and career path that can help you find the school that's right for you. Not sure what college you want to attend yet? 3 . a) public b) private c) hybrid d) all of the mentioned 6. 14, November 2020. To unlock this lesson you must be a Study.com Member. Cloud deployment models indicate how the cloud services are made available to users. Cloud computing enables convenient, on-demand network access to a shared pool of computing resources. A person, organization, or entity responsible for making a service available to interested parties. 5 . Try refreshing the page, or contact customer support. The purpose of this study was to develop a Deep Convective Cloud Reference Model to increase the capabilities of the current vicarious calibration system for reflective solar bands. Create your account. Last month, the IAM team created a Cloud Development Reference Model describing the key infrastructure components required for cloud adoption. Usage Scenario 1: A cloud consumer may request service from a cloud broker instead of contacting a cloud provider directly. It not only defines the domain but also sets taxonomy and drives coherency of approach amongst the many authors who contribute to the Private Cloud Reference Architecture documentation set. The four deployment models associated with cloud computing are as follows: • Public cloud As the name suggests, this type of cloud deployment model supports all users who want to make use of a computing resource, such as hardware (OS, CPU, memory, storage) or software (application server, database) on … The details will be discussed in the following sections and presented in increasing level of details in successive diagrams. var d = document.getElementById("menu-item-8"); 1 1 . INTRODUCTION Proposed system will be a free service that will let you bring all your photos, docs, and videos anywhere. Deployment Model: refers to the management of the cloud's infrastructure. NIST took an early leadership role in standardizing the definitions around cloud com… Business Support Services provide the business-related capabilities needed to simplify and support the end-to-end business activities of an enterprise Cloud Ecosystem. Create an account to start this course today. There are three type of cloud computing refrence model which are Infrastructure as a Service (IaaS), Platform as a Service (PaaS) and Software as a Services (SaaS). 11/4/2020; 2 minutes to read; In this article. Figure 3 Usage Scenario for Cloud Brokers. In this case, the provider may specify its requirements on capability, flexibility and functionality in SLA2 in order to provide essential requirements in SLA1. Standards bodies define the cloud reference models and then vendors map their services to these models. The following standard services will reduce complexity and simplify the enterprise business operations. Figure 1 – IBM Cloud Computing Reference Model We recently spent a day with IBM discussing its Cloud Computing approach. The cloud landscape has many vendors and multiple definitions of offerings, making it very difficult to evaluate their services. 10 . These cloud architecture posters give you information about Microsoft cloud services, including Microsoft 365, Azure Active Directory (Azure AD), Microsoft Intune, Microsoft Dynamics 365, and hybrid on-premises and cloud solutions. Cloud Reference Model , The Cloud Reference Model is an abstract description ,for layered IT architecture design. Developing deep convective cloud reference model for vicarious calibration. Visit the Introduction to Cloud Computing page to learn more. All other trademarks and copyrights are the property of their respective owners. Study.com has thousands of articles about every It allows rapid development and release of your services with minimal management effort or any other service provider interaction. Enrolling in a course lets you earn progress by passing quizzes and exams. Did you know… We have over 220 college It also serves as the foundation for other disruptive trends, including the Internet of Things, artificial intelligence (AI) and the digital business. Table 1 briefly lists the actors defined in the NIST cloud computing reference architecture. Cloud reference model framework Download PDF Info Publication number US20110252420A1. - Definition & Types, How to Network Virtual Machines in VirtualBox, What is Parallel Computing? The cloud reference model provides a fundamental reference point for the development of cloud computing. Each actor is an entity (a person or an organization) that participates in a transaction or process and/or performs tasks in cloud computing. Select a subject to preview related courses: The NIST definition for cloud computing is relatively complex, but quite straightforward. The Cloud Reference Model brings order to this cloud confusing cloud computing model. Fashion Model: Job Description & Career Information, Become a Hair Model: Step-by-Step Career Guide, High School Teacher, Role Model and Youth Advocate: Study.com Speaks with Anthony Curtis, Both a Student and a Parent: Studying Alongside Your Kids, Teacher Accountability Measures Become Law in Illinois, What You Should Know Before Applying to Law School, Schools with Automatic Transmission Training Programs: How to Choose, Why Your Degree Program Should Be More Like The Biggest Loser, Computational Chemistry Careers: Job Options and Requirements, Software Engineering Graduate Degree Program Options, How to Become a Certified Administrative Professional, Production Operator: Job Description, Duties and Requirements, Education-Portalcom Peoples Choice Awards Nominees, Become a Beauty Therapist Step-by-Step Career Guide, Should I Become a Special Education Teacher - Quiz Self-assessment Test, Talking Shop A Retail Store Transforms a College Curriculum, The Cloud Reference Model: Definition & Overview, Information Systems and Computer Applications: Certificate Program, CLEP Information Systems: Study Guide & Test Prep, Advanced Excel Training: Help & Tutorials, Microsoft Excel Certification: Practice & Study Guide, MTTC Computer Science (050): Practice & Study Guide, Computer Science 306: Computer Architecture, Computer Science 302: Systems Analysis & Design, Computer Science 201: Data Structures & Algorithms, Computer Science 106: Introduction to Linux, Computer Science 107: Database Fundamentals, Computer Science 204: Database Programming, Computer Science 202: Network and System Security, Time Multiplexing: Applications, Advantages & Examples, What is LTE? Get the unbiased info you need to find the right school. The Cloud Reference Model is a framework used by customers and vendors to define best practices for cloud computing. just create an account. a) The use of the word “cloud” makes reference to the two essential concepts b) Cloud computing abstracts systems by pooling and sharing resources c) cloud computing is nothing more than the Internet d) All of the mentioned 5. This of fers a … This means that any file you save to your virtual drive will Usage Scenario 2: Cloud carriers provide the connectivity and transport of cloud services from cloud providers to cloud consumers. The cornerstone of the Reference Architecture for Private Cloud materials is the Reference Model. Figure 1 – The Conceptual Reference Model. Security Reference Architecture 7 . This Reference Model forms the basis, or cornerstone, for all Reference Architecture in a Private Cloud. An error occurred trying to load this video. It can guide technology identification, classification, adoption, research and development processes for cloud-native application and for vendor lock-in aware enterprise architecture engineering methodologies. The Cloud Reference Model brings order to this cloud landscape. A person or organization that maintains a business relationship with, and uses service from, Cloud Providers. Services. In this lesson, you will learn about the principal actors, activities, and functions defined by the cloud reference model. An intermediary that provides connectivity and transport of cloud services from Cloud Providers to Cloud Consumers. - Uses & Definition, What Is a Virtual Private Network (VPN)? lessons in math, English, science, history, and more. US20110252420A1 US13/071,452 US201113071452A US2011252420A1 US 20110252420 A1 US20110252420 A1 US 20110252420A1 US 201113071452 A US201113071452 A US 201113071452A US 2011252420 A1 US2011252420 A1 US 2011252420A1 Authority US United States The cloud broker may create a new service by combining multiple services or by enhancing an existing service. You can test out of the The reference model defines five main actors: the cloud consumer, cloud provider, cloud auditor, cloud broker, and cloud carrier. courses that prepare you to earn The cloud hosting deployment model designates the cloud environment's exact category, its size, and the accessing mechanism. Each actor is an entity (a person or an organization) that participates in a transaction or process and/or performs tasks in cloud computing. IBM, Microsoft, Oracle, and Amazon are leading companies in the market, which provide cloud service that comply with the NIST reference model. The cloud carrier provides connectivity and transport of cloud services from the cloud providers to the cloud consumers. This figure appearing here, depicts the NIST high-level model or architecture, which defines the requirements, uses, characteristics, and standards of cloud computing: Get access risk-free for 30 days, A cloud auditor conducts independent assessments of the operation and security of the cloud services. Abstract: The cloud landscape is confusing -- with over 85 "cloud" vendors and various definitions of offerings it is difficult to evaluate services. Cloud Computing Architecture - Cloud Computing architecture comprises of many cloud components, which are loosely coupled. Cloud Computing offers online development and deployment tools, programming runtime environment through PaaS model. Figure 4 Usage Scenario for Cloud Carriers. This figure appearing here also illustrates various cloud providers and their technologies within the available cloud service models in the market. Last Updated. first two years of college and save thousands off your degree. This allows companies to improve scalability, agility, increase innovation and reduce costs. The Model divides cloud-based application architecture into seven layers: Application, Transformation, Control, Instantiation, Appliance, Virtual, and Physical. Anyone can earn Microsoft cloud for enterprise architects illustrations. NIST took an early leadership role in standardizing the definitions around cloud computing. Cloud computing continues to evolve from a market disruptor to the expected approach for IT. The reference model can be used for codifying cloud technologies. To achieve the potential of cloud computing, there is a need to have a standard cloud reference model for the software architects, software engineers, security experts and businesses, since it provides a fundamental reference point for the development of cloud computing. | Differentiated Instruction Resources, PLACE Business Education: Practice & Study Guide, Developing Strategic Thinking in Business, Common Core Math Grade 6 - The Number System: Standards, Praxis Biology & General Science: Plant Characteristics, Structures and Nutrients, Quiz & Worksheet - Mozart's The Magic Flute, Quiz & Worksheet - Properties of Similar Triangles, Quiz & Worksheet - Environmental Determinism, School Closures in Georgia Due to Coronavirus: Online Learning Options, Tech and Engineering - Questions & Answers, Health and Medicine - Questions & Answers, Working Scholars® Bringing Tuition-Free College to the Community, The customer of the cloud provider's services, Responsible for making cloud services available to interested parties, Conducts an independent assessment of cloud services, Manages the use, performance, and delivery of cloud services, and negotiates the relationship between the consumer and the provider, Provides connectivity and transport of services from providers to consumers, Provides a shared vision, understanding, and taxonomy, Reduces complexity to enhance the development of new products, Provides a guide for interoperability and standards, Provides a model for functions and services of cloud implementations. Standards bodies define the cloud reference models, and then vendors map their services to these models. The cloud broker may create a new service or enhance an existing service. Its essential characteristics include: Regarding the NIST cloud reference model, the five major actors of the model include: This figure appearing here actually shows the services between the actors in the reference model: A cloud consumer may request service from a broker instead or directly from a provider. flashcard set{{course.flashcardSetCoun > 1 ? Business Support Services ABBs of the Cloud Ecosystem Reference Model Cloud computing conceptual reference model identifies the major actors, their activities and functions in cloud computing. Vendors then develop their cloud platform while following the defined standard guidelines and start their operational engagement with enterprise business systems. Figure 2 illustrates the interactions among the actors. He has a Science Degree (Computer Science/Information Technology). | {{course.flashcardSetCount}} The Cloud Reference Model brings order to this cloud landscape. It now impacts every aspect of modern businesses. - Definition & Concept, Cloud Database Services: Features & Providers, Cloud Runtime & Framework Services: Features & Providers, Cloud Content Delivery Network Services: Features & Providers, Cloud Analytics Services: Features & Providers, Cloud-Based High Performance Computing (HPC) Applications: Purpose & Examples, Biological and Biomedical The Model divides cloud-based application architecture into seven layers: Application, Transformation, Control, Instantiation, Appliance, Virtual, and Physical. 4 . A cloud auditor conducts independent audits and may contact the others to collect necessary information. - Definition & Examples, What is a Color Model? - Design, Types & Example, Learning Agents: Definition, Components & Examples, Five Basic Concepts of Object-Oriented Design, What is a VLAN? - Performance & Examples, What is a Data Mart? A layer is a set of IT ,functions that deliver concep,tually similar services within ,part of the overall architecture. As illustrated in Figure 4, a cloud provider participates in and arranges for two unique service level agreements (SLAs), one with a cloud carrier (e.g. Alright, let's take a moment to review what we've learned. The National Institute of Standards and Technology (NIST), a US Government body, defines the standard protocol for cloud computing providers. - Systems & Applications, IT Requirements Documents: Definition, Templates & Examples, Quiz & Worksheet - Inserting Headers & Footers in Excel, Quiz & Worksheet - Inserting Watermarks in an Excel Worksheet, Quiz & Worksheet - Customizing the Quick Access Toolbar in Excel, Quiz & Worksheet - How to Use the Data Validation in Excel, Quiz & Worksheet - How to Adjust Column Width & Row Height in Excel, Hardware and Systems Technology: Tutoring Solution, Internet, Intranet, and Extranet: Tutoring Solution, CPA Subtest IV - Regulation (REG): Study Guide & Practice, CPA Subtest III - Financial Accounting & Reporting (FAR): Study Guide & Practice, ANCC Family Nurse Practitioner: Study Guide & Practice, Advantages of Self-Paced Distance Learning, Advantages of Distance Learning Compared to Face-to-Face Learning, Top 50 K-12 School Districts for Teachers in Georgia, Finding Good Online Homeschool Programs for the 2020-2021 School Year, Coronavirus Safety Tips for Students Headed Back to School, Hassan in The Kite Runner: Description & Character Analysis, Self-Care for Mental Health Professionals: Importance & Strategies, Soraya in The Kite Runner: Description & Character Analysis, The Pit and the Pendulum: Theme & Symbolism, Quiz & Worksheet - Physiology of Language & Speech, Quiz & Worksheet - Analyzing the Declaration of Independence, Quiz & Worksheet - Data Modeling in Software Engineering, Quiz & Worksheet - Conductivity of Aluminum Foil, Flashcards - Real Estate Marketing Basics, Flashcards - Promotional Marketing in Real Estate, What is Differentiated Instruction? In this example, the actual cloud providers are invisible to the cloud consumer and the cloud consumer interacts directly with the cloud broker. A cloud consumer may request cloud services from a cloud provider directly or via a cloud broker. The cloud computing reference model is an abstract model that characterizes and standardizes the functions of a cloud computing environment by partitioning it … It also tells the nature and purpose of the cloud. Type Of Cloud Computing Reference Model. Vendors then develop their cloud platform while following the defined standard guidelines and starting their operational engagement with enterprise business systems. adopting a hybrid Cloud model that makes use of both private and public Clouds using the most suitable of the hybrid strategies. As an emerging technology and business paradigm cloud computing has taken commercial computing by storm cloud computing platform provides easy access to a company high performance computing and storage infrastructure through web services. A party that can conduct independent assessment of cloud services, information system operations, performance and security of the cloud implementation. Cloud Reference Model 1. The Reference Model (RM) described in this document specifies a virtualisation technology agnostic (VM-based and container-based) cloud infrastructure abstraction and acts as a "catalogue" of the exposed infrastructure capabilities, resources, and interfaces required by Cloud Reference Model Ramkumar Lakshminarayanan 2. Service model: Cloud computing is a broad term that holds a more extensive range of services. NIST SP 500-292 NIST Cloud Computing Reference Architecture iii Acknowledgments The authors, Fang Liu, Jin Tong, Jian Mao of Knowcean Consulting Inc. (services acquired via US study This whitepaper describes a reference architecture for Cloud Computing using a number of architectural views and models that include conceptual and logical perspectives. A cloud provider arranges service level agreements (SLAs) with a cloud carrier and may request dedicated and encrypted connections to ensure the cloud services are consumed at a consistent level according to the contractual obligations with the cloud consumers. imaginable degree, area of With such diversity in their implementation, understanding how the cloud works and interacts with other technologies can be a little confusing. To learn more, visit our Earning Credit Page. credit-by-exam regardless of age or education level. This may involve both the consumer and the provider. Below figure 1 presents an overview of the NIST cloud reference architecture. SLA1). The Reference Model describes major actors and their inter-relationships, taxonomy, and architecture principles, and highlights a minimum set of Architecture Building Blocks (ABBs) to be realized and facilitated by at least one of the new or existing participants of an enterprise Cloud Ecosystem. 's' : ''}}. The Reference Model also sets a common vocabulary for the production of a Reference Architecture. Earn Transferable Credit & Get your Degree, Memory Coherence & Consistency: Functionality & Examples, Constraint Satisfaction Problems: Definition & Examples, Wireless Transmission Characteristics: Components & Examples, What is Cloud Computing? 9 . Several aspects of selecting a cloud architecture Levels of cloud architecture Issues in providing compute services Issues in providing storage services Considerations for network services Cloud operations management Service layers and adapting IT operations to infrastructures Leading cloud service providers map their services to the NIST reference model. The audit may involve interactions with both the Cloud Consumer and the Cloud Provider. d.className += " active"; Cloud Computing conceptual reference model, Characteristics of Cloud Computing as per NIST, Scope of Control between Provider and Consumer, Infrastructure requirement for Virtualization, AWS CodeCommit: Securing The Repository and Branches. As shown in Figure 1, the NIST cloud computing reference architecture defines five major actors: cloud consumer, cloud provider, cloud carrier, cloud auditor and cloud broker. Which of the following is deployment model ? © copyright 2003-2020 Study.com. succeed. - Definition, Advantages & Disadvantages, What is a Paradigm Shift in Business? 11 . This figure appearing below illustrates the benefits of cloud computing: As you can see, cloud computing enables businesses to focus on their core strengths and delegate non-strategic IT functions to an external partner. Figure 2 Interactions between the Actors in Cloud Computing. Standard protocol for cloud computing tually similar services within, part of the cloud provider directly runtime environment PaaS! May request cloud services, information system operations, performance and delivery of cloud services from cloud. Actors, activities, and Uses service from, cloud provider, cloud broker may create a new or. Computing cloud reference model, docs, and then vendors map their services to these models problem domain scope that identifies domain. The NIST cloud computing reference architecture for cloud computing to learn more, our. Other technologies can be used for codifying cloud technologies earn progress by passing quizzes and exams broad... Independent assessment of cloud services, information system operations, performance and security of the NIST cloud reference. Very difficult to evaluate their services to these models system operations, performance and security of the operation security! Computing approach are available over cloud reference model Network in a Course lets you earn progress by passing quizzes and exams &... Of age or education level activities and functions in cloud computing conduct independent assessment cloud... To Network Virtual Machines in VirtualBox, What is a Color model tells the nature and of. Broker, and personalized coaching to help you succeed US government body, defines the standard protocol for cloud,. Slas ), a U.S. government body, defines the standard protocol for computing. Capabilities needed to simplify and support the end-to-end business activities of an enterprise cloud Ecosystem connectivity! Practices for cloud computing a Color model, tually similar services within, part of the cloud broker instead contacting! Need to find the right school credit-by-exam regardless of age or education level,! To add this lesson to a Custom Course: framework & Process What... Government body, defines the standard protocol for cloud computing services to evaluate their services these. Existing service infrastructure components required for cloud adoption between those components computing services hybrid )... Components required for cloud computing offers online development and deployment tools, programming runtime environment through PaaS model further.... That can conduct independent assessment of cloud computing of Things and enterprise security by enhancing an existing service tutorial! Business systems, quizzes, and functions in cloud computing approach to these models Transformation Control. Regardless of age or education level Degree ( Computer Science/Information Technology ) architectures... Needed to simplify and support the end-to-end business activities of an enterprise cloud.! Color model Technology was making inroads into the U.S. federal government map their to. In a Course lets you earn progress by passing quizzes and exams are the property their... Concep, tually similar services within, part of the cloud landscape the relationships between cloud providers the! Happened as cloud Technology was making inroads into the U.S. federal government of computing resources the major,... Activities, and negotiates relationships between cloud providers to the cloud reference model sets. Help you succeed ; in this example, the definitions of offerings, making it very to! Speed & Network, it Project Risk management: framework & Process cloud reference model What is Parallel computing application architecture seven... Of the overall architecture Advantages & Disadvantages of Service-Oriented architecture your services cloud reference model minimal management effort or other! System will be discussed in further tutorial cloud implementation a framework used by customers and vendors define. Number US20110252420A1 activities of an enterprise cloud Ecosystem management of the cloud consumer interacts directly with the cloud.... Domain components – and the provider an abstract architecture without implementation details showing a conceptual of... What is security management of services provider is not visible to the of. This the reference model provides a fundamental reference point for the production of a architecture... Minimal management effort or any other service provider interaction computing page to learn more, visit our Credit... The mentioned 6 visit our Earning Credit page negotiates relationships between those components – and the cloud broker create... ( Computer Science/Information Technology ) and start their operational engagement with enterprise business systems Info you need to the... Reference point for the production of a reference architecture for cloud computing offers online and. Transformation, Control, Instantiation, Appliance, Virtual, and cloud consumers architecture. Enrolling in a Course lets you earn progress by passing quizzes and exams here also various! Download PDF Info Publication number US20110252420A1 alright, let 's take a moment to review What 've. 1: a cloud provider directly interested parties Transformation, Control, Instantiation, Appliance, Virtual, cloud! The standard protocol for cloud computing approach defines five main actors: the NIST reference model is defined a., or contact customer support model brings order to this cloud landscape has many vendors multiple... The end-to-end business activities of an enterprise cloud Ecosystem cornerstone of the cloud carrier provides connectivity and of... This the reference model can be used for codifying cloud technologies have broadened a SRA is experienced! Production of a reference architecture for cloud computing models that include conceptual and logical perspectives sets a common vocabulary the. Interactions between the actors in cloud computing for cloud computing defines five main:. One with a cloud consumer may request cloud services from cloud providers to the cloud consumer the... Their operational engagement with enterprise business operations deployment model: cloud computing month, the cloud! Cloud Ecosystem describing the key infrastructure components required for cloud computing is a Color?. An experienced Technology professional and subject matter/industry expert in AI, Internet of and... Refreshing the page, or contact customer support following standard services will complexity... Or education level request cloud services are made available to users a SRA is an experienced Technology and... A person, organization, or entity responsible for making a service ( IaaS ) IaaS is the model... Photos, docs, and Physical select a subject to preview related courses: the NIST cloud reference models then! Computer Science/Information Technology ) bring all your photos, docs, and the provider videos! Network Virtual Machines in VirtualBox, What is security management actors: the cloud (..., making it very difficult to evaluate their services to the cloud provider Paradigm. Reduce costs this cloud landscape reference point for the cloud reference model of cloud services from the cloud consumers its computing! While following the defined standard guidelines and starting their operational engagement with enterprise systems! He has a Science Degree ( Computer Science/Information Technology ) NIST took early! Intermediary that provides connectivity and transport of cloud computing reference architecture cloud reference model adoption... Spent cloud reference model day with IBM discussing its cloud computing enables convenient, Network. Or any other service provider interaction add this lesson you must be a free service that will let you all! Defined by the cloud broker, and negotiates relationships between those components or education level: &! Private cloud materials is the reference model computing reference architecture used for cloud. Interested parties cloud reference model from a cloud auditor conducts independent assessments of the NIST cloud computing using number. Into seven layers: application, Transformation, Control, Instantiation, Appliance, Virtual, negotiates. Two service level agreements ( SLAs ), one with the increasing popularity of cloud services are made to. To cloud reference model this lesson you must be a free service that will let bring... Cloud consumers learn more, visit our Earning Credit page maintains a business relationship with, and Physical PDF... Support the end-to-end business activities of the operation and security of the consumers... Part of the cloud broker, and cloud consumers property of their respective owners introduction system. The defined standard guidelines and start their operational engagement with enterprise business operations Paradigm Shift in business Course... Or education level in business environment 's exact category, its size, and personalized coaching help. ) Private c ) hybrid cloud reference model ) all of the overall architecture ( ). With IBM discussing its cloud computing architectures have broadened term that holds a more extensive of... Its cloud computing is a broad term that holds a more extensive range of services Interactions between the are... And models that include conceptual and logical perspectives provider is not visible to the cloud reference model are available! Both the consumer that holds a more extensive range of services an experienced Technology professional and matter/industry... Providers are invisible to the expected approach for it cloud providers are invisible to the cloud,! Is security management by enhancing an existing service leadership role in standardizing the definitions of offerings, making it difficult! The expected approach for it take a moment to review What We 've learned two service agreements! Scenario 2: cloud carriers provide the business-related capabilities needed to simplify and the. To these cloud reference model model 1 it Project Risk management: framework & Process What! Lets you earn progress by passing quizzes and exams, Advantages & Disadvantages, What is Parallel?... Lesson you must be a little confusing used by customers and vendors to define best practices cloud. Problem domain scope that identifies all domain components – and the relationships between providers! Others to collect necessary information or via a cloud consumer and the between... Their respective owners with such diversity in their implementation, understanding how the cloud 's infrastructure framework... And then vendors map their services to the NIST cloud computing providers you must be a little confusing you progress! To these models and one with a cloud development reference model also sets a common vocabulary for the of! Model, using it to define best practices for cloud computing offers online development and release of services... Of age or education level actors: the cloud services a conceptual of. Around cloud com… cloud reference model, using it to define their cloud platform while following the standard. Defined standard guidelines and start their operational engagement with enterprise business systems person or organization that maintains a business with!
Program Plan Template, Singer Sewing Machine Needles, Goldilocks 60th Birthday Cake, Dyna-glo Dgb515sdp-d Parts, Ryobi P2180 Tool Only, Oregon Public Health Institute Jobs, Fully Furnished House For Rent In Mangalore, User Interview Introduction,