scholarly journals Ordinal synchronization mark sequence and its steganography for a multi-link network covert channel

PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0252813
Author(s):  
Songyin Fu ◽  
Rangding Wang ◽  
Li Dong ◽  
Diqun Yan
Keyword(s):  
Hash Function ◽  
High Capacity ◽  
Superior Performance ◽  
Covert Channel ◽  
Correlation Test ◽  
Switching Patterns ◽  
Finite Set ◽  
Set Up ◽  
Network Covert Channel ◽  
Real Traffic

A multi-link network covert channel (MLCC) such as Cloak exhibits a high capacity and robustness and can achieve lossless modulation of the protocol data units. However, the mechanism of Cloak involving an arrangement of packets over the links (APL) is limited by its passive synchronization schemes, which results in intermittent obstructions in transmitting APL packets and anomalous link switching patterns. In this work, we propose a novel ordinal synchronization mark sequence (OSMS) for a Cloak framework based MLCC to ensure that the marked APL packets are orderly distinguishable. Specifically, a unidirectional function is used to generate the OSMS randomly before realizing covert modulation. Subsequently, we formulate the generation relation of the marks according to their order and embed each mark into the APL packets by using a one-way hash function such that the mark cannot be cracked during the transmission of the APL packet. Finally, we set up a retrieval function of the finite set at the covert receiver to extract the marks and determine their orders, and the APL packets are reorganized to realize covert demodulation. The results of experiments performed on real traffic indicated that the MLCC embedded with OSMS could avoid the passive synchronization schemes and exhibited superior performance in terms of reliability, throughput, and undetectability compared with the renowned Cloak method, especially under a malicious network interference scenario. Furthermore, our approach could effectively resist the inter-link correlation test, which are highly effective in testing the Cloak framework.

On completely recursively enumerable classes and their key arrays

1956 ◽  
Vol 21 (3) ◽  
pp. 304-308 ◽  
Author(s):  
H. G. Rice
Keyword(s):  
Decision Procedure ◽  
Cardinal Number ◽  
Maximum Amount ◽  
Infinite Class ◽  
Finite Sets ◽  
Amount Of Information ◽  
Recursively Enumerable ◽  
Finite Set ◽  
Partial Recursive Functions ◽  
Set Up

The two results of this paper (a theorem and an example) are applications of a device described in section 1. Our notation is that of [4], with which we assume familiarity. It may be worth while to mention in particular the function Φ(n, x) which recursively enumerates the partial recursive functions of one variable, the Cantor enumerating functions J(x, y), K(x), L(x), and the classes F and Q of r.e. (recursively enumerable) and finite sets respectively.It is possible to “give” a finite set in a way which conveys the maximum amount of information; this may be called “giving explicitly”, and it requires that in addition to an effective enumeration or decision procedure for the set we give its cardinal number. It is sometimes desired to enumerate effectively an infinite class of finite sets, each given explicitly (e.g., [4] p. 360, or Dekker [1] p. 497), and we suggest here a device for doing this.We set up an effective one-to-one correspondence between the finite sets of non-negative integers and these integers themselves: the integer , corresponds to the set αi, = {a1, a2, …, an} and inversely. α0 is the empty set. Clearly i can be effectively computed from the elements of αi and its cardinal number.

scholarly journals Deep Learning-Based Image Automatic Assessment and Nursing of Upper Limb Motor Function in Stroke Patients

2021 ◽  
Vol 2021 ◽  
pp. 1-6
Author(s):  
Xue Chen ◽  
Yuanyuan Shi ◽  
Yanjun Wang ◽  
Yuanjuan Cheng
Keyword(s):  
Deep Learning ◽  
Upper Limb ◽  
Spatial Location ◽  
Two Dimensions ◽  
Superior Performance ◽  
Coefficient Of Determination ◽  
Automatic Assessment ◽  
Evaluation Task ◽  
Point Data ◽  
Set Up

This paper mainly introduces the relevant contents of automatic assessment of upper limb mobility after stroke, including the relevant knowledge of clinical assessment of upper limb mobility, Kinect sensor to realize spatial location tracking of upper limb bone points, and GCRNN model construction process. Through the detailed analysis of all FMA evaluation items, a unique experimental data acquisition environment and evaluation tasks were set up, and the results of FMA prediction using bone point data of each evaluation task were obtained. Through different number and combination of tasks, the best coefficient of determination was achieved when task 1, task 2, and task 5 were simultaneously used as input for FMA prediction. At the same time, in order to verify the superior performance of the proposed method, a comparative experiment was set with LSTM, CNN, and other deep learning algorithms widely used. Conclusion. GCRNN was able to extract the motion features of the upper limb during the process of movement from the two dimensions of space and time and finally reached the best prediction performance with a coefficient of determination of 0.89.

scholarly journals ANALISIS PERBANDINGAN ALGORITMA SIMETRIS RIVEST CODE 5 DENGAN ALGORITMA SIMETRIS RIVEST CODE 6) (Studi Kasus : SMK Negeri Seluma)

2019 ◽  
Vol 4 (2) ◽  
Author(s):  
Rozali Toyib ◽  
Ardi Wijaya
Keyword(s):  
Execution Time ◽  
Hash Function ◽  
Storage Media ◽  
Encryption And Decryption ◽  
Secure Data ◽  
Computer Based ◽  
Message Digest ◽  
Set Up

Abstack: Data stored in storage media is often lost or opened by certain parties who are not responsible, so that it is very detrimental to the owner of the data, it is necessary to secure data so that the data can be locked so that it cannot be opened by irresponsible parties. The RC5 and RC6 algorithms are digestive massage algorithms or sometimes also known as the hash function which is an algorithm whose input is a message whose length is not certain, and produces an output message digest from its input message with exactly 128 bits in length. RC6 password is a protection for the user in securing data on a PC or computer. Based on the results of the conclusions taken: For the experiments carried out on the RC5 algorithm the execution time for the generation of keys (set-up key) is very fast, which is about 9-10 ns, a trial carried out on the RC6 algorithm execution time for the key generator (set up key ) faster than 10-11 ns. In the encryption and decryption process, the execution time depends on the size or size of the plaintext file. The larger the size of the plaintext file, the longer the execution time.Abstrak : Data yang tersimpan dalam media penyimpanan sering hilang atau dibuka oleh pihak-pihak tertentu yang tidak bertanggung jawab, sehinga merugikan sekali bagi pemilik data tersebut, untuk itu diperlukan suatu pengamanan data agar data tersebut dapat terkunci sehingga tidak dapat dibuka oleh pihak yang tidak bertanggung jawab.. Algoritma RC5 dan RC6 merupakan algoritma massage digest atau kadang juga dikenal dengan hash function yaitu suatu algoritma yang inputnya berupa sebuah pesan yang panjangnya tidak tertentu, dan menghasilkan keluaran sebuah message digest dari pesan inputnya dengan panjang tepat 128 bit. Password RC6 merupakan salah satu perlindungan kepada user dalam pengamanan data yang berada dalam sebuah Pc atau computer. Berdasarkan hasil pengujian diambil kesimpulan : Untuk uji coba yang dilakukan pada algoritma RC5 waktu eksekusi untuk pembangkitan kunci  (set up key) sangat cepat sekali yaitu sekitar  9-10 ns, uji coba yang dilakukan pada algoritma RC6 waktu eksekusi untuk pembangkit kunci (set up key) lebih cepat sekali yaitu 10-11 ns, Pada proses enkripsi dan dekripsi, waktu eksekusi tergantung dari besar atau kecilnya ukuran file plaintext.s emakin besar ukuran file plaintext maka semakin lama waktu eksekusinya.

ProtoLeaks: A Reliable and Protocol-Independent Network Covert Channel

2012 ◽  
pp. 119-133 ◽  
Author(s):  
Arne Swinnen ◽  
Raoul Strackx ◽  
Pieter Philippaerts ◽  
Frank Piessens
Keyword(s):  
Covert Channel ◽  
Network Covert Channel

scholarly journals A Survey of Key Technologies for Constructing Network Covert Channel

2020 ◽  
Vol 2020 ◽  
pp. 1-20
Author(s):  
Jing Tian ◽  
Gang Xiong ◽  
Zhen Li ◽  
Gaopeng Gou
Keyword(s):  
Communication Technology ◽  
Network Architecture ◽  
The Internet ◽  
Covert Channel ◽  
Free Access ◽  
Transmission Network ◽  
Information Channel ◽  
Covert Channels ◽  
Key Technologies ◽  
Network Covert Channel

In order to protect user privacy or guarantee free access to the Internet, the network covert channel has become a hot research topic. It refers to an information channel in which the messages are covertly transmitted under the network environment. In recent years, many new construction schemes of network covert channels are proposed. But at the same time, network covert channel has also received the attention of censors, leading to many attacks. The network covert channel refers to an information channel in which the messages are covertly transmitted under the network environment. Many users exploit the network covert channel to protect privacy or guarantee free access to the Internet. Previous construction schemes of the network covert channel are based on information steganography, which can be divided into CTCs and CSCs. In recent years, there are some covert channels constructed by changing the transmission network architecture. On the other side, some research work promises that the characteristics of emerging network may better fit the construction of the network covert channel. In addition, the covert channel can also be constructed by changing the transmission network architecture. The proxy and anonymity communication technology implement this construction scheme. In this paper, we divide the key technologies for constructing network covert channels into two aspects: communication content level (based on information steganography) and transmission network level (based on proxy and anonymity communication technology). We give an comprehensively summary about covert channels at each level. We also introduce work for the three new types of network covert channels (covert channels based on streaming media, covert channels based on blockchain, and covert channels based on IPv6). In addition, we present the attacks against the network covert channel, including elimination, limitation, and detection. Finally, the challenge and future research trend in this field are discussed.

scholarly journals A NEW AND ADAPTIVE SECURITY MODEL FOR PUBLIC COMMUNICATION BASED ON CORRELATION OF DATA FRAMES

2019 ◽  
Vol 59 (2) ◽  
pp. 126-133
Author(s):  
Haider Tarish Haider ◽  
Dhiaa Halboot Muhsen ◽  
Haider Ismael Shahadib ◽  
Ong Hang See
Keyword(s):  
Information Technologies ◽  
High Capacity ◽  
Data Communication ◽  
Superior Performance ◽  
Secret Message ◽  
Communication Model ◽  
Security Model ◽  
Secret Key ◽  
Proposed Model ◽  
Capacity Data

Recent developments in communication and information technologies, plus the emerging of the Internet of Things (IoT) and machine to machine (M2M) principles, create the need to protect data from multiple types of attacks. In this paper, a secure and high capacity data communication model is proposed to protect the transmitted data based on identical frames between a secret and cover data. In this model, the cover data does not convey any embedded data (as in normal steganography system) or modify the secret message (as in traditional cryptography techniques). Alternatively, the proposed model sends the positions of the cover frames that are identical with the secret frames to the receiver side in order to recover the secret message. One of the significant advantages of the proposed model is the size of the secret key message which is considerably larger than the cover size, it may be even hundred times larger. Accordingly, the experimental results demonstrate a superior performance in terms of the capacity rate as compared to the traditional steganography techniques. Moreover, it has an advantage in terms of the required bandwidth to send the data or the required memory for saving when compared to the steganography methods, which need a bandwidth or memory up to 3-5 times of the original secret message. Where the length of the secret key (positions of the identical frames) that should be sent to the receiver increases by only 25% from the original secret message. This model is suitable for applications with a high level of security, high capacity rate and less bandwidth of communication or low storage devices.

Dynamic soil parameters and Case damping for high-capacity long H-piles

2011 ◽  
Vol 48 (11) ◽  
pp. 1616-1629
Author(s):  
Arthur K.O. So ◽  
Charles W.W. Ng
Keyword(s):  
Load Transfer ◽  
High Capacity ◽  
Transfer Mechanism ◽  
Damping Factor ◽  
Viscous Damping ◽  
Soil Response ◽  
Pile Shaft ◽  
Load Transfer Mechanism ◽  
Set Up ◽  
Matching Techniques

Uncertainty exists in signal-matching techniques. The quake and damping obtained may not be the actual response of the soil. In this paper, the final sets, strain gauge readings, pile driving analyzer, and Case pile wave analysis program of 12 high-capacity long H-piles at the end of initial driving as well as two of them at restrike are studied. Measured and deduced data show that the soil response underneath the pile toes has limited movement and yielding despite the piles being set using very heavy hammer rams and large ram drops. The quake and damping decrease with increased shearing strain and shearing stress, but are influenced by pile whipping, rebounded stress wave, and load-transfer mechanism. The lumped Case damping factor decreases with increased side resistance to total resistance ratio. This factor can decrease or increase with time due to changes in the load-transfer mechanism after set-up, thus affecting the proportion of viscous damping of soil along the pile shaft and at the pile toe. A Case damping model is proposed that approximates the lumped Case damping factor as the sum of hysteretic damping of the pile and viscous damping of the surrounding soil. The effects of variation in load distribution and set-up along the pile shaft in layered soils and incomplete mobilization of soil at the pile toe on the Case damping factors are explained.

scholarly journals Block maps between primitive uniform and Pisot substitutions

2014 ◽  
Vol 35 (7) ◽  
pp. 2292-2310 ◽  
Author(s):  
VILLE SALO ◽  
ILKKA TÖRMÄ
Keyword(s):  
Finite Set ◽  
Set Up

In this article, we prove that for all pairs of primitive Pisot or uniform substitutions with the same dominating eigenvalue, there exists a finite set of block maps such that every block map between the corresponding subshifts is an element of this set, up to a shift.

Operator Support in Traffic Management: A Heuristics Model and Experimental Study

1996 ◽  
Vol 40 (18) ◽  
pp. 872-876
Author(s):  
John Murray ◽  
Yili Liu
Keyword(s):  
Traffic Management ◽  
Contextual Information ◽  
Information Modeling ◽  
Superior Performance ◽  
Traffic Information ◽  
Control Center ◽  
Modeling Process ◽  
Quantitative Data Analysis ◽  
Human Operators ◽  
Real Traffic

The identification of problems from numeric traffic measurements is an important part of control center activities in ATMS (Advanced Traffic Management Systems). However, an information modeling process that relies solely upon ‘traditional’ quantitative data analysis does not reflect faithfully the actual methods used by human operators. In addition to common-sense knowledge and specific contextual information, operators also use various heuristics and rules-of-thumb to supplement the numerical analysis. This paper describes an experiment to examine the effectiveness of an expert system that integrates quantitative and qualitative traffic information using a human-centered knowledge system design. The system's performance was investigated using a data suite of real traffic scenarios; the statistically significant results showed that the integrated process had superior performance compared to the ‘traditional’ quantitative analysis running alone.

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