arXiv subjects

Muhammad Waseem

Publications and source records attributed to Muhammad Waseem.

89 records · Page 5Linked to original sources

arXiv2022

Decision Models for Selecting Patterns and Strategies in Microservices Systems and their Evaluation by Practitioners

Researchers and practitioners have recently proposed many Microservices Architecture (MSA) patterns and strategies covering various aspects of microservices system life cycle, such as service design and security. However, selecting and implementing these patterns and strategies can entail various challenges for microservices practitioners. To this end, this study proposes decision models for selecting patterns and strategies covering four MSA design areas: application decomposition into microservices, microservices security, microservices communication, and service discovery. We used peer-reviewed and grey literature to identify the patterns, strategies, and quality attributes for creating these decision models. To evaluate the familiarity, understandability, completeness, and usefulness of the decision models, we conducted semi-structured interviews with 24 microservices practitioners from 12 countries across five continents. Our evaluation results show that the practitioners found the decision models as an effective guide to select microservices patterns and strategies.

cs.SE↗

arXiv2021

A Decision Model for Selecting Patterns and Strategies to Decompose Applications into Microservices

Microservices Architecture (MSA) style is a promising design approach to develop software applications consisting of multiple small and independently deployable services. Over the past few years, researchers and practitioners have proposed many MSA patterns and strategies covering various aspects of microservices design, such as application decomposition. However, selecting appropriate patterns and strategies can entail various challenges for practitioners. To this end, this study proposes a decision model for selecting patterns and strategies to decompose applications into microservices. We used peer-reviewed and grey literature to collect the patterns, strategies, and quality attributes for creating this decision model.

cs.SE↗

arXiv2021

Ethics of AI: A Systematic Literature Review of Principles and Challenges

Ethics in AI becomes a global topic of interest for both policymakers and academic researchers. In the last few years, various research organizations, lawyers, think tankers and regulatory bodies get involved in developing AI ethics guidelines and principles. However, there is still debate about the implications of these principles. We conducted a systematic literature review (SLR) study to investigate the agreement on the significance of AI principles and identify the challenging factors that could negatively impact the adoption of AI ethics principles. The results reveal that the global convergence set consists of 22 ethical principles and 15 challenges. Transparency, privacy, accountability and fairness are identified as the most common AI ethics principles. Similarly, lack of ethical knowledge and vague principles are reported as the significant challenges for considering ethics in AI. The findings of this study are the preliminary inputs for proposing a maturity model that assess the ethical capabilities of AI systems and provide best practices for further improvements.

cs.CY↗

arXiv2021

Design, Monitoring, and Testing of Microservices Systems: The Practitioners' Perspective

Context: Microservices Architecture (MSA) has received significant attention in the software industry. However, little empirical evidence exists on design, monitoring, and testing of microservices systems. Objective: This research aims to gain a deep understanding of how microservices systems are designed, monitored, and tested in the industry. Method: A mixed-methods study was conducted with 106 survey responses and 6 interviews from microservices practitioners. Results: The main findings are: (1) a combination of domain-driven design and business capability is the most used strategy to decompose an application into microservices, (2) over half of the participants used architecture evaluation and architecture implementation when designing microservices systems, (3) API gateway and Backend for frontend patterns are the most used MSA patterns, (4) resource usage and load balancing as monitoring metrics, log management and exception tracking as monitoring practices are widely used, (5) unit and end-to-end testing are the most used testing strategies, and (6) the complexity of microservices systems poses challenges for their design, monitoring, and testing, for which there are no dedicated solutions. Conclusions: Our findings reveal that more research is needed to (1) deal with microservices complexity at the design level, (2) handle security in microservices systems, and (3) address the monitoring and testing challenges through dedicated solutions.

cs.SE↗

arXiv2021

Automated Identification of Security Discussions in Microservices Systems: Industrial Surveys and Experiments

Lack of awareness and knowledge of microservices-specific security challenges and solutions often leads to ill-informed security decisions in microservices system development. We claim that identifying and leveraging security discussions scattered in existing microservices systems can partially close this gap. We define security discussion as "a paragraph from developer discussions that includes design decisions, challenges, or solutions relating to security". We first surveyed 67 practitioners and found that securing microservices systems is a unique challenge and that having access to security discussions is useful for making security decisions. The survey also confirms the usefulness of potential tools that can automatically identify such security discussions. We developed fifteen machine/deep learning models to automatically identify security discussions. We applied these models on a manually constructed dataset consisting of 4,813 security discussions and 12,464 non-security discussions. We found that all the models can effectively identify security discussions: an average precision of 84.86%, recall of 72.80%, F1-score of 77.89%, AUC of 83.75% and G-mean 82.77%. DeepM1, a deep learning model, performs the best, achieving above 84% in all metrics and significantly outperforms three baselines. Finally, the practitioners' feedback collected from a validation survey reveals that security discussions identified by DeepM1 have promising applications in practice.

cs.SE↗

arXiv2021

Decomposing Convexified Security-Constrained ACOPF Problem with AGC Reformulation

This paper presents a reformulation for the automatic generation control (AGC) in a decomposed convex relaxation algorithm. It finds an optimal solution to the AC optimal power flow (ACOPF) problem that is secure against a large set of contingencies. The original ACOPF problem which represents the system without contingency constraints, is convexified by applying the second-order cone relaxation method. The contingencies are filtered to distinguish those that will be treated with preventive actions from those that will be left for corrective actions. The selected contingencies for preventive action are included in the set of security constraints. Benders decomposition is employed to decompose the convexified Security-Constrained ACOPF problem into a master problem and several security check sub-problems. Sub-problems are evaluated in a parallel computing process with enhanced computational efficiency. AGC within each sub-problem is modeled by a set of proposed valid constraints, so the procured solution is the physical response of each generation unit during a contingency. Benders optimality cuts are generated for the sub-problems having mismatches and the cuts are passed to the master problem to encounter the security-constraints. The accuracy of the relaxation results is verified using the presented tightness measure. The effectiveness of the presented valid AGC constraints and scalability of the proposed algorithm is demonstrated in several case studies.

math.OC↗

arXiv2021

On the Nature of Issues in Five Open Source Microservices Systems: An Empirical Study

Due to its enormous benefits, the research and industry communities have shown an increasing interest in the Microservices Architecture (MSA) style over the last few years. Despite this, there is a limited evidence-based and thorough understanding of the types of issues (e.g., faults, errors, failures, mistakes) faced by microservices system developers and causes that trigger the issues. Such evidence-based understanding of issues and causes is vital for long-term, impactful, and quality research and practice in the MSA style. To that end, we conducted an empirical study on 1,345 issue discussions extracted from five open source microservices systems hosted on GitHub. Our analysis led to the first of its kind taxonomy of the types of issues in open source microservices systems, informing that the problems originating from Technical debt (321, 23.86%), Build (145, 10.78%), Security (137, 10.18%), and Service execution and communication (119, 8.84%) are prominent. We identified that "General programming errors", "Poor security management", "Invalid configuration and communication", and "Legacy versions, compatibility and dependency" are the predominant causes for the leading four issue categories. Study results streamline a taxonomy of issues, their mapping with underlying causes, and present empirical findings that could facilitate research and development on emerging and next-generation microservices systems.

cs.SE↗

arXiv2020

A Systematic Mapping Study on Microservices Architecture in DevOps

Context: Applying Microservices Architecture (MSA) in DevOps has received significant attention in recent years. However, there exists no comprehensive review of the state of research on this topic. Objective: This work aims to systematically identify, analyze, and classify the literature on MSA in DevOps. Method: A Systematic Mapping Study (SMS) has been conducted on the literature published between January 2009 and July 2018. Results: Forty-seven studies were finally selected and the key results are: (1) Three themes on the research on MSA in DevOps are "microservices development and operations in DevOps", "approaches and tool support for MSA based systems in DevOps", and "MSA migration experiences in DevOps". (2) 24 problems with their solutions regarding implementing MSA in DevOps are identified. (3) MSA is mainly described by using boxes and lines. (4) Most of the quality attributes are positively affected when employing MSA in DevOps. (5) 50 tools that support building MSA based systems in DevOps are collected. (6) The combination of MSA and DevOps has been applied in a wide range of application domains. Conclusions: The results and findings will benefit researchers and practitioners to conduct further research and bring more dedicated solutions for the issues of MSA in DevOps.

cs.SE↗

arXiv2020

Dynamics and multiqubit entanglement in distant resonators

We consider the dynamics of the photon states in distant resonators coupled to a common bus resonator at different positions. The frequencies of distant resonators from a common bus resonator are equally detuned. These frequency detunings are kept larger than the coupling strengths of each resonator to the common bus resonator to satisfy the dispersive interaction regime. In the dispersive regime, we show that the time dynamics of the system evolve to an arbitrary W-type state in a single step at various interaction times. Our results show that a one-step generation of arbitrary W-type states can be achieved with high fidelity in a system of superconducting resonators.

quant-ph↗

arXiv2019

Quantitative analysis of $p$-wave three-body losses via cascade process

We describe the three-body loss coefficient of identical fermions with $p$-wave interactions using a set of rate equations in which three-body recombination happens via an indirect process. Our theoretical treatment explains experimental results just above the universal scaling law regime of weak interactions. Furthermore, we theoretically extend and experimentally verify the rate equation model for the case of atoms trapped in two dimensions. Moreover, we find that the three-body loss coefficient in a two-dimensional trap is proportional to $A_{p}^{3}$ in the weakly interacting regime, where $A_{p}$ is the scattering area. Our results are useful in understanding three-body physics with $p$-wave interactions.

cond-mat.quant-gas↗

arXiv2018

Unitarity-limited behavior of three-body collisions in a p-wave interacting Fermi gas

We experimentally investigate the unitarity-limited behavior of the three-body loss near a p-wave Feshbach resonance in a single-component Fermi gas of $^6$Li atoms. At the unitarity limit, the three-body loss coefficient $L_{3}$ exhibits universality in the sense that it is independent of the interaction strength and follows the predicted temperature scaling law of $L_3 \propto T^{-2}$. When decreasing the interaction strength from the unitarity regime, the three-body loss coefficient as a function of the interaction strength and temperature can be described by the theory based on the association of an excited resonant quasibound state and its relaxation into a deep stable dimer by collision with a third atom in the framework of the standard Breit-Wigner theoretical approach. The results reported here are important to understand the properties of a resonant p-wave Fermi gas in the prospect of quantum few- and many-body physics.

cond-mat.quant-gas↗

arXiv2018

Scaling Law for Three-body Collisions in Identical Fermions with $p$-wave Interactions

We experimentally confirmed the threshold behavior and scattering length scaling law of the three-body loss coefficients in an ultracold spin-polarized gas of $^6$Li atoms near a $p$-wave Feshbach resonance. We measured the three-body loss coefficients as functions of temperature and scattering volume, and found that the threshold law and the scattering length scaling law hold in limited temperature and magnetic field regions. We also found that the breakdown of the scaling laws is due to the emergence of the effective-range term. This work is an important first step toward full understanding of the loss of identical fermions with $p$-wave interactions.

cond-mat.quant-gas↗

arXiv2017

Two-body relaxation in a Fermi gas at a p-wave Feshbach resonance

We systematically studied the two-body loss in a two-component Fermi gas of $^6$Li atoms near a p-wave Feshbach resonance. The two-body loss rate constants were measured for various temperatures and magnetic fields using atoms trapped in three-dimensional and quasi-two-dimensional traps. Our results were nicely reproduced by a theoretical model that incorporates the two-body loss as an imaginary part to the inverse of the scattering volume in the scattering amplitude expression. The observed loss suppression in quasi-two-dimensional traps may provide a promising strategy to realize a p-wave superfluid in a system of ultracold atoms.

cond-mat.quant-gas↗

arXiv2016

Creation of p-wave Feshbach molecules in the selected angular momentum states using an optical lattice

We selectively create p-wave Feshbach molecules in the $m_{l}=\pm 1$ orbital angular momentum projection state of $^{6}$Li. We use an optical lattice potential to restrict the relative momentum of the atoms such that only the $m_{l}=\pm 1$ molecular state couples to the atoms at the Feshbach resonance. We observe the hollow-centered dissociation profile, which is a clear indication of the selective creation of p-wave molecules in the $m_{l}=\pm1$ states. We also measure the dissociation energy of the p-wave molecules created in the optical lattice and develop a theoretical formulation to explain the dissociation energy as a function of the magnetic field ramp rate for dissociation. The capability of selecting one of the two closely-residing p-wave Feshbach resonances is useful for the precise characterization of the p-wave Feshbach resonances.

cond-mat.quant-gas↗

arXiv2015

Realization of quantum gates with multiple control qubits or multiple target qubits in a cavity

In this paper, we propose a scheme to realize three-qubit controlled phase gate and multiqubit controlled-NOT gate of one qubit simultaneously controlling n target qubit with four level quantum system in a cavity. Adjustment of level spacing during the gates implementation is not required. Implementation time for multiqubit controlled NOT gate is independent of number of qubit. Three-qubit phase gate is generalized to n-qubit phase gate with multiple control qubit and the number of steps (complexity) reduces linearly as compare to conventional gate decomposition method. Our scheme can be applied to various types of physical systems such as superconducting qubits coupled to resonator and trapped atoms in a cavity. Experimental possibility of our approach is also presented.

quant-ph↗

arXiv2013

Three qubit Grover's algorithm using superconducting quantum interference devices in cavity QED

We present a scheme for the implementation of three qubit Grover's algorithm using four-level superconducting quantum interference devices (SQUIDs) coupled to a superconducting resonator. The scheme is based on resonant, off-resonant interaction of the cavity field with SQUIDs and the application of classical microwave pulses. We show that adjustment of SQUID level spacing during the gate operations, adiabatic passage, and second-order detuning are not required that leads to faster implementation. We also show that the marked state can be searched with high fidelity even in the presence of level decay and cavity dissipation.

quant-ph↗

arXiv2012

Multiqubit quantum phase gate using four-level superconducting quantum interference devices coupled to superconducting resonator

In this paper, we propose a scheme to realize three-qubit quantum phase gate of one qubit simultaneously controlling two target qubits using four-level superconducting quantum interference devices (SQUIDs) coupled to a superconducting resonator. The two lowest levels |0> and |1> of each SQUID are used to represent logical states while the higher energy levels |2> and |3> are utilized for gate realization. Our scheme does not require adiabatic passage, second order detuning, and the adjustment of the level spacing during gate operation which reduce the gate time significantly. The scheme is generalized for an arbitrary n-qubit quantum phase gate. We also apply the scheme to implement three-qubit quantum Fourier transform. key words: quantum phase gate, superconducting quantum interference devices (SQUIDs), superconducting resonator, quantum Fourier transform

quant-ph↗