This paper presents a channel operating margin (COM) based high-speed serial link optimization using machine learning (ML). COM that is proposed for evaluating serial link is calculated at first and during the calculation several important equalization parameters corresponding to the best configuration are extracted which can be used for the ML modeling of serial link. Then a deep neural network containing hidden layers are investigated to model a whole serial link equalization including transmitter feed forward equalizer (FFE), receiver continuous time linear equalizer (CTLE) and decision feedback equalizer (DFE). By training, validating and testing a lot of samples that meet the COM specification of 400GAUI-8 C2C, an effective ML model is generated and the maximum relative error is only 0.1 compared with computation results. At last 3 link configurations are discussed from the view of tradeoff between the link performance and cost, illustrating that our COM based ML modeling method can be applied to advanced serial link design for NRZ, PAM4 or even other higher level pulse amplitude modulation signal.
We propose a video authentication scheme to verify whether a given video file is recorded by a camera device or touched by a video editing tool. The proposed scheme prepares software characteristics of camera devices and video editing tools in advance, and compares them with the metadata of the given video file. Through practical implementation, we show that the proposed scheme has benefits of fast analysis time, high accuracy and full automation.
Fan WU He LI Wenhao FAN Bihua TANG Yuanan LIU
Android occupies a very large market share in the field of mobile devices, and quantities of applications are created everyday allowing users to easily use them. However, privacy leaks on Android terminals may result in serious losses to businesses and individuals. Current permission model cannot effectively prevent privacy data leakage. In this paper, we find a way to protect privacy data on Android terminals from the perspective of privacy information propagation by porting the concept of contextual integrity to the realm of privacy protection. We propose a computational model of contextual integrity suiting for Android platform and design a privacy protection system based on the model. The system consists of an online phase and offline phase; the main function of online phase is to computing the value of distribution norm and making privacy decisions, while the main function of offline phase is to create a classification model that can calculate the value of the appropriateness norm. Based on the 6 million permission requests records along with 2.3 million runtime contextual records collected by dynamic analysis, we build the system and verify its feasibility. Experiment shows that the accuracy of offline classifier reaches up to 0.94. The experiment of the overall system feasibility illustrates that 70% location data requests, 84% phone data requests and 46% storage requests etc., violate the contextual integrity.
Eun-Sung JUNG Si LIU Rajkumar KETTIMUTHU Sungwook CHUNG
The scale of scientific data generated by experimental facilities and simulations in high-performance computing facilities has been proliferating with the emergence of IoT-based big data. In many cases, this data must be transmitted rapidly and reliably to remote facilities for storage, analysis, or sharing, for the Internet of Things (IoT) applications. Simultaneously, IoT data can be verified using a checksum after the data has been written to the disk at the destination to ensure its integrity. However, this end-to-end integrity verification inevitably creates overheads (extra disk I/O and more computation). Thus, the overall data transfer time increases. In this article, we evaluate strategies to maximize the overlap between data transfer and checksum computation for astronomical observation data. Specifically, we examine file-level and block-level (with various block sizes) pipelining to overlap data transfer and checksum computation. We analyze these pipelining approaches in the context of GridFTP, a widely used protocol for scientific data transfers. Theoretical analysis and experiments are conducted to evaluate our methods. The results show that block-level pipelining is effective in maximizing the overlap mentioned above, and can improve the overall data transfer time with end-to-end integrity verification by up to 70% compared to the sequential execution of transfer and checksum, and by up to 60% compared to file-level pipelining.
Akira TSUCHIYA Akitaka HIRATSUKA Toshiyuki INOUE Keiji KISHINE Hidetoshi ONODERA
This paper discusses the impact of stacking on-chip inductor on power/ground network. Stacking inductor on other circuit components can reduce the circuit area drastically, however, the impact on signal and power integrity is not clear. We investigate the impact by a field-solver, a circuit simulator and real chip measurement. We evaluate three types of power/ground network and various multi-layered inductors. Experimental results show that dense power/ground structures reduce noise although the coupling capacitance becomes larger than that of sparse structures. Measurement in a 65-nm CMOS shows a woven structure makes the noise voltage half compared to a sparse structure.
In many applications, tables are distributively stored in different data sources, but the frequency of updates on each data source is different. Some techniques have been proposed to effectively express the temporal orders between different values, and the most current, i.e. up-to-date, value of a given data item can be easily picked up according to the temporal orders. However, the currency of the data items in the same table may be different. That is, when a user asks for a table D, it cannot be ensured that all the most current values of the data items in D are stored in a single table. Since different data sources may have overlaps, we can construct a conjunctive query on multiple tables to get all the required current values. In this paper, we formalize the conjunctive query as currency preserving query, and study how to generate the minimized currency preserving query to reduce the cost of visiting different data sources. First, a graph model is proposed to represent the distributed tables and their relationships. Based on the model, we prove that a currency preserving query is equivalent to a terminal tree in the graph, and give an algorithm to generate a query from a terminal tree. After that, we study the problem of finding minimized currency preserving query. The problem is proved to be NP-hard, and some heuristics strategies are provided to solve the problem. Finally, we conduct experiments on both synthetic and real data sets to verify the effectiveness and efficiency of the proposed techniques.
Masahiro KANO Toru NAKURA Tetsuya IIZUKA Kunihiro ASADA
This paper proposes a triangular active charge injection method to reduce resonant power supply noise by injecting the adequate amount of charge into the supply line of the LSI in response to the current consumption of the core circuit. The proposed circuit is composed of three key components, a voltage drop detector, an injection controller circuit and a canceling capacitor circuit. In addition to the theoretical analysis of the proposed method, the measurement results indicate that our proposed method with active capacitor can realize about 14% noise reduction compared with the original noise amplitude. The proposed circuit consumes 25.2 mW in steady state and occupies 0.182 mm2.
An efficient reciprocity and passivity preserving balanced truncation for RLC networks is presented in this paper. Reciprocity and passivity are fundamental principles of linear passive networks. Hence, reduction with preservation of reciprocity and passivity is necessary to simulate behavior of the circuits including the RLC networks accurately and stably. Moreover, the proposed method is more efficient than the previous balanced truncation methods, because sparsity patterns of the coefficient matrices for the circuit equations of the RLC networks are fully available. In the illustrative examples, we will show that the proposed method is compatible with PRIMA, which is known as a general reduction method of RLC networks, in efficiency and used memory, and is more accurate at high frequencies than PRIMA.
An efficient balanced truncation for RC and RLC networks is presented in this paper. To accelerate the balanced truncation, sparse structures of original networks are considered. As a result, Lyapunov equations, the solutions of which are necessary for making the transformation matrices, are efficiently solved, and the reduced order models are efficiently obtained. It is proven that reciprocity of original networks is preserved while applying the proposed method. Passivity of the reduced RC networks is also guaranteed. In the illustrative examples, we will show that the proposed method is compatible with PRIMA in efficiency and is more accurate than PRIMA.
Masahiro ISHIDA Toru NAKURA Takashi KUSAKA Satoshi KOMATSU Kunihiro ASADA
This paper proposes a power supply voltage control technique, and demonstrates its effectiveness for eliminating the overkills and underkills due to the power supply characteristic difference between an automatic test equipment (ATE) and a practical operating environment of the DUT. The proposed method controls the static power supply voltage on the ATE system, so that the ATE can eliminate misjudges for the Pass or Fail of the DUT. The method for calculating the power supply voltage is also described. Experimental results show that the proposed method can eliminate 89% of overkills and underkills in delay fault testing with 105 real silicon devices. Limitations of the proposed method are also discussed.
Yilun WU Xinye LIN Xicheng LU Jinshu SU Peixin CHEN
Public auditing is a new technique to protect the integrity of outsourced data in the remote cloud. Users delegate the ability of auditing to a third party auditor (TPA), and assume that each result from the TPA is correct. However, the TPA is not always trustworthy in reality. In this paper, we consider a scenario in which the TPA may lower the reputation of the cloud server by cheating users, and propose a novel public auditing scheme to address this security issue. The analyses and the evaluation prove that our scheme is both secure and efficient.
Huaqun WANG Keqiu LI Kaoru OTA Jian SHEN
In the health IoT (Internet of Things), the specialized sensor devices can be used to monitor remote health and notify the emergency information, e.g., blood pressure, heart rate, etc. These data can help the doctors to rescue the patients. In cloud-based health IoT, patients' medical/health data is managed by the cloud service providers. Secure storage and privacy preservation are indispensable for the outsourced medical/health data in cloud computing. In this paper, we study the integrity checking and sharing of outsourced private medical/health records for critical patients in public clouds (ICS). The patient can check his own medical/health data integrity and retrieve them. When a patient is in coma, some authorized entities and hospital can cooperate to share the patient's necessary medical/health data in order to rescue the patient. The paper studies the system model, security model and concrete scheme for ICS in public clouds. Based on the bilinear pairing technique, we design an efficient ICS protocol. Through security analysis and performance analysis, the proposed protocol is provably secure and efficient.
The alternating direction implicit (ADI) method is proposed for low-rank solution of projected generalized continuous-time algebraic Lyapunov equations. The low-rank solution is expressed by Cholesky factor that is similar to that of Cholesky factorization for linear system of equations. The Cholesky factor is represented in a real form so that it is useful for balanced truncation of sparsely connected RLC networks. Moreover, we show how to determine the shift parameters which are required for the ADI iterations, where Krylov subspace method is used for finding the shift parameters that reduce the residual error quickly. In the illustrative examples, we confirm that the real Cholesky factor certainly provides low-rank solution of projected generalized continuous-time algebraic Lyapunov equations. Effectiveness of the shift parameters determined by Krylov subspace method is also demonstrated.
Kazumasa OMOTE Phuong-Thao TRAN
Nowadays, many individuals and organizations tend to outsource their data to a cloud storage for reducing the burden of data storage and maintenance. However, a cloud provider may be untrustworthy. The cloud thus leads to a numerous security challenges: data availability, data integrity, and data confidentiality. In this paper, we focus on data availability and data integrity because they are the prerequisites of the existence of a cloud system. The approach of this paper is the network coding-based Proof of Retrievability (POR) scheme which allows a client to check whether his/her data stored on the cloud servers are intact. Although many existing network coding-based PORs have been proposed, most of them still incur high costs in data check and data repair, and cannot prevent the small corruption attack which is a common attack in the POR scheme. This paper proposes a new network coding-based POR using the dispersal coding technique, named the ND-POR (Network coding - Dispersal coding POR) to improve the efficiency in data check and data repair and to protect against the small corruption attack.
Toru NAKURA Masahiro KANO Masamitsu YOSHIZAWA Atsunori HATTORI Kunihiro ASADA
This paper demonstrates the resonant power supply noise reduction effects of STO thin film decoupling capacitors, which are embedded in interposers. The on-interposer STO capacitor consists of SrTiO2 whose dielectric constant is about 20 and is sandwitched by Cu films in an interposer. The on-interposer STO capacitors are directly connected to the LSI PADs so that they provide large decoupling capacitance without package leadframe/bonding wire inductance, resulting in the reduction of the resonant power supply noise. The measured power supply waveforms show significant reduction of the power supply noise, and the Shmoo plots also show the contribution of the STO capacitors to the robust operations of LSIs.
Fast simulation techniques of large scale RLC networks with nonlinear devices are presented. Generally, when scale of nonlinear part in a circuit is much less than the linear part, matrix or circuit partitioning approach is known to be efficient. In this paper, these partitioning techniques are used for the conventional transient analysis using an implicit numerical integration and the circuit-based finite-difference time-domain (FDTD) method, whose efficiency and accuracy are evaluated developing a prototype simulator. It is confirmed that the matrix and circuit partitioning approaches do not degrade accuracy of the transient simulations that is compatible to SPICE, and that the circuit partitioning approach is superior to the matrix one in efficiency. Moreover, it is demonstrated that the circuit-based FDTD method can be efficiently combined with the matrix or circuit partitioning approach, compared with the transient analysis using an implicit numerical integration.
Sangwook LEE Ji Eun SONG Wan Yeon LEE Young Woong KO Heejo LEE
For digital forensic investigations, the proposed scheme verifies the integrity of video contents in legacy surveillance camera systems with no built-in integrity protection. The scheme exploits video frames remaining in slack space of storage media, instead of timestamp information vulnerable to tampering. The scheme is applied to integrity verification of video contents formatted with AVI or MP4 files in automobile blackboxes.
The second edition of the international standard of IEC 61508, functional safety of electrical/electronic/programmable electronic safety-related system (SRS), was published in 2010. This international standard adopts a risk-based approach by which safety integrity requirements can be determined. It presents a formula to estimate the hazardous event rate taking account of non-perfect proof-tests. But it is not clear how to derive the formula. In the present paper, firstly, taking account of non-perfect proof-tests, the relationship between the dangerous undetected failure of SRS, the demand on the SRS and hazardous event is modeled by a fault tree and state-transition diagrams. Next, the hazardous event rate is formulated by use of the state-transition diagrams for the determination of the safety integrity requirements. Then, a comparison is made between the formulas obtained by this paper and given in the standard, and it is found that the latter does not always present rational formulation.
Satoshi TAKAYA Hiroaki IKEDA Makoto NAGATA
A three dimensional (3D) chip stack featuring a 4096-bit wide I/O demonstrator incorporates an in-place waveform capturer on an intermediate interposer within the stack. The capturer includes probing channels on paths of signaling as well as in power delivery and collects analog waveforms for diagnosing circuits within 3D integration. The collection of in-place waveforms on vertical channels with through silicon vias (TSVs) are demonstrated among 128 vertical I/O channels distributed in 8 banks in a 9.9mm × 9.9mm die area. The analog waveforms confirm a full 1.2-V swing of signaling at the maximum data transmission bandwidth of 100GByte/sec with sufficiently small deviations of signal skews and slews among the vertical channels. In addition, it is also experimentally confirmed that the signal swing can be reduced to 0.75V for error free data transfer at 100GByte/sec, achieving the energy efficiency of 0.21pJ/bit.
Kumpei YOSHIKAWA Kouji ICHIKAWA Makoto NAGATA
An LSI Chip-Package-Board integrated power noise simulation model and its validity is discussed in this paper. A unified power delivery network (PDN) of LSI chip, package, and printed circuit board (PCB) is connected with on-chip power supply current models with capacitor charging expression. The proposed modeling flow is demonstrated for the 32-bit microprocessor in a 1.0V 90nm CMOS technology. The PDN of the system that includes a chip, bonding wires and a printed circuit board is modeled in an equivalent circuit. The on-chip power supply noise monitoring technique and the magnetic probe method is applied for validating simulation results. Simulations and measurements explore power supply noise generation with the dependency on operating frequencies in the wide range from 10MHz to 300MHz, under the operation mode of dynamic frequency scaling, and in the long time operation with various operation codes. It is confirmed that the proposed power supply noise simulation model is helpful for the noise estimation throughout the design phase of the LSI system.