My course on WSN and VANET Security
This course is included in the Doctoral Program in Information and Communication Technology at the University of L'Aquila. It deals with the security management principles - according to ISO 31000 Risk Management - and the applicable techniques to Wireless Sensor Networks (WSN) and Vehicular Ad hoc NETworks
(VANET), special classes of wireless ad hoc networks.
Wireless sensor networks (Wireless Sensor Network, WSN), wireless inter-vehicular and intra-vehicular networks (Vehicular Ad-hoc Networks, VANET) are instances of wireless ad-hoc networks.
Wireless ad-hoc networks can be rightly considered as enablers for Operation Technologies (OT): nowadays we are observing a process of convergence with the extension of classical IT cyber risks also to OT domain to be managed in accordance with the NIS and the future NIS2 by OSE (Operatori di Servizi Essenziali).
The seminar objective is introducing WSN and VANET security issues, challenges and risk countermeasures as a simple but concrete guide line to manage a Cyber Security Management Process compliant to ISO and NIST standards.
According to the ISO 31000, we can refer to "security management process" as a 4-steps iterated process starting from cyber risk identification, evaluation and quantification, mitigation and continuous monitoring until a residual risk assumed acceptable has been reached: in other words "security application" corresponds to a rebalancing process where security vulnerabilities get reduced when the proper countermeasures (in this case specific security functions) are applied. The "Required Security Level" (RSL) for the system can be determined from the analysis of its security vulnerabilities, hence RSL evaluation strongly depends on the evaluation / quantification of cyber vulnerabilities (CRQ). Techniques for CRQ for an IT-OT integrated scenario are described. On the other side, the security performance offered by a security function (that can quantitatively estimated) determines the "Offered Security Level" (or "Expected Security Level"). The condition for the "security application" to a specific network function is given by its "Required Security Level" balanced by the "Offered Security Level" of some security function.
ISO 31000 defines passive and active countermeasures: from a security point of view, passive functions typically include cryptographic techniques, hashing, message authentication codes, secure routing, while active functions include estimation techniques of system behavior or misbehavior able to detect cyber attacks (intrusion / attack detection and classification) through the issue of an alarm. ISO 31000 principles inspire the operative procedures for the specific technical standards in engineering domains: e.g. ISO 27000 family for the ICT domain, ISO 26262 and the future ISO 21434 for the automotive domain.
Mathematical methods to compute the security performance of a cryptographic technique are set by the "information theoretic security" - or information theory applied to security - introduced by C. E. Shannon in 1949 with its masterwork "Communication Theory of Secrecy Systems".
Passive security functions for WSNs and VANETs are still based on the ordinary cryptographic mechanisms (symmetric, asymmetric, hybrid schemes) but the technical constrains of the microprocessors embedded into WSN and VANET nodes push to innovative and raffinate techniques such as elliptic curve cryptography (ECC) and identity-based cryptography (useful for privacy preserving in VANETs). Active security functions are based on behavior estimators and classifiers derived from the theory of Discrete Event Dynamic Systems and Machine Learning algorithms.
The course introduces specific set of security techniques applicable to WSN and VANET systems that usually result in hybrid approaches trying to optimize benefits of the ordinary schemes with network constrains.
The course reports the passive and active security functions from literature and those that have been introduced and developed at Univaq labs during last years currently employed in several projects as SEAMLESS, EMERGE, SHINE-ON: TAKS (Topology Authenticated Key Scheme) and its ECC-based version ECTAKS (Elliptic Curve Topology Authenticated Key Scheme) as well as the intrusion detection system WIDS (WPM-based Intrusion Detection System) and MVET (Mean-Variance Evaluation Technique).
In this sense the family of cryptographic schemes
denoted as TAKS (Topology Authenticated Key Scheme) and the intrusion
detection system denoted as WIDS (WPM-based Intrusion Detection System) are introduced. TAKS (and its ECC-based version denoted as ECTAKS) and
WIDS techniques have been designed at DEWS within the WINSOME Project (Wireless
Sensor Network Secure System for Structural
Integrity Monitoring and Alerting). WINSOME is an experimental platform where security functions TAKS and WIDS have been developed and tested on various WSN technologies
by students from M. S. and Ph. D. courses to build demonstrators ready for customizations in other projects. As an example TAKS and WIDS have been successfully implemented over a clustered IRIS-based WSN in PNRM SEAMLESS Project and currently into operation to collect and monitor parameters related to the agricoltural sector in ECSEL AFarCloud Project.
Slides from A.A. 2023/24 course:
Elements of a wireless network, Wireless Network Taxonomy: Adhoc Networks (ANET), Mobile ANET (MANET), Vehicular ANET (VANET), Wireless Sensor Network (WSN). Course Program. Course Schedule.
Part I: Generalities on WSN and VANET Security
I.1 WSN Architectures and Application Scenarios. Wireless Sensor Network (WSN): Applications, Design Issues, Reference WSN Architecture. IEEE 802.15.4, ZigBee, TinyOS.
I.2 VANET Architectures and Application Scenarios. Definition of VANET, VANET vs. MANET, VANET Applications. Inter-Vehicular Communications Systems: WAVE project, 3GPP vs. ETSI standard vision. Intra-Vehicular Communications Systems.
I.3 Security Management. The framework of Security Management: from Risk to Security Management. Security Management Process, Models and Techniques for Cyber Risk Evaluation: FTA / ETA / CVSS. Reference Security Model: Security metrics, Timing constraints, Required Security Level vs. Offered Security Level. Guide lines to manage a Cyber Security Management Process.
I.4 Cyber Attackers and Attacks. Classification of cyber attackers and attacks: cyber attacks against WSN, VANET and Intra-Vehicle Communications. Classification of the Security Functions: Passive / Active Security Functions.
Part II: Techniques for WSN and VANET Security
II.1 Passive Security Functions. Mathematical background: Kerckhoffs' principle. The Shannon's lessons. Hints on modular arithmetics, Galois fields and extensions, prime numbers, pseudo-random numbers, elliptic curve (EC) algebra, discrete logarithm problem and its EC version, pairings on elliptic curves, zero knowledge proof. Techniques: Shannon's S-box and P-box, AES, block ciphers and operation modes (CBC, CTR), hash functions, message authentication codes (CBC-MAC, CCM, CMAC), digital signatures. Key establishment protocols: symmetric / asymmetric / hybrid KEP, ID based KEP. Authentication of the public key. Key Management Protocols: TinySEC, TinyECC, TinyIBE. Passive security techniques for IEEE 802.15.4 MAC, Routing, ZigBee.
II.2 Active Security Functions. Mathematical background: dynamic systems, discrete event dynamical systems (DEDS), the Intrusion Detection Problem: DEDS modeling using Petri Nets (PN), mapping PN into a finite automaton (FA), identification of observables and hidden states, state sequence estimation, behavior classifier, information theoretic model of an Intrusion Detection System. Techniques: Machine Learning: Supervised, Unsupervised and Semi-Supervised Learning. Classification Techniques. Intrusion Detection System Reference Model: Anomaly-based vs. Signature-based. Audit data. Representation Model and Classification Model.
II.3 Security Techniques made in Univaq. TAKS/ECTAKS: TAKS / ECTAKS Scheme, TAKSx driving ideas & main features, TAKS Definition, TAK Equations, Geometric Interpretation of TAK, Authenticated Network Topology. ECC-based TAKS (ECTAKS), ECTAKS vs. ECDHE, pwECTAKS, cwECTAKS. ECTAKS Schemes for Encryption / Decryption and Sender Signature. Intro to ECTAKS Security Proof. TAKSx release chronology. WIDS/MVET: WIDS driving ideas & main features, reference architecture, technique, security analysis. WIDS for IEEE 802.15.4 systems. MVET driving ideas & main features, reference architecture, technique, performance analysis.
II.4 VANET Security and Privacy. V2X Communications Security: IEEE 1609.2 architecture, analysis. Privacy preserving solutions. Intra-Vehicle Communications Security: Vulnerabilities and Security Measures.