Biblio
Distributed Denial of Service (DDoS) attacks serve to diminish the ability of the network to perform its intended function over time. The paper presents the design, implementation and analysis of a protocol based upon a technique for address agility called DDoS Resistant Multicast (DRM). After describing the our architecture and implementation we show an analysis that quantifies the overhead on network performance. We then present the Simple Agile RPL multiCAST (SARCAST), an Internet-of-Things routing protocol for DDoS protection. We have implemented and evaluated SARCAST in a working IoT operating system and testbed. Our results show that SARCAST provides very high levels of protection against DDoS attacks with virtually no impact on overall performance.
High accurate time synchronization is very important for many applications and industrial environments. In a computer network, synchronization of time for connected devices is provided by the Precision Time Protocol (PTP), which in principal allows for device time synchronization down to microsecond level. However, PTP and network infrastructures are vulnerable to cyber-attacks, which can de-synchronize an entire network, leading to potentially devastating consequences. This paper will focus on the issue of internal attacks on time synchronization networks and discuss how counter-measures based on public key infrastructures, trusted platform modules, network intrusion detection systems and time synchronization supervisors can be adopted to defeat or at least detect such internal attacks.
Mobile applications have grown from knowing basic personal information to knowing intimate details of consumer's lives. The explosion of knowledge that applications contain and share can be contributed to many factors. Mobile devices are equipped with advanced sensors including GPS and cameras, while storing large amounts of personal information including photos and contacts. With millions of applications available to install, personal data is at constant risk of being misused. While mobile operating systems provide basic security and privacy controls, they are insufficient, leaving the consumer unaware of how applications are using permissions that were granted. In this paper, we propose a solution that aims to provide consumers awareness of applications misusing data and policies that can protect their data. From this investigation we present SPEProxy. SPEProxy utilizes a knowledge based approach to provide consumer's an ability to understand how applications are using permissions beyond their stated intent. Additionally, SPEProxy provides an awareness of fine grained policies that would allow the user to protect their data. SPEProxy is device and mobile operating system agnostic, meaning it does not require a specific device or operating system nor modification to the operating system or applications. This approach allows consumers to utilize the solution without requiring a high degree of technical expertise. We evaluated SPEProxy across 817 of the most popular applications in the iOS App Store and Google Play. In our evaluation, SPEProxy was highly effective across 86.55% applications where several well known applications exhibited misusing granted permissions.
Communication networks can be the targets of organized and distributed attacks such as flooding-type DDOS attack in which malicious users aim to cripple a network server or a network domain. For the attack to have a major effect on the network, malicious users must act in a coordinated and time correlated manner. For instance, the members of the flooding attack increase their message transmission rates rapidly but also synchronously. Even though detection and prevention of the flooding attacks are well studied at network and transport layers, the emergence and wide deployment of new systems such as VoIP (Voice over IP) have turned flooding attacks at the session layer into a new defense challenge. In this study a structured sparsity based group anomaly detection system is proposed that not only can detect synchronized attacks, but also identify the malicious groups from normal users by jointly estimating their members, structure, starting and end points. Although we mainly focus on security on SIP (Session Initiation Protocol) servers/proxies which are widely used for signaling in VoIP systems, the proposed scheme can be easily adapted for any type of communication network system at any layer.
After a brief introduction on optical chaotic cryptography, we compare the standard short cavity, close-loop, two-laser and three-laser schemes for secure transmission, showing that both are suitable for secure data exchange, the three-laser scheme offering a slightly better level of privacy, due to its symmetrical topology.
Multivariate public key cryptosystem acts as a signature system rather than encryption system due to the minus mode used in system. A multivariate encryption system with determinate equations in central map and chaotic shell protection for central map and affine map is proposed in this paper. The outputs of two-dimension chaotic system are discretized on a finite field to disturb the central map and affine map in multivariate cryptosystem. The determined equations meet the shortage of indeterminate equations in minus mode and make the general attack methods are out of tenable condition. The analysis shows the proposed multivariate symmetric encryption system based on chaotic shell is able to resist general attacks.
Radio frequency identification (RFID) is one of the key technologies of Internet of Things, which have many security issues in an open environment. In order to solve the communication problem between RFID tags and readers, security protocols has been improved constantly as the first choice. But the form of attack is also changing constantly with the development of technology. In this paper we classify the security protocols and introduce some problems in the recent security protocols.
Multi- and many-core systems are increasingly prevalent in embedded systems. Additionally, isolation requirements between different partitions and criticalities are gaining in importance. This difficult combination is not well addressed by current software systems. Parallel systems require consistency guarantees on shared data-structures often provided by locks that use predictable resource sharing protocols. However, as the number of cores increase, even a single shared cache-line (e.g. for the lock) can cause significant interference. In this paper, we present a clean-slate design of the SPeCK kernel, the next generation of our COMPOSITE OS, that attempts to provide a strong version of scalable predictability - where predictability bounds made on a single core, remain constant with an increase in cores. Results show that, despite using a non-preemptive kernel, it has strong scalable predictability, low average-case overheads, and demonstrates better response-times than a state-of-the-art preemptive system.
We build upon the clean-slate, holistic approach to the design of secure protocols for wireless ad-hoc networks proposed in part one. We consider the case when the nodes are not synchronized, but instead have local clocks that are relatively affine. In addition, the network is open in that nodes can enter at arbitrary times. To account for this new behavior, we make substantial revisions to the protocol in part one. We define a game between protocols for open, unsynchronized nodes and the strategies of adversarial nodes. We show that the same guarantees in part one also apply in this game: the protocol not only achieves the max-min utility, but the min-max utility as well. That is, there is a saddle point in the game, and furthermore, the adversarial nodes are effectively limited to either jamming or conforming with the protocol.
Side Channel Attacks (SCA) using power measurements are a known method of breaking cryptographic algorithms such as AES. Published research into attacks on AES frequently target only AES-128, and often target only the core Electronic Code-Book (ECB) algorithm, without discussing surrounding issues such as triggering, along with breaking the initialization vector. This paper demonstrates a complete attack on a secure bootloader, where the firmware files have been encrypted with AES-256-CBC. A classic Correlation Power Analysis (CPA) attack is performed on AES-256 to recover the complete 32-byte key, and a CPA attack is also used to attempt recovery of the initialization vector (IV).
Selective encryption designates a technique that aims at scrambling a message content while preserving its syntax. Such an approach allows encryption to be transparent towards middle-box and/or end user devices, and to easily fit within existing pipelines. In this paper, we propose to apply this property to a real-time diffusion scenario - or broadcast - over a RTP session. The main challenge of such problematic is the preservation of the synchronization between encryption and decryption. Our solution is based on the Advanced Encryption Standard in counter mode which has been modified to fit our auto-synchronization requirement. Setting up the proposed synchronization scheme does not induce any latency, and requires no additional bandwidth in the RTP session (no additional information is sent). Moreover, its parallel structure allows to start decryption on any given frame of the video while leaving a lot of room for further optimization purposes.
Clock and data recovery (CDR) systems are the first logic blocks in serial data receivers and the latter's performance depends on the CDR. In this paper, a 100 Gbit/s CDR designed in 130 nm BiCMOS SiGe is presented. The CDR uses an injection locked oscillator (ILO) which delivers the 100 GHz clock. The inherent phase shift between the recovered clock and the incoming data is compensated by a feedback loop which performs phase and frequency tracking. Furthermore, a windowed phase comparator has been used, first to lower the classical number of gates, in order to prevent any delay skews between the different phase detector blocks, then to decrease the phase comparator operating frequency, and furthermore to extend the ability to track zero bit patterns The measurements results demonstrate a 100 GHz clock signal extracted from 50 Gb/s input data, with a phase noise as low as 98 dBc/Hz at 100 kHz offset from the carrier frequency. The rms jitter of the 25 GHz recovered data is only 1.2 ps. The power consumption is 1.4 W under 2.3 V power supply.
As the interconnect delay is becoming a larger fraction of the clock cycle time, the conventional global stalling mechanism, which is used to correct error in general synchronous circuits, would be no longer feasible because of the expensive timing cost for the stalling signal to travel across the circuit. In this paper, we propose recovery-based resilient latency-insensitive systems (RLISs) that efficiently integrate error-recovery techniques with latency-insensitive design to replace the global stalling. We first demonstrate a baseline RLIS as the motivation of our work that uses additional output buffer which guarantees that only correct data can enter the output channel. However this baseline RLIS suffers from performance degradations even when errors do not occur. We propose a novel improved RLIS that allows erroneous data to propagate in the system. Equipped with improved queues that prevent accumulation of erroneous data, the improved RLIS retains the system performance. We provide theoretical study that analyzes the impact of errors on system performance and the queue sizing problem. We also theoretically prove that the improved RLIS performs no worse than the global stalling mechanism. Experimental results show that the improved RLIS has 40.3% and even 3.1% throughput improvements compared to the baseline RLIS and the infeasible global stalling mechanism respectively, with less than 10% hardware overhead.
The interaction between information technology and phys ical world makes Cyber-Physical Systems (CPS) vulnerable to malicious attacks beyond the standard cyber attacks. This has motivated the need for attack-resilient state estimation. Yet, the existing state-estimators are based on the non-realistic assumption that the exact system model is known. Consequently, in this work we present a method for state estimation in presence of attacks, for systems with noise and modeling errors. When the the estimated states are used by a state-based feedback controller, we show that the attacker cannot destabilize the system by exploiting the difference between the model used for the state estimation and the real physical dynamics of the system. Furthermore, we describe how implementation issues such as jitter, latency and synchronization errors can be mapped into parameters of the state estimation procedure that describe modeling errors, and provide a bound on the state-estimation error caused by modeling errors. This enables mapping control performance requirements into real-time (i.e., timing related) specifications imposed on the underlying platform. Finally, we illustrate and experimentally evaluate this approach on an unmanned ground vehicle case-study.
The EIIM model for ER allows for creation and maintenance of persistent entity identity structures. It accomplishes this through a collection of batch configurations that allow updates and asserted fixes to be made to the Identity knowledgebase (IKB). The model also provides a batch IR configuration that provides no maintenance activity but instead allows access to the identity information. This batch IR configuration is limited in a few ways. It is driven by the same rules used for maintaining the IKB, has no inherent method to identity "close" matches, and can only identify and return the positive matches. Through the decoupling of this configuration and its movements into an interactive role under the umbrella of an Identity Management Service, a more robust access method can be provided for the use of identity information. This more robust access to the information improved the quality of the information along multiple Information Quality dimensions.
In recent years, Wireless Sensor Networks (WSNs) have become valuable assets to both the commercial and military communities with applications ranging from industrial control on a factory floor to reconnaissance of a hostile border. A typical WSN topology that applies to most applications allows sensors to act as data sources that forward their measurements to a central sink or base station (BS). The unique role of the BS makes it a natural target for an adversary that desires to achieve the most impactful attack possible against a WSN. An adversary may employ traffic analysis techniques such as evidence theory to identify the BS based on network traffic flow even when the WSN implements conventional security mechanisms. This motivates a need for WSN operators to achieve improved BS anonymity to protect the identity, role, and location of the BS. Many traffic analysis countermeasures have been proposed in literature, but are typically evaluated based on data traffic only, without considering the effects of network synchronization on anonymity performance. In this paper we use evidence theory analysis to examine the effects of WSN synchronization on BS anonymity by studying two commonly used protocols, Reference Broadcast Synchronization (RBS) and Timing-synch Protocol for Sensor Networks (TPSN).
The electric network frequency (ENF) signal can be captured in multimedia recordings due to electromagnetic influences from the power grid at the time of recording. Recent work has exploited the ENF signals for forensic applications, such as authenticating and detecting forgery of ENF-containing multimedia signals, and inferring their time and location of creation. In this paper, we explore a new potential of ENF signals for automatic synchronization of audio and video. The ENF signal as a time-varying random process can be used as a timing fingerprint of multimedia signals. Synchronization of audio and video recordings can be achieved by aligning their embedded ENF signals. We demonstrate the proposed scheme with two applications: multi-view video synchronization and synchronization of historical audio recordings. The experimental results show the ENF based synchronization approach is effective, and has the potential to solve problems that are intractable by other existing methods.
In this work, a new fingerprinting-based localization algorithm is proposed for an underwater medium by utilizing ultra-wideband (UWB) signals. In many conventional underwater systems, localization is accomplished by utilizing acoustic waves. On the other hand, electromagnetic waves haven't been employed for underwater localization due to the high attenuation of the signal in water. However, it is possible to use UWB signals for short-range underwater localization. In this work, the feasibility of performing localization for an underwater medium is illustrated by utilizing a fingerprinting-based localization approach. By employing the concept of compressive sampling, we propose a sparsity-based localization method for which we define a system model exploiting the spatial sparsity.
Providers of critical infrastructure services strive to maintain the high availability of their SCADA systems. This paper reports on our experience designing, architecting, and evaluating the first survivable SCADA system-one that is able to ensure correct behavior with minimal performance degradation even during cyber attacks that compromise part of the system. We describe the challenges we faced when integrating modern intrusion-tolerant protocols with a conventional SCADA architecture and present the techniques we developed to overcome these challenges. The results illustrate that our survivable SCADA system not only functions correctly in the face of a cyber attack, but that it also processes in excess of 20 000 messages per second with a latency of less than 30 ms, making it suitable for even large-scale deployments managing thousands of remote terminal units.
Complex event processing has become an important technology for big data and intelligent computing because it facilitates the creation of actionable, situational knowledge from potentially large amount events in soft realtime. Complex event processing can be instrumental for many mission-critical applications, such as business intelligence, algorithmic stock trading, and intrusion detection. Hence, the servers that carry out complex event processing must be made trustworthy. In this paper, we present a threat analysis on complex event processing systems and describe a set of mechanisms that can be used to control various threats. By exploiting the application semantics for typical event processing operations, we are able to design lightweight mechanisms that incur minimum runtime overhead appropriate for soft realtime computing.
The emerging paradigm of cloud computing, e.g., Amazon Elastic Compute Cloud (EC2), promises a highly flexible yet robust environment for large-scale applications. Ideally, while multiple virtual machines (VM) share the same physical resources (e.g., CPUs, caches, DRAM, and I/O devices), each application should be allocated to an independently managed VM and isolated from one another. Unfortunately, the absence of physical isolation inevitably opens doors to a number of security threats. In this paper, we demonstrate in EC2 a new type of security vulnerability caused by competition between virtual I/O workloads-i.e., by leveraging the competition for shared resources, an adversary could intentionally slow down the execution of a targeted application in a VM that shares the same hardware. In particular, we focus on I/O resources such as hard-drive throughput and/or network bandwidth-which are critical for data-intensive applications. We design and implement Swiper, a framework which uses a carefully designed workload to incur significant delays on the targeted application and VM with minimum cost (i.e., resource consumption). We conduct a comprehensive set of experiments in EC2, which clearly demonstrates that Swiper is capable of significantly slowing down various server applications while consuming a small amount of resources.
Using one password for all web services is not secure because the leakage of the password compromises all the web services accounts, while using independent passwords for different web services is inconvenient for the identity claimant to memorize. A password manager is used to address this security-convenience dilemma by storing and retrieving multiple existing passwords using one master password. On the other hand, a password manager liberates human brain by enabling people to generate strong passwords without worry about memorizing them. While a password manager provides a convenient and secure way to managing multiple passwords, it centralizes the passwords storage and shifts the risk of passwords leakage from distributed service providers to a software or token authenticated by a single master password. Concerned about this one master password based security, biometrics could be used as a second factor for authentication by verifying the ownership of the master password. However, biometrics based authentication is more privacy concerned than a non-biometric password manager. In this paper we propose a cloud password manager scheme exploiting privacy enhanced biometrics, which achieves both security and convenience in a privacy-enhanced way. The proposed password manager scheme relies on a cloud service to synchronize all local password manager clients in an encrypted form, which is efficient to deploy the updates and secure against untrusted cloud service providers.
Modern military forces are enabled by networked command and control systems, which provide an important interface between the cyber environment, electronic sensors and decision makers. However these systems are vulnerable to cyber attack. A successful cyber attack could compromise data within the system, leading to incorrect information being utilized for decisions with potentially catastrophic results on the battlefield. Degrading the utility of a system or the trust a decision maker has in their virtual display may not be the most effective means of employing offensive cyber effects. The coordination of cyber and kinetic effects is proposed as the optimal strategy for neutralizing an adversary's C4ISR advantage. However, such an approach is an opportunity cost and resource intensive. The adversary's cyber dependence can be leveraged as a means of gaining tactical and operational advantage in combat, if a military force is sufficiently trained and prepared to attack the entire information network. This paper proposes a research approach intended to broaden the understanding of the relationship between command and control systems and the human decision maker, as an interface for both cyber and kinetic deception activity.
- « first
- ‹ previous
- 1
- 2
- 3
- 4