UNIT1 Flashcards
What is computing?
Computing is using technology to design software and hardware, process and manage information, solve problems, and perform calculations and data analysis.
What is a distributed system?
A distributed system consists of multiple computers working together as one system without sharing memory, communicating via messages.
Give an example of a distributed system.
Examples include telecommunication networks, MMOs (Massively Multiplayer Online Games), and the World Wide Web.
What is a single-system image in a distributed system?
It makes the system appear as a single unified entity to users, hiding internal complexities.
What is the main difference between centralized and distributed systems?
Centralized systems have one main control point, while distributed systems have multiple autonomous components working together.
Which system is more fault-tolerant: centralized or distributed? Why?
Distributed systems, because if one node fails, others can continue running.
List two advantages of distributed systems.
Increased speed for parallel processing and improved reliability.
What is a major disadvantage of distributed systems?
Complexity in software development and network-related issues.
What is cluster computing?
A group of computers linked to work as one powerful system, often used for performance improvement and cost-effectiveness.
What are the main types of cluster computing?
High Availability (HA), Load Balancing (LB), and HA+LB combination.
What is the role of middleware in cluster computing?
Middleware like MPI helps different clusters communicate and execute programs efficiently.
How is grid computing different from cluster computing?
Grid computing involves geographically dispersed computers contributing unused resources, while clusters have tightly connected nodes.
Name a real-world example of grid computing.
SETI@Home, which uses home computers to analyze space signals.
What are the key layers of grid computing architecture?
Fabric, Connectivity, Resource, Collective, and Application layers.
What are the three main components of mobile computing?
Mobile communication (network infrastructure), mobile hardware (devices), and mobile software (applications & OS).
Why is mobile computing important?
It enables data, voice, and video transmission without a fixed physical link.
What is cloud computing?
A model of computing where services (hardware, software, storage) are provided over the internet.
What are the three cloud service models?
IaaS (Infrastructure as a Service), PaaS (Platform as a Service), and SaaS (Software as a Service).
What is the difference between public and private cloud?
Public cloud is available to the general public, while private cloud is restricted to a specific organization.
Which cloud deployment model combines public and private clouds?
Hybrid cloud.
How does ownership differ in cluster, grid, and cloud computing?
Clusters are owned by a single entity, grids are owned by multiple parties, and clouds are usually controlled by a provider.
Which computing model provides dynamically allocated resources?
Cloud computing.
Why is cloud computing considered scalable?
It allows resources to be allocated or deallocated based on demand.
What type of computing is used by Google Drive or Dropbox?
Cloud computing (SaaS model).
Which computing model is best for scientific simulations requiring high computational power?
Cluster computing.
What is a data center?
A facility that centralizes an organization’s IT operations and equipment, where it stores, manages, and disseminates data.
What are the two types of data center locations?
On-premise and off-premise.
What does ‘On-demand self-service’ mean in cloud computing?
Users can access computer services without requiring human interaction with each service provider.
Name some cloud service providers that provide on-demand self-services.
Amazon Web Services (AWS), Microsoft Azure, Google Cloud, IBM, and Salesforce.com.
What does ‘Broad network access’ mean in cloud computing?
Cloud capabilities are available over the network and accessed through standard mechanisms.
What types of client platforms can access cloud services with broad network access?
Mobile phones, laptops, and PDAs.
What does ‘Resource pooling’ mean in cloud computing?
The provider’s computing resources are pooled to serve multiple consumers using a multiple-tenant model.
What types of resources are included in resource pooling?
Storage, processing, memory, network bandwidth, virtual machines, and email services.
What is ‘Rapid elasticity’ in cloud computing?
Cloud services can be rapidly and elastically provisioned to quickly scale out and rapidly released to quickly scale in.
What does ‘Measured service’ mean in cloud computing?
Cloud computing resource usage can be measured, controlled, and reported, providing transparency for both the provider and consumer.
How are cloud computing services typically charged?
Per hour of resource usage, by the number of transactions, amount of storage, or data transferred over a network.
What are the benefits of elasticity for cloud provider’s customers?
Achieve cost savings, often a core reason for adoption of cloud services.
List some benefits of cloud computing.
Flexibility, Disaster recovery, Automatic software updates, Increased collaboration, Work from anywhere, Cost-saving, etc.
How does cloud computing assist in disaster recovery?
By providing cloud-based backup and recovery solutions that save time and avoid large upfront investments.
What is the advantage of automatic software updates in the cloud?
Suppliers take care of software updates, including security, eliminating the need for manual maintenance.
How does cloud computing enable increased collaboration?
Cloud-based workflow and file sharing apps allow teams to access, edit, and share documents anytime, from anywhere.
How does cloud computing allow for work from anywhere?
With an internet connection and mobile apps, users can access their work from any device.
How does cloud computing impact capital expenditure?
It cuts out the high cost of hardware, offering a subscription-based model that is kind to cash flow.
How does cloud computing improve document control?
All files are stored centrally, so everyone sees one version of the truth, improving collaboration.
How does cloud computing enhance security?
Data is stored in the cloud, accessible regardless of machine issues, and can be remotely wiped from lost devices.
How does cloud computing provide competitiveness to businesses?
It gives access to enterprise-class technology, allowing smaller businesses to act faster than larger competitors.
How does cloud computing contribute to being environmentally friendly?
It uses energy more efficiently, scaling server capacity to fit needs, reducing carbon footprints.
What does NIST stand for?
National Institute of Standards and Technology.
Name some cloud actors (providers).
Amazon EC2, Google App Engine, Google Apps, Microsoft Office Online, Apple iCloud, DigitalOcean.
Name a few cloud consumers who are top AWS users.
Netflix, Twitch, LinkedIn, Facebook, Turner Broadcasting, BBC, Baidu, ESPN, Adobe, Twitter.
What is cloud auditing?
Checking cloud services to make sure they meet certain standards and regulations.
What do deployment models define in cloud computing?
The type of access to the cloud.
What is a private cloud?
A cloud where systems and services are accessible within an organization, offering higher security.
How can a private cloud be managed?
Managed by the organization or a 3rd party and located on or off-premise.
What is a public cloud?
A cloud where systems and services are accessible by the general public but offers lesser security.
What type of infrastructure does a public cloud usually have?
Mega scale infrastructure, globally distributed.
What is a community cloud?
A cloud where systems and services are accessible by a group of organizations (sharing common interests).
How is a community cloud managed?
Managed by the organization or a 3rd party.
What is a hybrid cloud?
A mixture of public and private clouds where critical activities are performed by the private cloud and non-critical activities by the public cloud.
Name companies that heavily rely on hybrid cloud data storage.
Netflix, Hulu, Uber, and Airbnb.
What is a primary advantage of a public cloud regarding cost?
Organizations do not need to buy, install, operate, or maintain servers or other equipment.
What is a primary security disadvantage of a public cloud?
Hardware resources are shared between multiple users, making IT security issues more profound.
What is a key advantage of a private cloud regarding security?
Operations are not available to the general public, ensuring higher security and privacy.
What is a potential disadvantage of a private cloud regarding scalability?
Can be scaled only within the capacity of internal hosted resources.
List a flexibility advantage that the hybrid cloud provides.
Combines secure resources with scalable public resources.
What are some disadvantages of hybrid cloud?
Networking issues, Security compliance, High cost.
What is the main advantage of community cloud regarding cost?
It offers the same advantages as a private cloud at a lower cost.
What is a potential data accessibility disadvantage in a community cloud?
Data might be accessible by others in the community.
What are the three basic service models in cloud computing?
Infrastructure-as-a-Service (IaaS), Platform-as-a-Service (PaaS), Software-as-a-Service (SaaS).
What does IaaS provide?
Access to fundamental resources such as physical machines, virtual machines, and virtual storage.
Name a few well-known examples of IaaS.
DigitalOcean, Linode, Rackspace, Amazon Web Services (AWS), Microsoft Azure, and Google Compute Engine (GCE).
What is one key benefit of IaaS?
Full control of the computing resources through Administrative Access to VMs.
What is the biggest issue of using IaaS?
Vendor lock-in.
What does PaaS provide?
The runtime environment for applications, development and deployment tools, etc.
Name a few well-known examples of PaaS.
Google’s App Engine, Microsoft Azure, AWS Elastic Beanstalk, Heroku.
What is a key benefit of PaaS?
Automated updates.
List a disadvantage that PaaS has.
Compatibility of Existing Infrastructure.
What does SaaS provide?
Access to applications on demand over the Internet.
What are a few examples of SaaS?
Google Apps, Salesforce.com, Social Networks, Office Suits.
What are main issues for SaaS?
Insufficient Data Security.
What is a Recovery as a Service (RaaS)?
RaaS protects applications/data from disasters by enabling a full recovery in the cloud.
How does RaaS capacity get delivered?
In a cloud-computing model, so recovery resources are only paid for when they are used.
What is cloud computing and its benefits?
Cloud computing is a model for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction.
List at least three ways cloud computing helps businesses.
- Reducing IT infrastructure costs
- Enabling scalability
- Enhancing collaboration
- Improving disaster recovery
What are public cloud deployment issues?
- Less secure than other options
- Lacks proper controls. The client has no control of data or infrastructure
What is Virtualization?
Sharing a single physical resource (server, application) among multiple users or organizations.
How does Virtualization work?
It gives a logical name to physical storage and provides a pointer to that physical resource when demanded.
What is a Host Machine in Virtualization?
The machine on which the virtual machine is built.
What is a Guest Machine in Virtualization?
The virtual machine itself.
What is a Hypervisor?
A program/firmware that manages virtual machines (VMs) and allocates resources. Also known as Virtual Machine Manager (VMM).
What are the two main types of Hypervisors?
Type 1 (Bare-Metal) and Type 2 (Hosted).
Where does a Type 1 Hypervisor run?
Directly on the hardware.
Does Type 1 Hypervisor need a separate OS?
No.
Where does a Type 2 Hypervisor run?
On top of an existing operating system (like Windows or macOS).
Type 1 Hypervisor design
The hypervisor sits directly on the hardware, and the guest operating systems run on top of the hypervisor.
Type 2 Hypervisor design
The hardware has a host operating system, and the hypervisor is installed on that OS. Then, the guest operating systems run on the hypervisor.
What are the advantages of Type 1 Hypervisors?
Better performance, greater flexibility.
Are servers that run Type 1 hypervisors single-purpose or multi-purpose?
Single-purpose.
What is the purpose of Type 1 hypervisors?
Offer services to users.
What type of virtualization do Type 1 hypervisors support?
Hardware virtualization.
What are the disadvantages of Type 2 Hypervisors?
Less efficient, less flexible.
Are Type 2 hypervisors rarely used in production?
Yes.
What type of virtualization do Type 2 hypervisors perform?
Software virtualization.
Name the different types of virtualization
Hardware, Software, Memory, Storage, Data, Network, and Desktop.
What is Hardware Virtualization?
Creating virtual versions of physical hardware components (e.g., virtual servers from one physical server).
What is the difference between a simulator and an emulator?
A simulator is designed to create an environment that contains all of the software variables and configurations that will exist in an app’s actual production environment, while an emulator attempts to mimic all of the hardware features of a production environment and software features.
Name the subtypes of Hardware Virtualization?
Full virtualization, Para-virtualization, and Emulation Virtualization.
What is Full Virtualization?
Entire underlying hardware is simulated. Guest OS is unaware and needs no modifications.
In full virtualization, is the guest OS completely isolated?
Yes.
What is Para-virtualization?
Hardware isn’t fully simulated; guest OS is aware and communicates with the hypervisor.
What are hypercalls used for?
To handle instructions at compile time.
In paravirtualization, is the guest OS completely isolated?
No.
What is Emulation Virtualization?
The virtual machine simulates the hardware and becomes independent of it.
What is Software Virtualization?
Creating and operating multiple virtual environments on a host machine.
What is the purpose of software virtualization?
To enable a complete computer system in order to allow the guest operating system to run.
Name the subtypes of Software Virtualization
Operating System Virtualization, Application Virtualization, and Service Virtualization.
What is Operating System Virtualization?
Hosting multiple OS on the native OS.
What is Application Virtualization?
Hosting individual applications in a virtual environment separate from the native OS.
What is Service Virtualization?
Hosting specific services related to a particular application.
What is Memory Virtualization?
Aggregating physical memory across different servers into a single virtualized memory pool.
What is the benefit of memory virtualization?
Enlarged contiguous working memory.
Name the subtypes of Memory Virtualization?
Application-level control and Operating system level control.
What is Application-level control?
Applications access the memory pool directly.
What is Operating system level control?
Access to the memory pool is provided through an operating system.
What is Storage Virtualization?
Grouping multiple physical storage devices and presenting them as a single storage unit.
What are the benefits of Storage Virtualization?
Easier to manage storage, improved performance, and reduced downtime.
Name the subtypes of Storage Virtualization?
Block Virtualization and File Virtualization.
What is Block Virtualization?
Storage capacity is made available to the operating system or the applications in the form of virtual disks.
What is File Virtualization?
The virtualisation entity provides virtual storage to the operating systems or applications in the form of files and directories.
What is Data Virtualization?
Presenting data as an abstract layer independent of data structure and database systems.
What is one of the benefits of Data Virtualization?
Decreases data input.
What is Network Virtualization?
Creating virtual networks within a physical network.
What are the benefits of Network Virtualization?
Improved security, reliability, and resource utilization.
Name the subtypes of Network Virtualization?
Internal network and External network.
What is Internal network virtualization?
Enables a single system to function like a network.
What is External network virtualization?
Consolidation of multiple networks into a single one, or segregation of a single network into multiple ones.
What is Desktop Virtualization?
Storing the user’s desktop on a remote server for access from any device/location.
List some benefits of Virtualization
*Easily outsource your hardware and eliminate any energy costs associated with its operation.
*The efficiency, security, and cost advantages.
*Run operating systems where the physical hardware is unavailable.
*Easier to create new machines, backup machines, etc.
*Software testing using “clean” installs of operating systems and software.
*Emulate more machines than are physically available.
*Timeshare lightly loaded systems on one host.
*Easy migration of virtual machines (shutdown needed or not).
What is one benefit of virtualization relating to hardware?
Easily outsource your hardware and eliminate any energy costs associated with its operation.
What is one benefit of virtualization relating to efficiency?
The efficiency, security, and cost advantages.
What is one benefit of virtualization relating to operating systems?
Run operating systems where the physical hardware is unavailable.
What is one benefit of virtualization relating to testing?
Software testing using “clean” installs of operating systems and software.
What is one benefit of virtualization relating to timeshare?
Timeshare lightly loaded systems on one host.
What is one benefit of virtualization relating to virtual machines?
Easy migration of virtual machines (shutdown needed or not).
What type of virtualization enables a single system to function like a network?
Internal Network Virtualization.
Q: What is VM provisioning?
The process of creating a new virtual machine on a physical server and allocating necessary computing resources.
How to Set Up a Virtual Machine Server
Choose a strong host server: Pick a multicore server with enough RAM and CPU.
Have storage ready: Make sure you have a place to store the virtual server images.
Use Hypervisor Software: Use software like VMware or Oracle VirtualBox to create the virtual server.
Pick a Network Connection: Choose how your virtual machine will connect to the network.
Ensure Power Supply: Make sure you have enough power to prevent the server from going down.
What are the two core services enabling users to get the best out of IaaS in cloud computing?
Virtual machine provisioning and migration services.
What was traditionally required to set up a new server before virtualization?
Checking inventory, getting a machine, formatting, installing OS and services, adding security patches.
How has virtualization improved server provisioning?
It allows provisioning in minutes using a self-service interface.
What is the benefit of VM migration?
Saves time, effort, ensures service availability, and meets SLA/SLO and QoS requirements.
How did server upgrades or maintenance work before virtualization?
They required significant time, effort, and cost due to complexity and dependencies.
How do hypervisors improve server migration?
They make maintenance, upgrades, and patches faster and easier.
: What does the virtualization layer do?
Partitions physical resources into multiple VMs and schedules resource allocation.
What are the benefits of virtualization?
High resource utilization, scalability, flexibility, and efficient management.
What is a private cloud?
A cloud within an organization for security and governance, offering public cloud-like functionality.
What is a Virtual Private Cloud (VPC)?
A private space within a cloud vendor’s data center dedicated to a company’s workloads.
What are key characteristics of a private cloud?
Self-service provisioning, automation, resource optimization, and workload support.
What is a hybrid cloud?
A mix of private and public clouds, enabling outsourcing of non-critical functions
What is cloud bursting?
Expanding workloads from a private cloud to a public cloud during high demand.
Why is standardization important in cloud computing?
It ensures interoperability among virtualization platforms and cloud services.
What is VMAN?
Virtualization Management Initiative by DMTF for interoperability and portability.
What does OVF (Open Virtualization Format) provide?
A common format for packaging and distributing virtual appliances.
What is OCCIWG (Open Cloud Computing Interface Working Group)?
A standard API initiative for cloud IaaS management and automation.
The virtual machine life cycle includes:
The virtual machine life cycle includes:
Request: A request is made to create a new server for a specific service.
Resource Pool: The IT department checks the available server resources.
Provisioning: The necessary virtual machine is provisioned.
Service Delivery: The VM provides the required service.
Release: The virtual machine is released, freeing up resources.
