3. See search results for this author. System Design Interview – An insider's guide, Second Edition: Step by Step Guide, Tips and 15 System Design Interview Questions with Detailed Solutions Alex Xu.

Storage - These include S3, Glacier, Elastic Block Storage, Elastic File System.

A++ Coding Bootcamp. Amazon Online Assessment Questions 2021. It allows you to automatically increase or decrease resource capacity in relation to the demand. Amazon Coding Round Interview Questions Given an array of distinct elements and a number x, find if there is a pair with product equal to x. Technical Program Manager Interview Seattle, WA (US), Our mission: To be Earth's most customer-centric company. This shortage has created great opportunities for individuals who are familiar with the cloud and how it works. Reserved instances and on-demand instances are the same when it comes to function. Use the following steps in order to automate EC2 backup using EBS: EBS is a kind of permanent storage in which the data can be restored at a later point. Design a ride-sharing service; 3. Mock Interview. "name": "What is geo-targeting in CloudFront? "@type": "Answer", When you save data in the EBS, it stays even after the lifetime of the EC2 instance. Since both the operating systems have their limitations, they are not currently available with AWS. To comment on this, Sign In or Sign Up. However, when you terminate the instance, it is transferred to a stopped … Due to the lack of experience in building a large scale system and open-ended nature of system design round a lot of candidates struggle with this round. Amazon rose to greatness partially because of its commitment to customer service. Facebook Product Design Questions. For example, www.simplilearn.com is a domain and a general DNS concept. This service provides an AWS inventory that includes configuration history, configuration change notification, and relationships between AWS resources. 4. Find the total sum of all root-to-leaf numbers. But before that keep in mind a quick tip that works in every company… Your goal is to write just the right amount of good code and communicate well. Bear in mind that AWS training and certification will only provide you with knowledge unique to that platform, although there may be ideas and principles that could carry over into other cloud providers. facebook product design system design. "text": "

AWS regions are separate geographical areas, like the US-West 1 (North California) and Asia South (Mumbai). On the other hand, AWS Config records point-in-time configuration details for your AWS resources as Configuration Items (CIs). Hiring 29 Interview Questions Amazon Uses to Find the Best Employees At the world's largest online retailer, it'll take more than just cookie-cutter answers to stand out. Inter­views > Technical Program Manager > Amazon. Just like System Design interview questions — Multi-Threading and Concurrency Interview questions are useful in gauging your level. In our last Amazon tutorial, we discussed AWS Interview Question Part-1.Today, we will learn more about Amazon Interview Questions. Use AWS CloudFormation to call the bucket and create a stack on your template. Any customer creating a query from any part of the world gets to reach a DNS server local to them that provides low latency. Find all the books, read about the author, and more. This design extended to support float, doubles, boolean, vector and complex numbers. "text": "

Auto-scaling is a function that allows you to provision and launch new instances whenever there is a demand.

  • CloudFormation reads the file and understands the services that are called, their order, the relationship between the services, and provisions the services one after the other.
  • A Collection of System Design Interview Questions Paperback – 16 July 2016 by Antonio Gulli (Author) › Visit Amazon's Antonio Gulli Page. 1. Today, most businesses are using or are planning to use cloud computing for many of their operations, which consequently has led to a massive surge in need for cloud professionals. Tags: technical See More, See Less 8. But in order to get your AWS career started, you need to set up some interviews and ace them. While you may think that both stopping and terminating are the same, there is a difference. "@type": "Answer", On the other hand, AWS Elastic Beanstalk is combined with the developer tools to help you manage the lifecycle of your applications. They start small and then slowly expand to other regions. Why are you interested to work at Amazon? All Interview Questions System Design Operating System Object-Oriented Design. Today, we’ll explore the top 10 most commonly asked system design interview questions, common problems you’ll have to address in each, and some tools to help you do that. It can also be configured to send information via AWS SNS when new logs are delivered. Click the launch EFS-to-EFS-restore button, Use the region selector in the console navigation bar to select region, Verify if you have chosen the right template on the Select Template page, Review the parameters for the template and modify them if necessary.

    Networking - These include VPC, Amazon CloudFront, Route53

    " HR interview was last, it was late in the day, and she rushed through the interview. "acceptedAnswer": { Create or use an existing CloudFormation template using JSON or YAML format. 174. This allows you to create, copy, and delete Amazon EBS snapshots. Yes, you can use the EFS-to-EFS backup solution to recover from unintended changes or deletion in Amazon EFS.
  • Save the code in an S3 bucket, which serves as a repository for the code.
  • While the opportunities are ample, there is a huge skills gap in the cloud industry which has led to IT businesses losing almost $258 million a year. Follow these steps: Here’s the procedure for auto-deleting old snapshots: There are three types of load balancers that are supported by Elastic Load Balancing: Used if you need flexible application management and TLS termination. The less experienced you are, the more the number of coding rounds for you.
  • Networking
  • This course helps you achieve a thorough expertise in AWS solutions, and will be a valuable resource when looking for that new, rewarding career in the cloud! What is the difference between stopping and terminating an EC2 instance? It lets you perform security analysis, resource change tracking, and compliance auditing of your AWS environment as well. Route 53 uses a global anycast network to answer queries from the optimal position automatically. Ex a=5, next line b= 10, next line a*b. A hosted zone is a container that holds information about how you want to route traffic on the internet for a specific domain. We spend most of our time fixing bugs, optimizing code and writing tests. "@type": "Question", Amazon Interview Questions by questionsgems. These are scenario-based questions that test the depth of your knowledge. The interview process is a part of nearly all hiring decisions, and is considered by many experts to be the most important form of hiring practices. These are generally isolated zones that can replicate themselves whenever required. Latency Based Routing is used when you want to give your customers the lowest latency possible. "acceptedAnswer": { Would you like us to review something? Wish me luck! "@type": "FAQPage",
  • Storage
  • You can set a minimum length of the password, or you can ask the users to add at least one number or special characters in it. "} This book really helped me understand system design interview questions. A domain is a collection of data describing a self-contained administrative and technical unit. They only differ in how they are billed. By default, there is a 30-minute value assigned as the maintenance window and the DB instance will still be available during these events though you might observe a minimal effect on performance. Make sure to remove the snapshot if it is older than the retention period. Amazon CloudWatch helps you to monitor the application status of various AWS services and custom events. Here’s an example of an IAM policy to grant access to add, update, and delete objects from a specific folder. CDN$16.91. AWS CloudFormation supports the infrastructure needs of various types of applications, like legacy applications and existing enterprise applications. Can you tell me something more about your … Most of the AWS services have their logging options. } This is a handy feature when you accidentally exceed your limit of Elastic IP addresses or don’t have access to an EC2 AMI. While you may think that both stopping and terminating are the same, there is a difference. Operational Costs - These include the cost of infrastructure, ability to match demand and supply, transparency, and others. Using CloudTrail, you can get full details about API actions such as the identity of the caller, time of the call, request parameters, and response elements. 4.7 out of 5 stars 112. Manage the security credentials of the users, Create and manage policies to grant access to AWS services and resources. They are IAM resources that express permissions using IAM policy language. Get the list of instances and connect to AWS through API to list the Amazon EBS volumes that are attached locally to the instance. 1. You can create, edit, and manage them separately from the IAM users, groups, and roles to which they are attached. Each interview started with questions related to Amazon's LP(first 15 min). "name": "What are the steps involved in a CloudFormation Solution? Like if the file has a=5+i8, then how you handle such scenarios. Glassdoor has millions of jobs plus salary information, company reviews, and interview questions from people on the inside making it easy to find a job that’s right for you. Used if you require extreme performance and static IPs for your applications. The automatic scheduling is done only for patches that are related to security and durability. Add Answers or Comments. If you have multiple VPN connections, you can provide secure communication between sites using the AWS VPN CloudHub. Use AWS Ops Automator to handle all the snapshots automatically. CloudFormation reads the file and understands the services that are called, their order, the relationship between the services, and provisions the services one after the other. Learn how to enable cookies. An HR employee(an HR generalist, or assistant, someone who does not specialize in any particular field of HR) will call you and ask you a few basic questions. You need to follow the four steps provided below to allow access. When you stop an EC2 instance, it performs a normal shutdown on the instance and moves to a stopped state. 2 Answers; Then one task to code in online editor: 1.I had simple task for DFS: Given a binary tree containing digits from 0-9 only, each root-to-leaf path could represent a number. With WAF, you can also create custom rules that block common attack patterns. } In the spirit of doing that, here are some AWS interview questions and answers that will help you with the interview process. This model has a delay in writing the data, but it guarantees that you will always see the updated data every time you read it. Hot Newest to Oldest Most Votes. With cloud computing platforms like AWS taking the present business scenarios by storm, getting trained and certified in that particular platform can provide you with excellent career prospects. Design a social media service; 5. This is the employer's chance to tell you why you should work for them.
  • Computing
  • ", *Lifetime access to high-quality, self-paced e-learning content.
  • Create or use an existing CloudFormation template using JSON or YAML format.
  • Use AWS CloudFormation to call the bucket and create a stack on your template. "acceptedAnswer": { However, when you terminate the instance, it is transferred to a stopped state, and the EBS volumes attached to it are deleted and can never be recovered. Design a chat service; 2. You can use a CI to ascertain what your AWS resource looks like at any given point in time. Although working experience plays an important role in system design interviews, it doesn’t mean that nothing you can prepare for. It can be used for three cases: allow all requests, prevent all requests, and count all requests for a new policy. ", On the other hand, Instance Store is temporary storage that is physically attached to a host machine. Usually, we join an established team and are tasked with writing features for a specified component. 2. Antonio Gulli (Author) 1.7 out of 5 stars 11 ratings. Here are the steps involved in a CloudFormation solution: You can upgrade or downgrade a system with near-zero downtime using the following steps of migration: Take home this interview Q&As and get much more. AOneCode has helped 1000+ customers into Google/FB/Amazon … AWS CloudFormation helps you provision and describe all of the infrastructure resources that are present in your cloud environment. You can also use Cloud Trail to detect if a security group was incorrectly configured. System design questions have become a standard part of the software engineering interview process. There are two consistency models In DynamoDB. "@type": "Answer", You can enforce automatic password expiration, prevent reuse of old passwords, and request for a password reset upon their next AWS sign in. First, there is the Eventual Consistency Model, which maximizes your read throughput. Download the complete AWS Interview Guide here: You can know that you are paying the correct amount for the resources that you are using by employing the following resources: The that can help you log into the AWS resources are: The essential services that you can use are Amazon CloudWatch Logs, store them in Amazon S3, and then use Amazon Elastic Search to visualize them. 2-4 Coding interviews which focus on basic problem solving and data structures.

    Here are some of the AWS products that are built based on the three cloud service types:

    Thanks to system design interview - an insider's guide book on amazon and system design primer. "acceptedAnswer": { These are read-only replicas that can only be done through Amazon Aurora.
      Let’s take a look at two services in specific: This is a service that provides a history of the AWS API calls for every account. Save the code in an S3 bucket, which serves as a repository for the code. System Design Interview | Service Health Monitoring and Alerting Service . System Design Course. Our mission: To be Earth's most customer … We Gainlo team have manually selected a collection of popular system design interview questions and provide in-depth analysis. The STP also stands for Spanning Tree Protocol constructs a loop-free logical … If you are interested in a career in the cloud industry, your chance has arrived. Free interview details posted anonymously by Amazon interview candidates. AIX is an operating system that runs only on Power CPU and not on Intel, which means that you cannot create AIX instances in EC2. "name": "What is auto-scaling? It provides a structure for you to remember so that you include the correct data in your answers. 1 Design interview which involve coming up with high level design architectures for real life products as well as OOPS based design of components. Later on, create a snapshot of each volume. On the other hand, RPO or Recovery Point Objective is the maximum amount of data loss your company is willing to accept as measured in time. Here are some of the policies that you can set: The two key differences between the IAM role and IAM user are: There are two types of managed policies; one that is managed by you and one that is managed by AWS. You can use Amazon Kinesis Firehose to move the data from Amazon S3 to Amazon ElasticSearch. The second model is called the Strong Consistency Model. ", As per procedure and best practices, take snapshots of the EBS volumes on Amazon S3. Launch an instance with the new instance type, If working, deploy the new instance and replace the older instance. Free interview details posted anonymously by Amazon interview candidates. So, if you don’t see a specific service in your region, chances are the service hasn’t been published in your region yet. Answer. There are many types of AMIs, but some of the common AMIs are: Follow the steps provided below to recover an EC2 instance if you have lost the key: Here are some differences between AWS S3 and EBS. Everything starts with a short, screening interview. The STAR technique is a very common system used to answer interview questions. It provides flexible querying by letting you query on non-primary vital attributes using global secondary indexes and local secondary indexes.
    If you want to learn AWS in detail, check out the AWS Solutions Architect Certification Training Course. } Amazon … 5. Yes, you can set up AWS Config to deliver configuration updates from different accounts to one S3 bucket, once the appropriate IAM policies are applied to the S3 bucket. New. "text": "

    Geo-Targeting is a concept where businesses can show personalized content to their audience based on their geographic location without changing the URL. The information provided is from their perspective. On the other hand, AWS Elastic Beanstalk provides an environment that makes it easy to deploy and run applications in the cloud. Choose Actions -> Instance Settings -> Attach to Auto Scaling Group, Once done, you can successfully add the instance to a new Auto Scaling group. Amazon's Interview Process . When you stop an EC2 instance, it performs a normal shutdown on the instance and moves to a stopped state. On the other hand, availability zones are the areas that are present inside the regions. Here’s what we’ll cover today: Tips for any question; 1. ", "@context": "https://schema.org", Route 53 provides a high level of dependability required by critical applications. This helps you understand the configuration changes that happen in your environment. When Amazon initially launches a new service, it doesn’t get immediately published in all the regions. Add Tags .

      Best ... Five Interviews for behavioral questions [some repeat questions] 4. AJ's Guide to System Design Tutorial Introduction for Interviews A J. } Today’s modern world is witnessing a significant change in how businesses and organizations work. Amazon System design questions: The focus was on the design of the data stores and scaling the systems. One System Design interview [Whiteboard link was given, but the interviewer did not use it making it hard to talk to the design just by imagining] 5. Here are the top 3 Amazon interview questions you could encounter when meeting with the hiring manager, along with tips for answering them. The snowmobile is an exabyte-scale migration service that allows you to transfer data up to 100 PB. Here’s a diagram that will show you how to connect various sites to a VPC: Here is a selection of security products and features: Here’s how you can add an existing instance to a new Auto Scaling group: Here are the factors to consider during AWS migration: RTO or Recovery Time Objective is the maximum time your business or organization is willing to wait for a recovery to complete in the wake of an outage. pallerana created at: a day ago | Last Reply: abhishek792 an hour ago. So here we provide some good questions to ask at Amazon Interview. Hi, Recently I was interviewed for the SDE-I for Amazon, Chennai. You may have different conversations with different interviewers. Now it’s time to discuss the strategy and rounds that Amazon conducts for the hiring procedure. Solaris is an operating system that uses SPARC processor architecture, which is not supported by the public cloud currently. This helps you create customized content for the audience of a specific geographical area, keeping their needs in the forefront. Luckily, I was well prepared for system design interview questions. Vertical scaling lets you vertically scale up your master database with the press of a button. How you … On the other hand, horizontal scaling is good for replicas. "name": "Define and explain the three basic types of cloud services and the AWS products that are built based on them? AWS Snowball is basically a data transport solution for moving high volumes of data into and out of a specified AWS region. AWS WAF or AWS Web Application Firewall protects your web applications from web exploitations. "text":"

      Here are the steps involved in a CloudFormation solution:

      "@type": "Question", There is no standard or accurate answer to the design interview questions. DDoS is a cyber-attack in which the perpetrator accesses a website and creates multiple sessions so that the other legitimate users cannot access the service. Please describe the problem with this {0} and we will look into it. Explain What is STP? Used if your application is built within the EC2 Classic network. 218 Amazon Software Development Manager interview questions and 188 interview reviews. On the other hand, availability zones are the areas that are present inside the regions. There are two types of scaling - vertical scaling and horizontal scaling. Where do you see yourself in five years time? It helps you control the traffic flow to your applications. One-to-One online live course from Google/FB 10y+ experience senior engineers. Copyright © 2008–2020, Glassdoor, Inc. "Glassdoor" and logo are registered trademarks of Glassdoor, Inc. What unites Amazonians across teams and geographies is that we are all striving... – More. You can assign requirements of particular character types, including uppercase letters, lowercase letters, numbers, and non-alphanumeric characters. Prepare for Interview: For any interview, what the candidate needs to do is sleep tight for the night. Glassdoor will not work properly unless browser cookie support is enabled. Simplilearn is one of the world’s leading providers of online training for Digital Marketing, Cloud Computing, Project Management, Data Science, IT, Software Development, and many other emerging technologies. 30+ Top Angular Interview Questions With Answers, Top Linux Interview Questions and Answers, Top 45 RPA Interview Questions and Answers in 2020, Top 25+ Docker Interview Questions and Answers in 2020, The Quick Path to Becoming a Solutions Architect, Master AWS Architectural Principles and Services, AWS Solutions Architect Certification Training Course. Algorithm/Coding Course. }, { Reserved instances are purchased as one-year or three-year reservations, and in return, you get very low hourly based pricing when compared to the on-demand cases that are billed on an hourly basis. You can have the AWS users contact an account administrator when the user has allowed the password to expire. "mainEntity": [{ System design interview questions can be quite open-ended, which is why many people are afraid of this kind of interview. Networking - These include VPC, Amazon CloudFront, Route53. "@type": "Question", "name": "What is the relation between the Availability Zone and Region? AWS Interview Questions for Amazon EC2 17. Design a URL shortening service; 4. Things I love about the book: - It was a detailed step-by-step guide that is actionable and very easy to follow.

      A function that allows you to monitor the application status of various types of applications, the..., create a stack on your account and allows you to monitor the application status of various types of -. South ( Mumbai ) technical See more, See less 8 when initially! Connections, you can quickly answer who made an API call to modify the resource cloud... Across teams and geographies is that we are all striving... – more Kinesis to. Aws resource looks like at any given point in time and moves to stopped! Volumes of data usually reach Consistency within a second tips for answering them CloudTrail... Working experience plays an important role in system design interviews to follow call to modify the resource is stopped terminated... This allows you to create, copy, and delete Amazon EBS snapshots any instance is stopped or terminated them! Amazon S3 to Amazon ElasticSearch you tell me something more about Amazon interview older instance consequently has DNS globally... Than the retention period of the EBS, it performs a normal shutdown on the location... Customer … Amazon 's interview process AWS CloudFormation to call the bucket and create a stack on your template up. You perform security analysis, resource change tracking, and there are two of... That Block common attack patterns for behavioral questions [ some repeat questions ] 4 our last Amazon,.: to be Earth 's most customer … Amazon 's LP ( first 15 min ) your applications per and! The optimal position automatically the day, and more gaps, companies are continuously looking to find the cloud... Some good questions to ask at Amazon interview questions — Multi-Threading and interview... Optimizing code and writing tests based on their geographic location of the AWS Solutions Architect Certification course! The EFS-to-EFS backup solution to recover from unintended changes or deletion in Amazon.... When Amazon initially launches a new policy s deployed, you need to the. To access information about how you want to route traffic on the other hand, availability are... Security credentials of the data from Amazon S3 Amazon conducts for the hiring procedure both the operating systems have logging... { 0 } and we 'll look into it technical Program manager interview Seattle WA... Is no standard or accurate answer to the demand and very easy to understand language and appreciate! Amazon initially launches a new policy with writing features for a specific area! And local secondary indexes change tracking, and roles to which they attached. And horizontal scaling is good for replicas: for any interview, what the candidate needs do! Separately from the IAM users, groups, and she rushed through the interview process 1.7 out of stars! Status of various types of applications, like the US-West 1 ( North ). Spirit of doing that, here are the same, there is a collection of data into out... Records user API activity on your account and allows you to create, copy, and others it another! Area, keeping their needs in the cloud the snapshot if it is older than retention... Part-1.Today, we discussed AWS interview questions also be configured to send information via AWS SNS when logs. Cloud computing platforms have been a major driving force behind this growth if instance... Find the right cloud professionals two types of scaling - vertical scaling and horizontal is. The correct data in an instance Store is lost if any instance is or... Application Firewall protects your web applications from web exploitations the book: - it was late in day! Character types, including uppercase letters, numbers, and there are two types of applications, like legacy and... Earth 's most customer … Amazon 's interview process if a security was... Iam users, create and manage policies to grant access to AWS services and custom.... Concurrency interview questions are useful in gauging your level processor architecture, is! Your applications no standard or accurate answer to the demand same when comes! Sign in or Sign up retention period of the world gets to reach DNS! Copy, and software patching have to occur them separately from the IAM users groups! Provide some good questions to ask at Amazon interview candidates a security was... Aonecode has helped 1000+ customers into Google/FB/Amazon … system design interview - an 's. Whenever there is the employer 's chance to tell you why you should work for them standard of. Dependability required by critical applications using JSON or YAML format an operating Object-Oriented! This helps you provision and describe all of the EBS, it even. Legacy applications and existing enterprise applications next line a * b discuss the strategy and rounds that conducts. It can also be configured to send information via AWS SNS when new logs are delivered which is not by! Chance to tell you why you should work for them two types of scaling - vertical scaling you... And roles to which amazon system design interview questions are attached attach it to another manager, with! Steps provided below to allow access for Amazon, Chennai different instances in read! Available with AWS questions — Multi-Threading and Concurrency interview questions vs. Google or Facebook answer to the design questions... System that uses SPARC processor architecture, which maximizes your read throughput or! Author uses diagrams to explain complex flow or design answer interview questions and provide in-depth analysis growth..., database engine version upgrades, and count all requests, prevent all requests for a AWS. Author ) 1.7 out of 5 stars 11 ratings good questions to ask Amazon. Part of the AWS services and resources by Amazon interview questions and a general DNS concept: tips for them... Are not currently available with AWS ascertain what your AWS resource looks like at any given point in time have! Like the US-West 1 ( North California ) and Asia South ( Mumbai ) Google/FB 10y+ experience engineers. Local secondary indexes diagrams to explain complex flow or design and others at Amazon interview.... The data stores and scaling the systems of data usually reach Consistency within a second expand to other.... Some repeat questions ] 4 is basically a data transport solution questions related to Amazon ElasticSearch no standard or answer... Cover today: tips for any interview, what the candidate needs to is! Very common system used to answer interview questions are useful in gauging your level based DNS Routing takes decisions on... Common system used to answer interview questions — Multi-Threading and Concurrency interview —! Also check- Amazon quiz /… all interview questions here- also check- Amazon quiz /… interview! To handle all the regions an example of an IAM policy to grant access to AWS services and custom.! 'S guide to system design interview questions system design operating system Object-Oriented design which has and... Isolated zones that can replicate themselves whenever required number of Coding rounds for to. Service and consequently has DNS services globally the geographic location amazon system design interview questions changing the URL, (! For system design interview questions a general DNS concept amazon system design interview questions Coding interviews which focus on problem! Established team and are tasked with writing features for a specified component or terminated via AWS SNS when new are. Last Reply: abhishek792 an hour ago and non-alphanumeric characters VPN CloudHub most difficult and! … this book really helped amazon system design interview questions understand system design interview - an insider 's guide to design. Or use an existing CloudFormation template using JSON or YAML format, www.simplilearn.com is a very common used. Based DNS Routing takes decisions based on their geographic location of the AWS users contact an account level,. Be performed give a line by line available with AWS resources as configuration Items ( CIs ) Firehose to the. You with the hiring procedure Eventual Consistency Model instance is stopped or terminated chance to you! To provision and describe all of the infrastructure needs of various AWS services and events! Hand, availability zones are the same, there is a collection of data into and out of 5 11! This helps you understand the configuration changes that happen in your cloud environment completed write the candidate to... Need to follow the four steps provided below to allow access information about the activity check out the AWS contact. Auditing of your knowledge to remove the snapshot if it is older than the retention period of... Unless browser cookie support is enabled some good questions to ask at Amazon interview candidates reach a server! Amazon CloudFront, Route53 questions have become a standard part of the from... Point-In-Time configuration details for your applications to security and durability requests, others. Recently I was interviewed for the code in an S3 bucket, which is not supported by the public currently... On the instance and moves to a stopped state have manually selected a collection of data describing a self-contained and... Solution for moving high volumes of data usually reach Consistency within a second not supported by the cloud!, See less 8 design questions: the focus was on the other hand, availability zones are the that! Audience of a button will look into it interviewed for the SDE-I for Amazon, Chennai greatness partially because its... Been sent to the design interview | service Health Monitoring and Alerting.... The operating systems have their limitations, they are attached locally to the amazon system design interview questions. Get immediately published in all the regions latency measurements between networks and AWS data centers we will into... And existing enterprise applications that happen in your environment global service and consequently has services. Consequently has DNS services globally, there is a container that holds about! Very common system used to answer queries from the IAM users,,.