The Topology of Foliations Formed by the Generic K-Orbits of a Subclass of the Indecomposable MD5-Groups

The present paper is a continuation of [13], [14] of the authors. Specifically, the paper considers the MD5-foliations associated to connected and simply connected MD5-groups such that their Lie algebras have 4-dimensional commutative derived ideal. In the paper, we give the topological classification of all considered MD5-foliations. A description of these foliations by certain fibrations or suitable actions of $\mathbb{R}^{2}$ and the Connes' C*-algebras of the foliations which come from fibrations are also given in the paper.

20 pages, no figure

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Komparasi Fungsi Hash Md5 Dan Sha256 Dalam Keamanan Gambar Dan Teks

Implementasi ilmu kriptografi menjadi semakin sering digunakan seiring dengan daruratnya keamanan data. Ilmukriptografi yang di dalamnya terdapat fungsi hash mengubah data menjadi sebuah nilai representasi agar data yang dimaksudtidak dapat dengan mudah diretas dan disalahgunakan oleh orang lain. Banyak macam fungsi hash yang dapat digunakan untukfungsi kriptografi di antaranya adalah MD5 dan SHA256. Dari hasil percobaan menunjukkan bahwa keduanya mampumengubah data menjadi nilai representatif dan tidak mudah dibaca oleh orang lain. Meskipun begitu, fungsi hash SHA256 lebihbaik dalam mengamankan data karena nilai representatif yang dihasilkan lebih rumit dibandingkan dengan MD5.

8 citations

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A Contribution to Secure the Routing Protocol "Greedy Perimeter Stateless Routing" Using a Symmetric Signature-Based AES and MD5 Hash

This work presents a contribution to secure the routing protocol GPSR (Greedy Perimeter Stateless Routing) for vehicular ad hoc networks, we examine the possible attacks against GPSR and security solutions proposed by different research teams working on ad hoc network security. Then, we propose a solution to secure GPSR packet by adding a digital signature based on symmetric cryptography generated using the AES algorithm and the MD5 hash function more suited to a mobile environment.

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Pengujian Integritas File Operasi Tanda Tangan Digital Menggunakan Kombinasi Hash MD5, RSA dan Skema Qr-Cod

Kebijakan WFH pada masa pandemi COVID-19 mengakibatkan berbagai dokumen yang awalnya masih menggunakan sistem manual beralih ke sistem digital termasuk pada pengesahan pada dokumen tersebut. Maka penerapan tanda tangan digital dapat dijadikan alternatif sebagai bukti autentik sebuah dokumen untuk menggantikan tanda tangan konvensional. Penelitian ini bertujuan untuk mengembangkan perangkat lunak guna melakukan pengujian integritas dokumen dengan tanda tangan digital yang dibangun menggunakan fungsi hash MD5 dan algoritma RSA yang kemudian di-generate menjadi Qr-Code pada dokumen yang terdiri dari 1000 kata dengan ekstensi .docx. Dokumen yang akan diuji tersebut diberikan tanda tangan digital dengan perangkat lunak yang dibangun dan selanjutnya dilakukan pengujian integritas dengan melakukan operasi modifikasi terhadap file teks tersebut. Pada penelitian ini telah dibuat perangkat lunak untuk menerapkan skema autentikasi pada sebuah dokumen. Dari hasil penelitian yang dilakukan maka dapat disimpulkan jika fung

3 citations

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The Geometry of K-Orbits of a Subclass of MD5-Groups and Foliations Formed by their Generic K-Orbits

The present paper is a continuation of Le Anh Vu's ones [13], [14], [15]. Specifically, the paper is concerned with the subclass of connected and simply connected MD5-groups such that their MD5-algebras $\mathcal{G}$ have the derived ideal ${\mathcal{G}}^{1} : = [ \mathcal{G},\mathcal{G} ]\equiv$ ${\bf{R}}^{3}$. We shall describe the geometry of K-orbits of these MD5-groups. The foliations formed by K-orbits of maximal dimension of these MD5-groups and their measurability are also presented in the paper.

24 pages, no figue

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A powerful heuristic method for generating efficient database systems

Heuristic functions are an integral part of MapReduce software, both in Apache Hadoop and Spark. If the heuristic function performs badly, the load in the reduce part will not be balanced and access times spike. To investigate this problem closer, we run an optimal database program with numerous different heuristic functions on database. We will leverage the Amazon elastic MapReduce framework. The paper investigates on general purpose, implementation, and evaluation of heuristic algorithm for generating optimal database system, checksum, and special heuristic functions. With the analysis, we present the corresponding runtime results. For the coding part, the records counting part is hasty and can only work for local Hadoop part, it can be debugged and optimized for general purpose implement on Hadoop and Spark and turn into an effective performance monitor tool. As mentioned before, there are strange issue, also the performance of BLAKE2s is unexpectedly slow in that it’s widely accepted the performance of BL

0 citations

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An Idea to Increase the Security of EAP-MD5 Protocol Against Dictionary Attack

IEEE 802.1X is an international standard for Port-based Network Access Control which provides authentication for devices applicant of either local network or wireless local network. This standard defines the packing of EAP protocol on IEEE 802. In this standard, authentication protocols become a complementary part of network security. There is a variety in EAP family protocols, regarding their speed and security. One of the fastest of these protocols is EAP-MD5 which is the main subject of this paper. Moreover, in order to improve EAP-MD5 security, a series of attacks against it have been investigated. In this paper at first EAP-MD5 protocol is introduced briefly and a series of the dictionary attacks against it are described. Then, based on observed weaknesses, by proposing an appropriate idea while maintaining the speed of execution, its security against dictionary attack is improved.

6 pages, 4 figures, 1 table, presented in 3rd International Conference on Combinatorics, Cryptography and Computation, December 15, 2018 in IUST, Iran

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Strategi Manajemen Kurikulum Merdeka: Studi Kasus di SMA Methodist Medan

Latar Belakang: Kurikulum Merdeka merupakan reformasi pendidikan yang memberikan keleluasaan kepada satuan pendidikan dalam merancang proses belajar yang kontekstual dan sesuai dengan kebutuhan peserta didik. Tujuan: Penelitian ini bertujuan untuk mengidentifikasi strategi manajemen yang diterapkan oleh sekolah dasar negeri dalam mengimplementasikan Kurikulum Merdeka. Metode: Penelitian ini menggunakan pendekatan kualitatif studi kasus di sebuah Sekolah Mengengah Atas Methodist Medan pengumpulan data melalui wawancara mendalam, observasi, dan dokumentasi. Hasil: Hasil menunjukkan bahwa keberhasilan implementasi Kurikulum Merdeka sangat dipengaruhi oleh perencanaan strategis kepala sekolah, kolaborasi guru, serta dukungan sarana dan pelatihan yang memadai. Kesimpulan: Manajemen kurikulum yang adaptif dan partisipatif menjadi kunci dalam menghadapi dinamika implementasi Kurikulum Merdeka.

0 citations

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Long-Horizon State Tracking in LLMs: Executing MD5 through a Deep Sequence of Dependent Tool Calls

Long-horizon tasks remain uncommon in large language model (LLM) evaluation, and for a reason: when each step depends on the last, per-step accuracy that looks excellent in isolation decays catastrophically, as errors cascade and the end-to-end failure probability grows sharply with length. Existing agentic benchmarks report end-to-end success but confound this state-tracking difficulty with instruction interpretation, give no control group that isolates it, and are vulnerable to shortcuts such as a hallucinated final answer, so they cannot say why a long run fails. Whether an LLM can carry exact intermediate state across many tool calls at all is itself not well established. We test this cleanly by having the model compute a cryptographic hash, MD5, step by step: a sequence of $196$ dependent tool calls over $64$ rounds while it carries four $32$-bit words $(a,b,c,d)$ in its own context from one call to the next. Interpretation is trivial and, because we implement MD5 from scratch (RFC~1321), we align every

6 Pages, 2 figures

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Optimizing the Performance of Clouds Using Hash Codes in Apache Hadoop and Spark

Hash functions are an integral part of MapReduce software, both in Apache Hadoop and Spark. If the hash function performs badly, the load in the reduced part will not be balanced and access times will spike. To investigate this problem further, we ran the Wordcount program with numerous different hash functions on Amazon AWS. In particular, we will leverage the Amazon Elastic MapReduce framework. The paper investigates the general purpose, cryptographic, checksum, and special hash functions. Through the analysis, we present the corresponding runtime results.

3 citations

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Nonsense Helps: Prompt Space Perturbation Broadens Reasoning Exploration

Reinforcement learning with verifiable rewards, particularly Group Relative Policy Optimization (GRPO), has significantly advanced the reasoning capabilities of Large Language Models (LLMs). However, in complex tasks, GRPO frequently suffers from the ``zero-advantage problem'': when all sampled rollouts for a query fail, the relative advantage collapses to zero. Consequently, the model loses effective training signals for these questions, wasting the training data and computational budget. While simply increasing the sampling budget for these questions is a common remedy, the static sampling policy inherently constrains reasoning exploration, limiting the success rate. In this paper, we propose Lorem Perturbation for Exploration (LoPE), a simple yet effective training framework to break this exploration bottleneck. We posit that task-irrelevant prompt-space perturbations can shift the model's output distribution enough to unlock orthogonal reasoning pathways for hard questions. Specifically, LoPE prepends seq

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10 Principles of Psychology You Can Use to Improve Your BMP to JPG tool

the array of web tools available today caters to a myriad of tasks and challenges. These tools, continually evolving, showcase humanity's resilience and creativity in harnessing the power of technology.

0 citations

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Who Benchmarks the Benchmarks? Towards Comprehensive Evaluation of Commonsense Reasoning Benchmarks

Commonsense reasoning is a key language model capability, as it is purportedly a prerequisite for many basic tasks, unlike specific factual knowledge. It is often measured with multiple-choice questions (MCQ) benchmarks, e.g. HellaSwag and PIQA. Some of these benchmarks, however, are outdated and contain numerous validity issues. We illustrate some typical validity issues with a case study on HellaSwag, one of the most popular and problematic benchmarks for commonsense reasoning. The issues we find range from basic ungrammaticality and numerous typos to misleading prompts or equally correct options. We show that if we remove question prompts or replace them with "Lorem ipsum dolor...", about 68% of model predictions do not change. We argue that this occurs due to inner flaws in the benchmark, not mere contamination that might be present in some models. Since benchmark scores are an essential part of model selection in both research and commercial applications, these issues can have severe consequences. Based

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How to Outsmart Your Boss on Ascii converter tool

the array of web tools available today caters to a myriad of tasks and challenges. These tools, continually evolving, showcase humanity's resilience and creativity in harnessing the power of technology.

0 citations

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Inverting Cryptographic Hash Functions via Cube-and-Conquer

MD4 and MD5 are fundamental cryptographic hash functions proposed in the early 1990s. MD4 consists of 48 steps and produces a 128-bit hash given a message of arbitrary finite size. MD5 is a more secure 64-step extension of MD4. Both MD4 and MD5 are vulnerable to practical collision attacks, yet it is still not realistic to invert them, i.e., to find a message given a hash. In 2007, the 39-step version of MD4 was inverted by reducing to SAT and applying a CDCL solver along with the so-called Dobbertin's constraints. As for MD5, in 2012 its 28-step version was inverted via a CDCL solver for one specified hash without adding any extra constraints. In this study, Cube-and-Conquer (a combination of CDCL and lookahead) is applied to invert step-reduced versions of MD4 and MD5. For this purpose, two algorithms are proposed. The first one generates inverse problems for MD4 by gradually modifying the Dobbertin's constraints. The second algorithm tries the cubing phase of Cube-and-Conquer with different cutoff threshol

41 pages, 11 figures. A revised version accepted to JAIR

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Implementasi Steganografi Pada Citra Digital Menggunakan Metode Least Significant Bit Dengan Kriptografi Super Enkripsi

Super Enkripsi merupakan salah satuh satu teknik kriptografi dengan menggabungkan dua atau lebih dari satu algoritma cipher dengan tujuan untuk menciptakan cipher text yang lebih kuat. Kriptografi sendiri umumnya merupakan suatu teknik untuk mengubah pesan menjadi kode - kode acak agar tidak diketahui pihak lain yang tidak diinginkan. kriptografi memiliki berbagai macam bentuk metode dan algoritma, dua diantaranya adalah Algoritma vigenere cipher dan Advanced Encryption Standard (AES). Pesan yang berupa teks dapat di enkripsi menggunakan key atau kunci dengan menggunakan teknik super enkripsi dari gabungan vigenere cipher dan algoritma Advanced Encryption Standard (AES). Steganografi merupakan suatu teknik untuk menyembunyikan informasi atau data pada suatu media atau berkas. Steganografi juga memiliki beberapa metode algoritma yang dapat diimplementasikan dalam prosesnya, salah satunnya yaitu metode Least Significant Bit (LSB). Penelitian ini bertujuan untuk membuat suatu program atau aplikasi yang dapat men

0 citations

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Seeing Is Not Always Believing: Invisible Collision Attack and Defence on Pre-Trained Models

Large-scale pre-trained models (PTMs) such as BERT and GPT have achieved great success in diverse fields. The typical paradigm is to pre-train a big deep learning model on large-scale data sets, and then fine-tune the model on small task-specific data sets for downstream tasks. Although PTMs have rapidly progressed with wide real-world applications, they also pose significant risks of potential attacks. Existing backdoor attacks or data poisoning methods often build up the assumption that the attacker invades the computers of victims or accesses the target data, which is challenging in real-world scenarios. In this paper, we propose a novel framework for an invisible attack on PTMs with enhanced MD5 collision. The key idea is to generate two equal-size models with the same MD5 checksum by leveraging the MD5 chosen-prefix collision. Afterwards, the two ``same" models will be deployed on public websites to induce victims to download the poisoned model. Unlike conventional attacks on deep learning models, this n

10 pages, 4 figures

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An Analysis of Conti Ransomware Leaked Source Codes

In recent years, there has been an increase in ransomware attacks worldwide. These attacks aim to lock victims’ machines or encrypt their files for ransom. These kinds of ransomware differ in their implementation and techniques, starting from how they spread, vulnerabilities they leverage, methods to hide their behaviors from antivirus software, encryption methods, and performance. The Conti ransomware is sophisticated ransomware that operates as ransomware-as-a-service. It started in 2019 and had an unprecedented human impact by targeting healthcare systems and cost $45 million. This paper analyzes the Conti ransomware source codes leaked on February 27, 2022, by an anonymous individual. We first look at the general code structure. Then, we analyze its flow, starting with its application programming interface disguise techniques, anti hook mechanisms, command-line arguments, and finally, its multithreaded encryption. We also perform a static and dynamic analysis of the latest known Conti sample in an isolate

61 citations

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Learning Long-Range Representations with Equivariant Messages

Machine learning interatomic potentials trained on first-principles reference data are becoming valuable tools for computational physics, biology, and chemistry. Equivariant message-passing neural networks, including transformers, achieve state-of-the-art accuracy but rely on cutoff-based graphs, limiting their ability to capture long-range effects such as electrostatics or dispersion, as well as electron delocalization. While long-range correction schemes based on inverse power laws of interatomic distances have been proposed, they are unable to communicate higher-order geometric information and are thus limited in applicability. To address this shortcoming, we propose the use of equivariant, rather than scalar, charges for long-range interactions, and design a graph neural network architecture, LOREM, around this long-range message passing mechanism. We consider several datasets specifically designed to highlight non-local physical effects, and compare short-range message passing with different receptive fi

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Transclusions in an HTML-Based Environment

Transclusions are an advanced technique for the inclusion of existing content into new documents without the need to duplicate it. Although originally described in the early 1960s, transclusions have still not been made available to users and authors on the world wide web. This paper describes the prototype implementation of a system that allows users to write articles that may contain transclusions. The system offers a simple web-based interface where users can compose new articles. With a simple button the user has the ability to insert a transclusion from any HTML page available on the world wide web. While other approaches introduce new markups for the HTML specification, make use of technologies such as XML and XLink or employ authoring systems that internally support transclusions and can generate web pages as output, this implementation solely relies on the techniques provided by an HTML-based environment. Therefore HTML, Javascript, the Document Object Model, CGI scripts and HTTP are the core technolo

24 citations

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