame of time slots are the most common when very high efficiency is needed in terms of use of radio and energy resources. Efficient resource usage is typically based on parallel compatible transmissions from multiple no

Algorithms for secure encryption in a post-quantum world are currently receiving a lot of attention in the research community. One of the most promising such algorithms is the code-based scheme called QC-MDPC, which has excellent performance and a small public key size. In this work we present a very efficient key recovery attack on the QC-MDPC scheme using the fact that decryption uses an iterati

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 Learning with Errors problem (LWE) is one of the main candidates for post-quantum cryptography. At Asiacrypt 2017, coded-BKW with sieving, an algorithm combining the Blum-Kalai-Wasserman algorithm (BKW) with lattice sieving techniques, was proposed. In this paper, we improve that algorithm by using different reduction factors in different steps of the sieving part of the algorithm. In the Rege