A null space-based MAC scheme against pollution attacks to random linear network coding

Network Coding has significantly shown the achievable throughput and robustness in wireless Networks. However, network coding-enabled networks are susceptible to pollution attacks where a small number of polluted messages will propagate due to recoding and corrupt bunches of legitimate messages. Several lightweight Homomorphic Message Authentication Code (HMAC) schemes have been proposed for protecting the transmitted data against pollution attacks; however, most of them are not appropriate for wireless networks or cannot resist tag pollution attacks. In this paper, we present a computationally efficient null space-based homomorphic MAC scheme, for network coding-enabled wireless networks. The proposed scheme makes use of two types of tags (i.e., MACs and D-MACs) to provide resistance against data pollution and tag pollution attacks. Furthermore, we demonstrate that due to its lightweight nature, our proposed scheme incurs a minimal complexity compared to other related schemes

On Coding for Reliable Communication over Packet Networks

We present a capacity-achieving coding scheme for unicast or multicast over lossy packet networks. In the scheme, intermediate nodes perform additional coding yet do not decode nor even wait for a block of packets before sending out coded packets. Rather, whenever they have a transmission opportunity, they send out coded packets formed from random linear combinations of previously received packets. All coding and decoding operations have polynomial complexity. We show that the scheme is capacity-achieving as long as packets received on a link arrive according to a process that has an average rate. Thus, packet losses on a link may exhibit correlation in time or with losses on other links. In the special case of Poisson traffic with i.i.d. losses, we give error exponents that quantify the rate of decay of the probability of error with coding delay. Our analysis of the scheme shows that it is not only capacity-achieving, but that the propagation of packets carrying "innovative" information follows the propagation of jobs through a queueing network, and therefore fluid flow models yield good approximations. We consider networks with both lossy point-to-point and broadcast links, allowing us to model both wireline and wireless packet networks.Comment: 33 pages, 6 figures; revised appendi

Υλοποίηση προχωρημένων μεθόδων μετάδοσης δεδομένων με χρήση τεχνικών συνεργασίας κόμβων σε ασύρματες κάρτες

Η παρούσα διπλωματική εργασία αφορά μια εις βάθος μελέτη της δικτυακής κωδικοποίησης (network coding) και της εφαρμογής αυτής σε διάφορους τομείς. Το πρώτο της τμήμα (θεωρητικό) περιλαμβάνει μια εισαγωγή στην έννοια της δικτυακής κωδικοποίησης, μια αναφορά στα οφέλη της δικτυακής κωδικοποίησης (βελτίωση ρυθμοαπόδοσης δικτύου, ανθεκτικότητα, προσαρμοστικότητα) και μια συνοπτική περιγραφή των πιο βασικών εφαρμογών της (peer to peer διανομή αρχείων, ασύρματα δίκτυα, αδόμητα (ad-hoc) δίκτυα αισθητήρων). Ακολούθως, υπάρχει μια εκτενής περιγραφή δύο πραγματικών υλοποιήσεων (COPE, MORE) που βασίζονται στη δικτυακή κωδικοποίηση και βρίσκουν χρήση σε ασύρματα δίκτυα. Αυτή περιλαμβάνει τα ακριβή σχεδιασμένα πρωτόκολλα αλλά και διάφορα τεχνικά ζητήματα των υλοποιήσεων. Στη συνέχεια, περνώντας στο πρακτικό μέρος της εργασίας, σχεδιάσθηκε και υλοποιήθηκε εκ μέρους μας ένα πρωτόκολλο που βασίζεται στην δικτυακή κωδικοποίηση και προσεγγίζει σε ορισμένα σημεία την υλοποίηση του COPE. Η υλοποίηση έγινε χρησιμοποιώντας C sockets και αξιολογήθηκε σε ασύρματο δίκτυο. Τα αποτελέσματα των μετρήσεων μας δείχνουν μια χαρακτηριστική βελτίωση στην ρυθμοαπόδοση του δικτύου όταν χρησιμοποιείται δικτυακή κωδικοποίηση σε σύγκριση με την απλή προώθηση μη κωδικοποιημένων πακέτων. Εκτός από την τεκμηρίωση και την ανάλυση του πρωτοκόλλου που σχεδιάσθηκε αλλά και των αντίστοιχων γραφικών παραστάσεων που προέκυψαν από τις μετρήσεις-πειράματα, στο τέλος της εργασίας παρατίθεται και ένας οδηγός «τρεξίματος» του πειράματος μας

Overcoming Untuned Radios in Wireless Networks with Network Coding

Abstract — The drive toward the implementation and massive deployment of wireless sensor networks calls for ultra-low-cost and low-power nodes. While the digital subsystems of the nodes are still riding Moore's Law, there is no such trend regarding the performance of analog components. This work presents a fully integrated architecture of both digital and analog components (including local oscillator) that offers significant reduction in cost, size and power consumption of the overall node. While such a radical architecture cannot offer the reliable tuning of standard designs, it is shown that by using random network coding, a dense network of such nodes can achieve throughput linear in the number of channels available for communication. Moreover, the ratio of the achievable throughput of the untuned network to the throughput of a tuned network with perfect coordination is shown to be close to 1/ e. This work makes use of known results from network coding theory that show that throughput equal to the max-flow in a graph is achievable. However, the challenge here is finding the max-flow of the random graph corresponding to the network

Overcoming untuned radios in wireless networks with network coding

The drive toward the implementation and massive deployment of wireless sensor networks calls for ultra-low-cost and low-power nodes. While the digital subsystems of the nodes are still riding Moore's Law, there is no such trend regarding the performance of analog components. This work presents a fully integrated architecture of both digital and analog components (including local oscillator) that offers significant reduction in cost, size and power consumption of the overall node. While such a radical architecture cannot offer the reliable tuning of standard designs, it is shown that by using random network coding, a dense network of such nodes can achieve throughput linear in the number of channels available for communication. Moreover, the ratio of the achievable throughput of the untuned network to the throughput of a tuned network with perfect coordination is shown to be close to 1/ e. This work makes use of known results from network coding theory that show that throughput equal to the max-flow in a graph is achievable. However, the challenge here is finding the max-flow of the random graph corresponding to the network

Secure location-aware communications in energy-constrained wireless networks

Wireless ad hoc network has enabled a variety of exciting civilian, industrial and military applications over the past few years. Among the many types of wireless ad hoc networks, Wireless Sensor Networks (WSNs) has gained popularity because of the technology development for manufacturing low-cost, low-power, multi-functional motes. Compared with traditional wireless network, location-aware communication is a very common communication pattern and is required by many applications in WSNs. For instance, in the geographical routing protocol, a sensor needs to know its own and its neighbors\u27 locations to forward a packet properly to the next hop. The application-aware communications are vulnerable to many malicious attacks, ranging from passive eavesdropping to active spoofing, jamming, replaying, etc. Although research efforts have been devoted to secure communications in general, the properties of energy-constrained networks pose new technical challenges: First, the communicating nodes in the network are always unattended for long periods without physical maintenance, which makes their energy a premier resource. Second, the wireless devices usually have very limited hardware resources such as memory, computation capacity and communication range. Third, the number of nodes can be potentially of very high magnitude. Therefore, it is infeasible to utilize existing secure algorithms designed for conventional wireless networks, and innovative mechanisms should be designed in a way that can conserve power consumption, use inexpensive hardware and lightweight protocols, and accommodate with the scalability of the network. In this research, we aim at constructing a secure location-aware communication system for energy-constrained wireless network, and we take wireless sensor network as a concrete research scenario. Particularly, we identify three important problems as our research targets: (1) providing correct location estimations for sensors in presence of wormhole attacks and pollution attacks, (2) detecting location anomalies according to the application-specific requirements of the verification accuracy, and (3) preventing information leakage to eavesdroppers when using network coding for multicasting location information. Our contributions of the research are as follows: First, we propose two schemes to improve the availability and accuracy of location information of nodes. Then, we study monitoring and detection techniques and propose three lightweight schemes to detect location anomalies. Finally, we propose two network coding schemes which can effectively prevent information leakage to eavesdroppers. Simulation results demonstrate the effectiveness of our schemes in enhancing security of the system. Compared to previous works, our schemes are more lightweight in terms of hardware cost, computation overhead and communication consumptions, and thus are suitable for energy-constrained wireless networks

Practical security scheme design for resource-constrained wireless networks

The implementation of ubiquitous computing (or pervasive computing) can leverage various types of resource-constrained wireless networks such as wireless sensor networks and wireless personal area networks. These resource-constrained wireless networks are vulnerable to many malicious attacks that often cause leakage, alteration and destruction of critical information due to the insecurity of wireless communication and the tampers of devices. Meanwhile, the constraints of resources, the lack of centralized management, and the demands of mobility of these networks often make traditional security mechanisms inefficient or infeasible. So, the resource-constrained wireless networks pose new challenges for information assurance and call for practical, efficient and effective solutions. In this research, we focus on wireless sensor networks and aim at enhancing confidentiality, authenticity, availability and integrity, for wireless sensor networks. Particularly, we identify three important problems as our research targets: (1) key management for wireless sensor networks (for confidentiality), (2) filtering false data injection and DoS attacks in wireless sensor networks (for authenticity and availability), and (3) secure network coding (for integrity). We investigate a diversity of malicious attacks against wireless sensor networks and design a number of practical schemes for establishing pairwise keys between sensor nodes, filtering false data injection and DoS attacks, and securing network coding against pollution attacks for wireless sensor networks. Our contributions from this research are fourfold: (1) We give a taxonomy of malicious attacks for wireless sensor networks. (2) We design a group-based key management scheme using deployment knowledge for wireless sensor networks to establish pair-wise keys between sensor nodes. (3) We propose an en-route scheme for filtering false data injection and DoS attacks in wireless sensor networks. (4) We present two efficient schemes for securing normal and XOR network coding against pollution attacks. Simulation and experimental results show that our solutions outperform existing ones and are suitable for resource-constrained wireless sensor networks in terms of computation overhead, communication cost, memory requirement, and so on

Network Coding Applications

Network coding is an elegant and novel technique introduced at the turn of the millennium to improve network throughput and performance. It is expected to be a critical technology for networks of the future. This tutorial deals with wireless and content distribution networks, considered to be the most likely applications of network coding, and it also reviews emerging applications of network coding such as network monitoring and management. Multiple unicasts, security, networks with unreliable links, and quantum networks are also addressed. The preceding companion deals with theoretical foundations of network coding