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Pervasive computing environments focus on integrating computing and communications with the surrounding physical environment. As a potential threat in the physical environment, fault attacks using the injection of practical faults have been introduced for extracting secret keys stored in low-cost devices. In particular, the advanced encryption standard (AES) has been broken by various fault attacks, and satisfactory countermeasures have yet to be introduced. This paper proposes a new countermeasure that can prevent fault attacks by verifying differential bytes of input and output in the encryption process and the key expansion process, respectively. The results of computer simulations and fault injection experiments verify that the proposed countermeasure against fault attacks outperforms existing countermeasures in terms of fault detection and efficiency.

In this paper, we propose a novel optical fault detection scheme for RSA hardware based on Montgomery exponentiation, which can effectively detect optical fault injection during the exponent calculation. To protect the RSA hardware from the optical fault injection attack, we implemented integrity check logic for memory and optical fault detection logic for Montgomery-based multiplier. The proposed scheme is considered to be safe from various type of attack and it can be implemented with no additional operation time and small area overhead which is less than 3%.

Delivery drones are unmanned aerial vehicles (UAV) utilized to transport packages, food, medicine, or other goods. With high demand for a prompt and efficient delivery, a drone delivery system can be an effective solution for timely deliveries and especially for emergency management. However, current delivery drone systems lack crucial security functions. Drones may have to operate in unsupervised hostile areas, and therefore be vulnerable to physical capture in addition to conventional cyber attacks. A captured drone can be analyzed by a white-box attack model in which the attacker has full control over the execution environment of cryptographic modules in static and dynamic methods including all side-channel information. In this paper, we propose and evaluate a security framework which utilizes white-box cryptography in order to protect critical data and cryptographic keys in delivery drones from white-box attacks. The experimental results show that the proposed framework is cost effective in terms of resource usage and thus is suitable even for resource-limited UAV.

Radio frequency identification RFID has received much attention both in industry and academia in recent years. To this extent, the international standards group, ISO/IEC JTC 1/SC 31, is in the midst of standardization activity to define the security extension to the EPCglobal Generation 2 Gen2 ultra high frequency UHF air interface protocols for secure RFID communications. In this paper, we investigate a vulnerability of an RFID mutual authentication protocol that was highlighted in a recent letteri¾?[5]. Our analysis presents that the attack on the mutual authentication protocol is just a relay operation between a legitimate reader and a legitimate tag. We also propose the threshold values of data rate between a reader and a tag based on link timing parameters of passive UHF RFID systems.

A typical approach, to protect a given symmetric key cryptographic algorithm against differential power analysisDPA, is a masking method which is to randomize all intermediate values of the cryptographic algorithm and the main time-consuming part of the masking method is to generate masked S-Boxes. The masked S-Boxes are implemented by generating the look-up tables for most of DPA countermeasures in the software manner. In this paper, we present an improved masking scheme that makes the efficient masked S-Boxes by revisiting the ways to use the low composite fields arithmetic. Our improved masking scheme is basically slower than the standard AES implementation, but much faster than existing method which makes a whole S-Box random with 16 masks. In addition, our scheme is 20$$\%$$ faster using less memory, compared to Oswald's work using the similar method with the proposed approach. In other case of our scheme, we reduce almost half of memory with 9$$\%$$ slow rate. We concentrate on the trade-off between memory sizes and operation speed.

The block cipher ARIA has been threatened by sidechannel analysis, and much research on countermeasures of this attack has also been produced. However, studies on countermeasures of ARIA are focused on software implementation, and there are no reports about hardware designs and their performance evaluation. Therefore, this article presents an advanced masking algorithm which is strong against second-order differential power analysis (SODPA) and implements a secure ARIA hardware. As there is no comparable report, the proposed masking algorithm used in our hardware module is evaluated using a comparison result of software implementations. Furthermore, we implement the proposed algorithm in three types of hardware architectures and compare them. The smallest module is 10,740 gates in size and consumes an average of 47.47 μW in power consumption. Finally, we make ASIC chips with the proposed design, and then perform security verification. As a result, the proposed module is small, energy efficient, and secure against SODPA.

Since card-type one-time password (OTP) generators became available, power and area consumption has been one of the main issues of hardware OTPs. Because relatively smaller batteries and smaller chip areas are available for this type of OTP compared to existing tokentype OTPs, it is necessary to implement power-efficient and compact dedicated OTP hardware modules. In this paper, we design and implement a low-power small-area hardware OTP generator based on the Advanced Encryption Standard (AES). First, we implement a prototype AES hardware module using a 350 nm process to verify the effectiveness of our optimization techniques for the SubBytes transform and data storage. Next, we apply the optimized AES to a real-world OTP hardware module which is implemented using a 180 nm process. Our experimental results show the power consumption of our OTP module using the new AES implementation is only 49.4% and 15.0% of those of an HOTP and softwarebased OTP, respectively.

This paper presents a practical differential fault analysis method for the faulty Advanced Encryption Standard (AES) with a reduced round by means of a semi-invasive fault injection. To verify our proposal, we implement the AES software on the ATmega128 microcontroller as recommended in the standard document FIPS 197. We reduce the number of rounds using a laser beam injection in the experiment. To deduce the initial round key, we perform an exhaustive search for possible key bytes associated with faulty ciphertexts. Based on the simulation result, our proposal extracts the AES 128-bit secret key in less than 10 hours with 10 pairs of plaintext and faulty ciphertext.

This paper proposes an efficient masking method for the block cipher SEED that is standardized in Korea. The nonlinear parts of SEED consist of two S-boxes and modular additions. However, the masked version of these nonlinear parts requires excessive RAM usage and a large number of operations. Protecting SEED by the general masking method requires 512 bytes of RAM corresponding to masked S-boxes and a large number of operations corresponding to the masked addition. This paper proposes a new-style masked S-box which can reduce the amount of operations of the masking addition process as well as the RAM usage. The proposed masked SEED, equipped with the new-style masked S-box, reduces the RAM requirements to 288 bytes, and it also reduces the processing time by 38% compared with the masked SEED using the general masked S-box. The proposed method also applies to other block ciphers with the same nonlinear operations.

In the recent years, power attacks were widely investigated, and so various countermeasures have been proposed. In the case of block ciphers, masking methods that blind the intermediate results in the algorithm computations(encryption, decryption) are well-known. In case of SEED block cipher, it uses 32 bit arithmetic addition and S-box operations as non-linear operations. Therefore the masking type conversion operations, which require some operating time and memory, are required to satisfy the masking method of all non-linear operations. In this paper, we propose a new masked S-boxes that can minimize the number of the masking type conversion operation. Moreover we construct just one masked S-box table and propose a new formula that can compute the other masked S-box's output by using this S-box table. Therefore the memory requirements for masked S-boxes are reduced to half of the existing masking method's one.

The NTRU cryptosystem is a public key system based on lattice problems. While its theoretical security has been well studied, little effort has been made to analyze its security against implementation attacks including power analysis attacks. In this paper, we show that a typical software implementation of NTRU is vulnerable to the simple power analysis and the correlation power analysis including a second-order power attack. We also present novel countermeasures to prevent these attacks, and perform experiments to estimate the performance overheads of our countermeasures. According to our experimental results, the overheads in required memory and execution time are only 8.17% and 9.56%, respectively, over a Tmote Sky equipped with an MSP430 processor.

A side channel analysis is a very efficient attack against small devices such as smart cards and wireless sensor nodes. In this paper, we propose an efficient key detection method using a peak selection algorithm in order to find the advanced encryption standard secret key from electromagnetic signals. The proposed method is applied to a correlation electromagnetic analysis (CEMA) attack against a wireless sensor node. Our approach results in increase in the correlation coefficient in comparison with the general CEMA. The experimental results show that the proposed method can efficiently and reliably uncover the entire 128-bit key with a small number of traces, whereas some extant methods can reveal only partial subkeys by using a large number of traces in the same conditions.

Pairing-based cryptography provides us many novel cryptographic applications such as ID-based cryptosystems and efficient broadcast encryptions. The security problems in ubiquitous sensor networks have been discussed in many papers, and pairing-based cryptography is a crucial technique to solve them. Due to the limited resources in the current sensor node, it is challenged to optimize the implementation of pairings on sensor nodes. In this paper we present an efficient implementation of pairing over MICAz, which is widely used as a sensor node for ubiquitous sensor network. We improved the speed of ηT pairing by using a new efficient multiplication specialized for ATmega128L, called the block comb method and several optimization techniques to save the number of data load/store operations. The timing of ηT pairing over GF(2239) achieves about 1.93sec, which is the fastest implementation of pairing over MICAz to the best of our knowledge. From our dramatic improvement, we now have much high possibility to make pairing-based cryptography for ubiquitous sensor networks practical.

This paper provides an efficient algorithm for computing the η T pairing on supersingular elliptic curves over fields of characteristic two. In the proposed algorithm, we deploy a modified multiplication in F 2 4n using the Vandermonde matrix. For F, G ∈F 2 4n, the proposed multiplication method computes β·F·G instead of F · G with some β ∈ F* 2 n because β is eliminated by the final exponentiation of the η T pairing computation. The proposed multiplication method asymptotically requires only 7 multiplications in F 2 n as n → ∞, while the cost of the previously fastest Karatsuba method is 9 multiplications in F 2 n·Consequently, the cost of the η T pairing computation is reduced by 14.3%.

In this paper, we study exponentiation in the specific finite fields F, with very special exponents such as those that occur in algorithms for computing square roots. Here, q is a prime power, q = pk, where k > 1, and k is odd. Our algorithmic approach improves the corresponding exponentiation resulted from the better rewritten exponent. To the best of our knowledge, it is the first major improvement to the Tonelli-Shanks algorithm, for example, the number of multiplications can be reduced to at least 60 percent on the average when p= 1 (mod 16). Several numerical examples are given that show the speedup of the proposed methods.

The randomized projective coordinate (RPC) method applied to a pairing computation algorithm is a good solution that provides an efficient countermeasure against side channel attacks. In this study, we investigate measures for increasing the efficiency of the RPC-based countermeasures and construct a method that provides an efficient RPC-based countermeasure against side channel attacks. We then apply our method to the well-known η T pairing algorithm over binary fields and obtain an RPC-based countermeasure for the η T pairing; our method is more efficient than the RPC method applied to the original η T pairing algorithm.

This paper presents the design and implementation of a hyperelliptic curve cryptography (HECC) coprocessor over affine and projective coordinates, along with measurements of its performance, hardware complexity, and power consumption. We applied several design techniques, including parallelism, pipelining, and loop unrolling, in designing field arithmetic units, group operation units, and scalar multiplication units to improve the performance and power consumption. Our affine and projective coordinate-based HECC processors execute in 0.436 ms and 0.531 ms, respectively, based on the underlying field GF(2 89 ). These results are about five times faster than those for previous hardware implementations and at least 13 times better in terms of area-time products. Further results suggest that neither case is superior to the other when considering the hardware complexity and performance. The characteristics of our proposed HECC coprocessor show that it is applicable to high-speed network applications as well as resource-constrained environments, such as PDAs, smart cards, and so on.

Document filter extracts text of UTF-16, Unicode or UTF-8 format from documents files of smart device. The extracted text is used at viewer and index search of smart device. This paper researches document filter of text based smart device files. The result of this research is useful to develop the mobile device search, which lets you find easily all your docs, pdf, text and email on smart device.

Side channel analysis is a powerful cryptanalytic method to reveal secret information of cryptographic devices such as smart cards, USB tokens, OTP devices and secure embedded devices. To prevent side channel attacks we must implement countermeasures against it and evaluate security of these implementations. However, secure embedded devices except smart cards are not easy to evaluate security of them against SCA owing to their complicated components and circumstances. In this paper we designed boards for SCA evaluation of software implementations and tested them with block cipher algorithms.

Masking schemes have been developed to implement secure cryptographic algorithms against Side Channel Analysis(SCA) attacks. Technically, the first-order masking method is vulnerable to the second order Differential Power Analysis(2ODPA) attacks, but the current solutions against 2ODPA are expensive to implement. Moreover, worse performance will be shown if the cryptographic algorithms include boolean and arithmetic operations. In this paper, we propose a new masking scheme to resist SCA attacks, which is called the Function Masking. Function Masking method conceals functions instead of data in the algorithms and makes it resistant to attacks as much as 2ODPA. We apply our masking scheme to the HIGHT algorithm. The encryption of function masked HIGHT takes only 1.79 times more than one of the original algorithm, even though it needs 25 kbytes to store lookup tables in memory.

Extensive research on modern cryptography ensures significant mathematical immunity to conventional cryptographic attacks. However, different side channel techniques such as power analysis and electromagnetic attacks are such a powerful tool to extract the secret key from cryptographic devices. These techniques bring serious threat on hardware implementations of cryptographic algorithms. In this paper an extensive analysis of side channel analysis on cryptographic device is presented where we study on the EM and PA attacks methods as sideways attacks on the hardware implementation of the crypto-module. Finally we establish a comparison table among different attacks tools methods for the accuracy analysis.

We investigated the reproducible and memory resistance switching characteristics of pulsed-laser deposited thin polycrystalline Nb"2O"5 film for application to nonvolatile memory devices. Reproducible switching cycles were observed, and the resistance ratios of two distinct conduction states were approximately two orders of magnitude. Two resistance switching states were also obtained for pulse duration as much as 10 ns. The degradation of both resistance states at 125 ^oC, indicating memory characteristics, was expected within 8 percent for 10 years. We also investigated the temperature-dependent conduction mechanisms of the high resistance state and the low resistance state, and we discussed a plausible resistance switching mechanism.

With the rapid progress of RFID security technologies, the international standard group ISO/IEC JTC 1/SC 31 is developing a few security technologies for RFID systems. One of the initial proposals is ISO/IEC working draft (WD) 29167-6. Recently, Song and others stated that Protocol 1 of ISO/IEC WD 29167-6 is vulnerable to a malicious adversary. However, their analysis comes from a misunderstanding regarding a communication parameter called Handle. In this letter, we point out that an adversary cannot obtain any sensitive information from intervening in Protocol 1.

A 1-bridge torus knot in a 3-manifold of genus ≤ 1 is a knot drawn on a Heegaard torus with one bridge. We give two types of normal forms to parameterize the family of 1-bridge torus knots that are similar to the Schubert's normal form and the Conway's normal form for 2-bridge knots. For a given Schubert's normal form we give algorithms to determine the number of components and to compute the fundamental group of the complement when the normal form determines a knot. We also give a description of the double branched cover of an ambient 3-manifold branched along a 1-bridge torus knot by using its Conway's normal form and obtain an explicit formula for the first homology of the double cover.

Although there is no theoretical weakness in a cryptographic algorithm, Side Channel Analysis can find out some secret data from the physical implementation of a cryptosystem. The analysis is based on extra information such as timing information, power consumption, electromagnetic leaks or even sound which can be exploited to break the system. Differential Power Analysis is one of the most popular analyses, as computing the statistical correlations of the secret keys and power consumptions. It is usually necessary to calculate huge data and takes a long time. It may take several weeks for some devices with countermeasures. We suggest and evaluate the methods to shorten the time to analyze cryptosystems. Our methods include distributed computing and parallelized processing., {"references":["P. Kocher, J. Jaffe, and B. Jun, Differential power analysis, Advances In Cryptology - CRYPTO' 99, LNCS 1666 Springer-Verlag, pp. 388-397, Santa Barbara, USA, August 1999","S. B. Örs, E. Oswald, B. Preneel, Power-Analysis Attacks on an FPGA - First Experimental Results, CHES 2003.","Hans ChristophHudde, GPU assisted Mutual Information Analysis Attacks on AES, Bachelor Thesis, Ruhr-Universität Bochum, April 2010","Riscure Inspector, https://www.riscure.com/security-tools/inspector-sca/, 2014.3","Brightsight Sideways, http://www.brightsight.com/tools/sideways, 2014.3"]}

International audience

Cryptographic Engineering is defined by the discipline of using cryptography to solve human problems (from the Wikipedia [1]). Main focus of the cryptographic engineering is to implement the cryptographic primitives based on mathematics to the real world device as the manner of software or hardware. Therefore, to study the cryptographic engineering field, mathematics backgrounds are needed as well as the computer engineering and computer science. In this article, we briefly review the trend of the cryptographic engineering field for the last decade. After that, side-channel attack for the crypto modules are introduced and several efforts are explained for preventing the side-channel attack in the area of the cryptographic engineering.

The resistance switching behavior and switching mechanism of nonstoichiometric zirconium oxide thin films were investigated for nonvolatile memory application. The Pt/ZrO/sub x//p/sup +/-Si sandwich structure fabricated by reactive sputtering shows two stable resistance states. By applying proper bias, resistance switching from one to another state can be obtained. The composition in ZrO/sub x/ thin films were confirmed from X-ray photoelectron spectroscope (XPS) analysis, which showed three layers such as top stoichiometric ZrO/sub 2/ layer with high resistance, transition region with medium resistance, and conducting ZrO/sub x/ bulk layer. The resistance switching can be explained by electron trapping and detrapping of excess Zr/sup +/ ions in transition layer which control the distribution of electric field inside the oxide, and, hence the current flow.

The resistance switching characteristics of polycrystalline Nb/sub 2/O/sub 5/ film prepared by pulsed-laser deposition (PLD) were investigated for nonvolatile memory application. Reversible resistance-switching behavior from a high resistance state to a lower state was observed by voltage stress with current compliance. The reproducible resistance-switching cycles were observed and the resistance ratio was as high as 50-100 times. The resistance switching was observed under voltage pulse as short as 10 ns. The estimated retention lifetime at 85/spl deg/C was sufficiently longer than ten years. Considering its excellent electrical and reliability characteristics, Nb/sub 2/O/sub 5/ shows strong promise for future nonvolatile memory applications.

This work demonstrates an anisotropic increase in resistivity with decreasing width in single crystal tungsten (W) nanowires having a height of 21 nm. Nanowire-widths were in the range of 15–451 nm, with the anisotropy observed for widths below 50 nm. The longitudinal directions of the nanowires coincided with the , and orientations of the body centered cubic phase of W. The resistivity increase was observed to be minimized for the -oriented single crystal nanowires, exhibiting a factor of two lower increase in resistivity at a width of ~15 nm, relative to the thin film resistivity (i.e., an infinitely wide wire). The observed anisotropy is attributed to crystallographic anisotropy of the Fermi velocity and the resultant anisotropy of the electron mean free path in W and underscores the critical role of crystallographic orientation in nanoscale metallic conduction.

Crystal orientation mapping in the transmission electron microscope was used to quantify the twin boundary length fraction per unit area for five Ta38Si14N48/SiO2 encapsulated Cu films with thicknesses in the range of 26–111 nm. The length fraction was found to be higher for a given twin-excluded grain size for these films compared with previously investigated SiO2 and Ta/SiO2 encapsulated films. The quantification of the twin length fraction per unit area allowed the contribution of the twin boundaries to the size effect resistivity to be assessed. It is shown that the increased resistivity of the Ta38Si14N48 encapsulated Cu films compared with the SiO2 and Ta/SiO2 encapsulated films is not a result of increased surface scattering, but it is a result of the increase in the density of twin boundaries. With twin boundaries included in the determination of grain size as a mean-intercept length, the resistivity data are well described by 2-parameter Matthiessen's rule summation of the Fuchs-Sondheimer and Ma...

Cloud storage services possibly store only a single copy of redundant data to save disk space and provide links to that copy rather storing other actual copies of data. This is called deduplication. If deduplication is performed across different accounts at each client side, this is classified into cross-user source-based deduplication. However, cross-user source-based deduplication can server as a side-channel of breaching user's privacy. To protect user's privacy, Harnik et al. proposed a randomized solution for cross-user source-based deduplication, user's privacy is, however, still at risk with a high probability. In this paper, we propose a new cross-user source-based deduplication providing dramatically enhanced security.

This work describes a study of the classical electrical resistivity size effect in tungsten. The important length scale for this size effect is the isotropic average electron mean free path (EMFP), which was determined to be 19.1 nm for W at 293 K by employing density functional theory. To explore the size effect experimentally, (110) oriented epitaxial W films with thicknesses ranging from 9.8 to 299.7 nm were prepared by sputter deposition onto ($11\overline{2}0$) Al${}_{2}$O${}_{3}$ substrates at 520 \ifmmode^\circ\else\textdegree\fi{}C followed by postdeposition annealing in Ar-4$%$H${}_{2}$ at 850 \ifmmode^\circ\else\textdegree\fi{}C. Film resistivities were measured at room temperature and at liquid He temperature. The Fuchs-Sondheimer (FS) surface scattering model with a low specularity parameter ($p$ $=$ 0.11) was shown to provide a good description of the film resistivity as a function of film thickness. Further, it is shown that an upper bound to the EMFP cannot be established by fitting resistivity data to the FS model, whereas a lower bound can be assessed.

RSA is one of the most widely used public key algorithms, and the RSA-CRT variation is applied to improve efficiency of operations. Since Power analysis attacks were introduced, many researchers have studied not only power analysis attacks of RSA but also CRT specified attacks. Boer et al. [3] proposed a new analysis method for finding r = x mod p with equidistant chosen plaintexts. From the knowledge of r, we can compute a secret prime number p. As this method is based on equidistant messages, unlike general power analysis methods, it is called MRED (Modular reduction on equidistant data) power analysis or ECMPA (Equidistant Chosen Message Power Analysis). Since there are various novel characteristics in equidistant messages, there exist unusual properties of ghost keys that are not seen in general power attacks. In this paper, we describe unknown and interesting characteristics of ghost key patterns using real experiments.

This paper presents a practical Differential Fault Analysis (DFA) method for the iterative operation on the SubBytes transformation AES. To inject a fault to the iterative operation, we conduct an experiment using a laser injection tool. And, then to deduce the last round key, we analyze the relationship between the input of S-Box and the output of S-Box. Based on a computer analysis, our proposal fault attack retrieves the AES 128-bit secret key with about 211 complexity in average using one pair of correct and faulty ciphertext.

This paper considers a secure and efficient CRT-RSA scheme resistant to fault attacks. Recently, Boscher et al. proposed a secure CRT-RSA scheme by verifying signature using a public exponent. However, it is almost two times slower compared to the classical CRT-RSA signature when the exponent is expected to be a long number. We present a low-cost and secure CRT-RSA scheme by generating a small exponent for checking the correctness of signature. Furthermore, since our scheme can use fast double exponentiation algorithm based on right-to-left binary method having two exponents, it has low computational load compared to other existing schemes.

Wireless sensor network which has more weak security than general network is not considering management principles although it is used in a various part. This paper is concerned with the security management system for sensor network including security function. We design the sensor network management functions and implement the system to manage the security information for detecting an attack from the illegal sensor node.

The RFID system is very much used until it reaches the various services including the physical distribution, circulation, military affairs, health care. The RFID system to a now came to the passive tag itself along the normal distribution route, we could not know. The RFID STAMP SYSTE to be proposed is designed so that it overcomes these disadvantages and we can trace the distribution route with each passive type reader.

This paper is about hiding RFID tag identifier (ID) using handheld device like a cellular phone. By modifying the tag ID of objects periodically or manually using cellular phone built-in a RFID reader chip or with a external RFID reader device, we can prevent other people from gathering the information related with objects querying information server (like an EPC IS) with a tag ID or deriving the information from tag ID-s code structure or tracking the location of the objects and the owner of the objects. In this paper, we use a cryptographic algorithm for modification and restoring of RFID tag ID, and for one original tag ID, there are several different temporary tag ID, periodically.

We propose a product authentication service which is anti-counterfeiting technology and can be applied to both the supply chain (SCM) and forthcoming mobile RFID environment. It aims to become aware of distribution of spurious products with fake RFID tags and to provide a product authentication service to consumers with mobile RFID devices like mobile phone which has a RFID reader. We also propose an authentication mechanism between a tag and an information server through the device. The mechanism is designed to be appropriated for EPC Class-1 Generation-2 UHF tags. The tags, one of RFID tag types, is expected that most companies are planning to use it in the SCM in the short term and in consumer packaging in the long term due to its inexpensive cost. Because of the very cost, however, its resources are extremely scarce and it is hard to have any valuable security algorithms in it. It causes security vulnerabilities, in particular cloning the tags for counterfeits. The mechanism provides secure mutual authentication between a tag and a server. It can be applied to the mobile RFID environment that any mobile RFID reader can be placed in the interface between the tag and the server. It means that the mechanism provides secure communication between them even the reader is not trusted. On basis of this tag authentication, the service makes use of location information especially from LBS (location based service) of the consumers' devices. Thanks to it, the service can make fine-grained decision about authentication of a product. At the same time the server utilize the information to extend its management area where legacy SCM could not reach thanks to consumers' mobile RFID devices

We have investigated single crystal Nb-doped SrTiO3 in terms of its potential utility in nonvolatile memory applications. Compared with polycrystalline oxide (Nb2O5, ZrO x and Cr-SrTiO3), the Pt/single crystal Nb:SrTiO 3 Schottky junction exhibits excellent memory characteristics including uniformity of set/reset bias, die-to-die reproducibility, data retention at high temperature, reliability under cycle stress, and multi-bit operation characteristics. The switching mechanism might be explained by modulation of the Schottky barrier height by charge trapping at the interface

Mobile IP, which was designed at the working group of IETF, intended to enable nodes to move from one IP subnet to another. That is, it can support node mobility across heterogeneous networks. For this mobility support, a mobile node (MN) must achieve registration at a home agent (HA) when the MN is away from home. In this article, we propose a mobile IP authentication that is based on an identification scheme using a one-way function. It ensures a secure mobile IP authentication against replay attack and man-in-the-middle attack. Furthermore, its implementation is expected to be efficient, since it does not use any public key cryptography operations.

The authors have investigated the resistance switching characteristics of non-stoichiometric ZrOx and STOx thin films for nonvolatile memory application. The non-stoichiometric ZrOx films were grown in a reactive sputtering method using Zr target and SrTiOx (STOx) films were deposited by pulsed laser deposition (PLD) method using a pure SrTiO3 target

For Low Latency Handoffs(LLH) [1] to be fast and effective, the Mobile IP session keys distributed by home AAA(Authentication, Authorization, and Accounting) server should be reused [2]. This can decrease the number of signaling messages to the home network, and reduce the signaling delay when a mobile node moves from one foreign agent to another, within the same visited domain. To reuse the session keys in a secure fashion, we present a method that performs the LLH without requiring further involvement by home AAA server. To prevent session stealing attack, the method provides the confidentiality and integrity of session keys in the phase of key exchange between old foreign agent and new foreign agent by using Diffie-Hellman key agreement. It allows the mobile node to perform LLH with fast as well as secure operation.