Visible to the public Biblio

Found 173 results

Filters: Keyword is Receivers  [Clear All Filters]
2021-07-08
Chiariotti, Federico, Signori, Alberto, Campagnaro, Filippo, Zorzi, Michele.  2020.  Underwater Jamming Attacks as Incomplete Information Games. IEEE INFOCOM 2020 - IEEE Conference on Computer Communications Workshops (INFOCOM WKSHPS). :1033—1038.
Autonomous Underwater Vehicles (AUVs) have several fundamental civilian and military applications, and Denial of Service (DoS) attacks against their communications are a serious threat. In this work, we analyze such an attack using game theory in an asymmetric scenario, in which the node under attack does not know the position of the jammer that blocks its signals. The jammer has a dual objective, namely, disrupting communications and forcing the legitimate transmitter to spend more energy protecting its own transmissions. Our model shows that, if both nodes act rationally, the transmitter is able to quickly reduce its disadvantage, estimating the location of the jammer and responding optimally to the attack.
Ozmen, Alper, Yildiz, Huseyin Ugur, Tavli, Bulent.  2020.  Impact of Minimizing the Eavesdropping Risks on Lifetime of Underwater Acoustic Sensor Networks. 2020 28th Telecommunications Forum (℡FOR). :1—4.
Underwater Acoustic Sensor Networks (UASNs) are often deployed in hostile environments, and they face many security threats. Moreover, due to the harsh characteristics of the underwater environment, UASNs are vulnerable to malicious attacks. One of the most dangerous security threats is the eavesdropping attack, where an adversary silently collects the information exchanged between the sensor nodes. Although careful assignment of transmission power levels and optimization of data flow paths help alleviate the extent of eavesdropping attacks, the network lifetime can be negatively affected since routing could be established using sub-optimal paths in terms of energy efficiency. In this work, two optimization models are proposed where the first model minimizes the potential eavesdropping risks in the network while the second model maximizes the network lifetime under a certain level of an eavesdropping risk. The results show that network lifetimes obtained when the eavesdropping risks are minimized significantly shorter than the network lifetimes obtained without considering any eavesdropping risks. Furthermore, as the countermeasures against the eavesdropping risks are relaxed, UASN lifetime is shown to be prolonged, significantly.
2021-06-30
He, Kexun, Qin, Kongjian, Wang, Changyuan, Fang, Xiyu.  2020.  Research on Cyber Security Test Method for GNSS of Intelligent Connected Vehicle. 2020 International Conference on Computer Information and Big Data Applications (CIBDA). :200—203.
Intelligent connected vehicle cyber security has attracted widespread attention this year. The safety of GNSS information is related to the safety of cars and has become a key technology. This paper researches the cyber security characteristics of intelligent connected vehicle navigation and positioning by analyzing the signal receiving mode of navigation and positioning on the vehicle terminal. The article expounds the principles of deceiving and interfering cyber security that lead to the safety of GNSS information. This paper studies the key causes of cyber security. Based on key causes, the article constructs a GNSS cyber security test method by combining a navigation signal simulator and an interference signal generator. The results shows that the method can realize the security test of the GNSS information of the vehicle terminal. This method provides a test method for the navigation terminal defense cyber security capability for a vehicle terminal, and fills a gap in the industry for the vehicle terminal information security test.
DelVecchio, Matthew, Flowers, Bryse, Headley, William C..  2020.  Effects of Forward Error Correction on Communications Aware Evasion Attacks. 2020 IEEE 31st Annual International Symposium on Personal, Indoor and Mobile Radio Communications. :1—7.
Recent work has shown the impact of adversarial machine learning on deep neural networks (DNNs) developed for Radio Frequency Machine Learning (RFML) applications. While these attacks have been shown to be successful in disrupting the performance of an eavesdropper, they fail to fully support the primary goal of successful intended communication. To remedy this, a communications-aware attack framework was recently developed that allows for a more effective balance between the opposing goals of evasion and intended communication through the novel use of a DNN to intelligently create the adversarial communication signal. Given the near ubiquitous usage of for-ward error correction (FEC) coding in the majority of deployed systems to correct errors that arise, incorporating FEC in this framework is a natural extension of this prior work and will allow for improved performance in more adverse environments. This work therefore provides contributions to the framework through improved loss functions and design considerations to incorporate inherent knowledge of the usage of FEC codes within the transmitted signal. Performance analysis shows that FEC coding improves the communications aware adversarial attack even if no explicit knowledge of the coding scheme is assumed and allows for improved performance over the prior art in balancing the opposing goals of evasion and intended communications.
2021-05-18
Cho, Sunghwan, Chen, Gaojie, Coon, Justin P..  2020.  Enhancing Security in VLC Systems Through Beamforming. GLOBECOM 2020 - 2020 IEEE Global Communications Conference. :1–6.
This paper proposes a novel zero-forcing (ZF) beamforming strategy that can simultaneously cope with active and passive eavesdroppers (EDs) in visible light communication systems. A related optimization problem is formulated to maximize the signal-to-noise ratio (SNR) of the legitimate user (UE) while suppressing the SNR of active ED to zero and constraining the average SNR of passive EDs. The proposed beamforming directs the transmission along a particular eigenmode related to the null space of the active ED channel and the intensity of the passive ED point process. An inverse free preconditioned Krylov subspace projection method is used to find the eigenmode. The numerical results show that the proposed ZF beamforming scheme yields better performance relative to a traditional ZF beamforming scheme in the sense of increasing the SNR of the UE and reducing the secrecy outage probability.
Mir, Ayesha Waqar, Maqbool, Khawaja Qasim.  2020.  Robust Visible Light Communication in Intelligent Transportation System. 2020 Fourth World Conference on Smart Trends in Systems, Security and Sustainability (WorldS4). :387–391.
Wireless communication in the field of radio frequency (RF) have modernized our society. People experience persistent connection and high-speed data through wireless technologies like Wi-Fi and LTE while browsing the internet. This causes congestion to network; users make it difficult for everyone to access the internet or to communicate reliably on time. The major issues of RF spectrum are intrusion, high latency and it requires an individual transmitter receiver setup in order to function. Dr. Herald Hass came up with an idea of `data through illumination'. Surmounting the drawbacks of RF spectrum, visible light communication (VLC) is more favored technique. In intelligent transportation system (ITS), this evolving technology of VLC has a strong hold in order to connect vehicle-to-infrastructure (V2I) and vehicle-to-vehicle (V2V) links wirelessly. Indoor VLC applications have been studied deeply while the field of vehicular VLC (V-VLC) networking is relatively a less researched domain because it has greater level of intrusion and additive ambient light noise is higher in outdoor VLC. Other factors due to which the implementation of VLC faces a lot of hurdles are mostly related to environment such as dust, haze, snow, sunlight, rain, fog, smog and atmospheric disturbances. In this paper, we executed a thorough channel modelling in order to study the effects of clear weather, fog, snow and rain quantitatively with respect to different wavelengths in consideration for an ITS. This makes ITS more robust in nature. The parameters under consideration will be signal-to-noise ratio (SNR), bit error rate (BER) and optical power received (OPR) for different LED wavelengths.
2021-05-13
Madanchi, Mehdi, Abolhassani, Bahman.  2020.  Authentication and Key Agreement Based Binary Tree for D2D Group Communication. 2020 28th Iranian Conference on Electrical Engineering (ICEE). :1—5.

Emerging device-to-device (D2D) communication in 5th generation (5G) mobile communication networks and internet of things (loTs) provides many benefits in improving network capabilities such as energy consumption, communication delay and spectrum efficiency. D2D group communication has the potential for improving group-based services including group games and group discussions. Providing security in D2D group communication is the main challenge to make their wide usage possible. Nevertheless, the issue of security and privacy of D2D group communication has been less addressed in recent research work. In this paper, we propose an authentication and key agreement tree group-based (AKATGB) protocol to realize a secure and anonymous D2D group communication. In our protocol, a group of D2D users are first organized in a tree structure, authenticating each other without disclosing their identities and without any privacy violation. Then, D2D users negotiate to set a common group key for establishing a secure communication among themselves. Security analysis and performance evaluation of the proposed protocol show that it is effective and secure.

2021-04-27
Sidhu, H. J. Singh, Khanna, M. S..  2020.  Cloud's Transformative Involvement in Managing BIG-DATA ANALYTICS For Securing Data in Transit, Storage And Use: A Study. 2020 Sixth International Conference on Parallel, Distributed and Grid Computing (PDGC). :297—302.

with the advent of Cloud Computing a new era of computing has come into existence. No doubt, there are numerous advantages associated with the Cloud Computing but, there is other side of the picture too. The challenges associated with it need a more promising reply as far as the security of data that is stored, in process and in transit is concerned. This paper put forth a cloud computing model that tries to answer the data security queries; we are talking about, in terms of the four cryptographic techniques namely Homomorphic Encryption (HE), Verifiable Computation (VC), Secure Multi-Party Computation (SMPC), Functional Encryption (FE). This paper takes into account the various cryptographic techniques to undertake cloud computing security issues. It also surveys these important (existing) cryptographic tools/techniques through a proposed Cloud computation model that can be used for Big Data applications. Further, these cryptographic tools are also taken into account in terms of CIA triad. Then, these tools/techniques are analyzed by comparing them on the basis of certain parameters of concern.

Damis, H. A., Shehada, D., Fachkha, C., Gawanmeh, A., Al-Karaki, J. N..  2020.  A Microservices Architecture for ADS-B Data Security Using Blockchain. 2020 3rd International Conference on Signal Processing and Information Security (ICSPIS). :1—4.

The use of Automatic Dependent Surveillance - Broadcast (ADS-B) for aircraft tracking and flight management operations is widely used today. However, ADS-B is prone to several cyber-security threats due to the lack of data authentication and encryption. Recently, Blockchain has emerged as new paradigm that can provide promising solutions in decentralized systems. Furthermore, software containers and Microservices facilitate the scaling of Blockchain implementations within cloud computing environment. When fused together, these technologies could help improve Air Traffic Control (ATC) processing of ADS-B data. In this paper, a Blockchain implementation within a Microservices framework for ADS-B data verification is proposed. The aim of this work is to enable data feeds coming from third-party receivers to be processed and correlated with that of the ATC ground station receivers. The proposed framework could mitigate ADS- B security issues of message spoofing and anomalous traffic data. and hence minimize the cost of ATC infrastructure by throughout third-party support.

Kuhn, C., Beck, M., Strufe, T..  2020.  Breaking and (Partially) Fixing Provably Secure Onion Routing. 2020 IEEE Symposium on Security and Privacy (SP). :168–185.
After several years of research on onion routing, Camenisch and Lysyanskaya, in an attempt at rigorous analysis, defined an ideal functionality in the universal composability model, together with properties that protocols have to meet to achieve provable security. A whole family of systems based their security proofs on this work. However, analyzing HORNET and Sphinx, two instances from this family, we show that this proof strategy is broken. We discover a previously unknown vulnerability that breaks anonymity completely, and explain a known one. Both should not exist if privacy is proven correctly.In this work, we analyze and fix the proof strategy used for this family of systems. After proving the efficacy of the ideal functionality, we show how the original properties are flawed and suggest improved, effective properties in their place. Finally, we discover another common mistake in the proofs. We demonstrate how to avoid it by showing our improved properties for one protocol, thus partially fixing the family of provably secure onion routing protocols.
2021-04-09
Cui, H., Liu, C., Hong, X., Wu, J., Sun, D..  2020.  An Improved BICM-ID Receiver for the Time-Varying Underwater Acoustic Communications with DDPSK Modulation. 2020 IEEE International Conference on Signal Processing, Communications and Computing (ICSPCC). :1—4.
Double differential phase shift keying(DDPSK) modulation is an efficient method to compensate the Doppler shifts, whereas the phase noise will be amplified which results in the signal-to-noise ratio (SNR) loss. In this paper, we propose a novel receiver architecture for underwater acoustic DSSS communications with Doppler shifts. The proposed method adopts not only the DDPSK modulation to compensate the Doppler shifts, but also the improved bit-interleaved coded modulation with iterative decoding (BICM-ID) algorithm for DDPSK to recover the SNR loss. The improved DDPSK demodulator adopts the multi-symbol estimation to track the channel variation, and an extended trellis diagram is constructed for DDPSK demodulator. Theoretical simulation shows that our system can obtain around 10.2 dB gain over the uncoded performance, and 7.4 dB gain over the hard-decision decoding performance. Besides, the experiment conducted in the Songhua Lake also shows that the proposed receiver can achieve lower BER performance when Doppler shifts exists.
Bhattacharya, M. P., Zavarsky, P., Butakov, S..  2020.  Enhancing the Security and Privacy of Self-Sovereign Identities on Hyperledger Indy Blockchain. 2020 International Symposium on Networks, Computers and Communications (ISNCC). :1—7.
Self-sovereign identities provide user autonomy and immutability to individual identities and full control to their identity owners. The immutability and control are possible by implementing identities in a decentralized manner on blockchains that are specially designed for identity operations such as Hyperledger Indy. As with any type of identity, self-sovereign identities too deal with Personally Identifiable Information (PII) of the identity holders and comes with the usual risks of privacy and security. This study examined certain scenarios of personal data disclosure via credential exchanges between such identities and risks of man-in-the-middle attacks in the blockchain based identity system Hyperledger Indy. On the basis of the findings, the paper proposes the following enhancements: 1) A novel attribute sensitivity score model for self-sovereign identity agents to ascertain the sensitivity of attributes shared in credential exchanges 2) A method of mitigating man-in-the-middle attacks between peer self-sovereign identities and 3) A novel quantitative model for determining a credential issuer's reputation based on the number of issued credentials in a window period, which is then utilized to calculate an overall confidence level score for the issuer.
2021-04-08
Tyagi, H., Vardy, A..  2015.  Universal Hashing for Information-Theoretic Security. Proceedings of the IEEE. 103:1781–1795.
The information-theoretic approach to security entails harnessing the correlated randomness available in nature to establish security. It uses tools from information theory and coding and yields provable security, even against an adversary with unbounded computational power. However, the feasibility of this approach in practice depends on the development of efficiently implementable schemes. In this paper, we review a special class of practical schemes for information-theoretic security that are based on 2-universal hash families. Specific cases of secret key agreement and wiretap coding are considered, and general themes are identified. The scheme presented for wiretap coding is modular and can be implemented easily by including an extra preprocessing layer over the existing transmission codes.
Chrysikos, T., Dagiuklas, T., Kotsopoulos, S..  2010.  Wireless Information-Theoretic Security for moving users in autonomic networks. 2010 IFIP Wireless Days. :1–5.
This paper studies Wireless Information-Theoretic Security for low-speed mobility in autonomic networks. More specifically, the impact of user movement on the Probability of Non-Zero Secrecy Capacity and Outage Secrecy Capacity for different channel conditions has been investigated. This is accomplished by establishing a link between different user locations and the boundaries of information-theoretic secure communication. Human mobility scenarios are considered, and its impact on physical layer security is examined, considering quasi-static Rayleigh channels for the fading phenomena. Simulation results have shown that the Secrecy Capacity depends on the relative distance of legitimate and illegitimate (eavesdropper) users in reference to the given transmitter.
Wu, X., Yang, Z., Ling, C., Xia, X..  2016.  Artificial-Noise-Aided Message Authentication Codes With Information-Theoretic Security. IEEE Transactions on Information Forensics and Security. 11:1278–1290.
In the past, two main approaches for the purpose of authentication, including information-theoretic authentication codes and complexity-theoretic message authentication codes (MACs), were almost independently developed. In this paper, we consider to construct new MACs, which are both computationally secure and information-theoretically secure. Essentially, we propose a new cryptographic primitive, namely, artificial-noise-aided MACs (ANA-MACs), where artificial noise is used to interfere with the complexity-theoretic MACs and quantization is further employed to facilitate packet-based transmission. With a channel coding formulation of key recovery in the MACs, the generation of standard authentication tags can be seen as an encoding process for the ensemble of codes, where the shared key between Alice and Bob is considered as the input and the message is used to specify a code from the ensemble of codes. Then, we show that artificial noise in ANA-MACs can be well employed to resist the key recovery attack even if the opponent has an unlimited computing power. Finally, a pragmatic approach for the analysis of ANA-MACs is provided, and we show how to balance the three performance metrics, including the completeness error, the false acceptance probability, and the conditional equivocation about the key. The analysis can be well applied to a class of ANA-MACs, where MACs with Rijndael cipher are employed.
Ekşim, A., Demirci, T..  2020.  Ultimate Secrecy in Cooperative and Multi-hop Wireless Communications. 2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science. :1–4.
In this work, communication secrecy in cooperative and multi-hop wireless communications for various radio frequencies are examined. Attenuation lines and ranges of both detection and ultimate secrecy regions were calculated for cooperative communication channel and multi-hop channel with various number of hops. From results, frequency ranges with the highest potential to apply bandwidth saving method known as frequency reuse were determined and compared to point-to-point channel. Frequencies with the highest attenuation were derived and their ranges of both detection and ultimate secrecy are calculated. Point-to-point, cooperative and multi-hop channels were compared in terms of ultimate secrecy ranges. Multi-hop channel measurements were made with different number of hops and the relation between the number of hops and communication security is examined. Ultimate secrecy ranges were calculated up to 1 Terahertz and found to be less than 13 meters between 550-565 GHz frequency range. Therefore, for short-range wireless communication systems such as indoor and in-device communication systems (board-to-board or chip-to-chip communications), it is shown that various bands in the Terahertz band can be used to reuse the same frequency in different locations to obtain high security and high bandwidth.
2021-03-15
Chai, L., Ren, P., Du, Q..  2020.  A Secure Transmission Scheme Based on Efficient Transmission Fountain Code. 2020 IEEE/CIC International Conference on Communications in China (ICCC). :600–604.

Improving the security of data transmission in wireless channels is a key and challenging problem in wireless communication. This paper presents a data security transmission scheme based on high efficiency fountain code. If the legitimate receiver can decode all the original files before the eavesdropper, it can guarantee the safe transmission of the data, so we use the efficient coding scheme of the fountain code to ensure the efficient transmission of the data, and add the feedback mechanism to the transmission of the fountain code so that the coding scheme can be updated dynamically according to the decoding situation of the legitimate receiver. Simulation results show that the scheme has high security and transmitter transmission efficiency in the presence of eavesdropping scenarios.

2021-03-09
Sibahee, M. A. A., Lu, S., Abduljabbar, Z. A., Liu, E. X., Ran, Y., Al-ashoor, A. A. J., Hussain, M. A., Hussien, Z. A..  2020.  Promising Bio-Authentication Scheme to Protect Documents for E2E S2S in IoT-Cloud. 2020 IEEE International Conference on Signal Processing, Communications and Computing (ICSPCC). :1—6.

Document integrity and origin for E2E S2S in IoTcloud have recently received considerable attention because of their importance in the real-world fields. Maintaining integrity could protect decisions made based on these message/image documents. Authentication and integrity solutions have been conducted to recognise or protect any modification in the exchange of documents between E2E S2S (smart-to-smart). However, none of the proposed schemes appear to be sufficiently designed as a secure scheme to prevent known attacks or applicable to smart devices. We propose a robust scheme that aims to protect the integrity of documents for each users session by integrating HMAC-SHA-256, handwritten feature extraction using a local binary pattern, one-time random pixel sequence based on RC4 to randomly hide authentication codes using LSB. The proposed scheme can provide users with one-time bio-key, robust message anonymity and a disappearing authentication code that does not draw the attention of eavesdroppers. Thus, the scheme improves the data integrity for a users messages/image documents, phase key agreement, bio-key management and a one-time message/image document code for each users session. The concept of stego-anonymity is also introduced to provide additional security to cover a hashed value. Finally, security analysis and experimental results demonstrate and prove the invulnerability and efficiency of the proposed scheme.

Tikhomirov, S., Moreno-Sanchez, P., Maffei, M..  2020.  A Quantitative Analysis of Security, Anonymity and Scalability for the Lightning Network. 2020 IEEE European Symposium on Security and Privacy Workshops (EuroS PW). :387—396.

Payment channel networks have been introduced to mitigate the scalability issues inherent to permissionless decentralized cryptocurrencies such as Bitcoin. Launched in 2018, the Lightning Network (LN) has been gaining popularity and consists today of more than 5000 nodes and 35000 payment channels that jointly hold 965 bitcoins (9.2M USD as of June 2020). This adoption has motivated research from both academia and industryPayment channels suffer from security vulnerabilities, such as the wormhole attack [39], anonymity issues [38], and scalability limitations related to the upper bound on the number of concurrent payments per channel [28], which have been pointed out by the scientific community but never quantitatively analyzedIn this work, we first analyze the proneness of the LN to the wormhole attack and attacks against anonymity. We observe that an adversary needs to control only 2% of nodes to learn sensitive payment information (e.g., sender, receiver, and amount) or to carry out the wormhole attack. Second, we study the management of concurrent payments in the LN and quantify its negative effect on scalability. We observe that for micropayments, the forwarding capability of up to 50% of channels is restricted to a value smaller than the channel capacity. This phenomenon hinders scalability and opens the door for denial-of-service attacks: we estimate that a network-wide DoS attack costs within 1.6M USD, while isolating the biggest community costs only 238k USDOur findings should prompt the LN community to consider the issues studied in this work when educating users about path selection algorithms, as well as to adopt multi-hop payment protocols that provide stronger security, privacy and scalability guarantees.

2021-03-04
Cao, L., Wan, Z..  2020.  Anonymous scheme for blockchain atomic swap based on zero-knowledge proof. 2020 IEEE International Conference on Artificial Intelligence and Computer Applications (ICAICA). :371—374.
The blockchain's cross-chain atomic exchange uses smart contracts to replace trusted third parties, but atomic exchange cannot guarantee the anonymity of transactions, and it will inevitably increase the risk of privacy leakage. Therefore, this paper proposes an atom based on zero-knowledge proof. Improved methods of exchange to ensure the privacy of both parties in a transaction. The anonymous improvement scheme in this article uses the UTXO unconsumed model to add a new anonymous list in the blockchain. When sending assets to smart contracts, zero-knowledge proof is used to provide self-certification of ownership of the asset, and then the transaction is broken down. Only the hash value of the transaction is sent to the node, and the discarded list is used to verify the validity of the transaction, which achieves the effect of storing assets anonymously in the smart contract. At the same time, a smart contract is added when the two parties in the transaction communicate to exchange the contract address of the newly set smart contract between the two parties in the transaction. This can prevent the smart contract address information from being stolen when the two parties in the transaction communicate directly.
2021-02-23
Kabatiansky, G., Egorova, E..  2020.  Adversarial multiple access channels and a new model of multimedia fingerprinting coding. 2020 IEEE Conference on Communications and Network Security (CNS). :1—5.

We consider different models of malicious multiple access channels, especially for binary adder channel and for A-channel, and show how they can be used for the reformulation of digital fingerprinting coding problems. In particular, we propose a new model of multimedia fingerprinting coding. In the new model, not only zeroes and plus/minus ones but arbitrary coefficients of linear combinations of noise-like signals for forming watermarks (digital fingerprints) can be used. This modification allows dramatically increase the possible number of users with the property that if t or less malicious users create a forge digital fingerprint then a dealer of the system can find all of them with zero-error probability. We show how arisen problems are related to the compressed sensing problem.

2021-02-15
Gladwin, S. J., Gowthami, P. Lakshmi.  2020.  Combined Cryptography and Steganography for Enhanced Security in Suboptimal Images. 2020 International Conference on Artificial Intelligence and Signal Processing (AISP). :1–5.
Technology has developed to a very great extent, and the use of smart systems has introduced an increasing threat to data security and privacy. Most of the applications are built-in unsecured operating systems, and so there is a growing threat to information cloning, forging tampering counterfeiting, etc.. This will lead to an un-compensatory loss for end-users particularly in banking applications and personal data in social media. A robust and effective algorithm based on elliptic curve cryptography combined with Hill cipher has been proposed to mitigate such threats and increase information security. In this method, ciphertext and DCT coefficients of an image, embedded into the base image based on LSB watermarking. The ciphertext is generated based on the Hill Cipher algorithm. Hill Cipher can, however, be easily broken and has weak security and to add complexity, Elliptic curve cryptography (ECC), is combined with Hill cipher. Based on the ECC algorithm, the key is produced, and this key is employed to generate ciphertext through the Hill cipher algorithm. This combination of both steganography and cryptography results in increased authority and ownership of the data for sub-optimal media applications. It is hard to extract the hidden data and the image without the proper key. The performance for hiding text and image into an image data have been analyzed for sub-optimal multimedia applications.
2021-02-10
Huang, H., Wang, X., Jiang, Y., Singh, A. K., Yang, M., Huang, L..  2020.  On Countermeasures Against the Thermal Covert Channel Attacks Targeting Many-core Systems. 2020 57th ACM/IEEE Design Automation Conference (DAC). :1—6.
Although it has been demonstrated in multiple studies that serious data leaks could occur to many-core systems thanks to the existence of the thermal covert channels (TCC), little has been done to produce effective countermeasures that are necessary to fight against such TCC attacks. In this paper, we propose a three-step countermeasure to address this critical defense issue. Specifically, the countermeasure includes detection based on signal frequency scanning, positioning affected cores, and blocking based on Dynamic Voltage Frequency Scaling (DVFS) technique. Our experiments have confirmed that on average 98% of the TCC attacks can be detected, and with the proposed defense, the bit error rate of a TCC attack can soar to 92%, literally shutting down the attack in practical terms. The performance penalty caused by the inclusion of the proposed countermeasures is only 3% for an 8×8 system.
Kim, S. W., Ta, H. Q..  2020.  Covert Communication by Exploiting Node Multiplicity and Channel Variations. ICC 2020 - 2020 IEEE International Conference on Communications (ICC). :1—6.
We present a covert (low probability of detection) communication scheme that exploits the node multiplicity and channel variations in wireless broadcast networks. The transmitter hides the covert (private) message by superimposing it onto a non-covert (public) message such that the total transmission power remains the same whether or not the covert message is transmitted. It makes the detection of the covert message impossible unless the non-covert message is decoded. We exploit the multiplicity of non-covert messages (users) to provide a degree of freedom in choosing the non-covert message such that the total detection error probability (sum of the probability of false alarm and missed detection) is maximized. We also exploit the channel variation to minimize the throughput loss on the non-covert message by sending the covert message only when the transmission rate of the non-covert message is low. We show that the total detection error probability converges fast to 1 as the number of non-covert users increases and that the total detection error probability increases as the transmit power increases, without requiring a pre-shared secret among the nodes.
Hou, N., Zheng, Y..  2020.  CloakLoRa: A Covert Channel over LoRa PHY. 2020 IEEE 28th International Conference on Network Protocols (ICNP). :1—11.
This paper describes our design and implementation of a covert channel over LoRa physical layer (PHY). LoRa adopts a unique modulation scheme (chirp spread spectrum (CSS)) to enable long range communication at low-power consumption. CSS uses the initial frequencies of LoRa chirps to differentiate LoRa symbols, while simply ignoring other RF parameters (e.g., amplitude and phase). Our study reveals that the LoRa physical layer leaves sufficient room to build a covert channel by embedding covert information with a modulation scheme orthogonal to CSS. To demonstrate the feasibility of building a covert channel, we implement CloakLoRa. CloakLoRa embeds covert information into a regular LoRa packet by modulating the amplitudes of LoRa chirps while keeping the frequency intact. As amplitude modulation is orthogonal to CSS, a regular LoRa node receives the LoRa packet as if no secret information is embedded into the packet. Such an embedding method is transparent to all security mechanisms at upper layers in current LoRaWAN. As such, an attacker can create an amplitude modulated covert channel over LoRa without being detected by current LoRaWAN security mechanism. We conduct comprehensive evaluations with COTS LoRa nodes and receive-only software defined radios and experiment results show that CloakLoRa can send covert information over 250m.