4.1 Summarize Cloud-Computing Concepts
- Common Cloud Models
- Private Cloud
- Public Cloud
- Hybrid Cloud
- Community Cloud
- Infrastructure as a Service (IaaS)
- Software as a Service (SaaS)
- Platform as a Service (PaaS)
- Cloud Characteristics
- Shared Resources
- Metered Utilization
- Rapid Elasticity
- High Availability
- File Synchronization
- Desktop Virtualization
- Virtual Desktop Infrastructure (VDI) on Premises
- VDI in the Cloud
Cloud Models
What is the cloud? The cloud is a place where we can store and process our data without worrying about the underlying hardware. There are several types of cloud models
| IaaS | Infrastructure as a Service We rent physical infrastructure on an hourly/daily/monthly basis There are no upfront costs or hardware maintenance costs We do not pay for internet, power, heating, cooling, etc. We have access to each system hardware component and are responsible for configuring them. Examples include Amazon Web Services and Microsoft Azure |
| SaaS | Software as a Service We are paying for the right to use a software application The software is licensed on a per hour or per month basis. The software is centrally hosted. We do not manage the software code, hardware, or licenses. Example includes Salesforce |
| PaaS | Platform as a Service Hybrid service between IaaS and SaaS A “platform” is licensed per hour or per month. We do not manage hardware directly. The hardware is an abstract concept that we can use to run any application we want. The advantage of PaaS is the ability to run applications without having to build the underlying infrastructure. |
| Public Cloud | A public cloud one that is available to the general public. The resources inside a public cloud are shared amongst all customers, which improves efficiency and reduces cost. Multiple customers may be present on the same physical server without realizing it (cloud software is supposed to prevent data leaks between customers) The public cloud has risks and some users choose to have their applications run on dedicated hardware |
| Private Cloud | A private cloud is built by one organization for its internal use. A large organization can use a private cloud to share resources amongst different departments. The private cloud improves efficiency because multiple departments can share the same hardware |
| Hybrid Cloud | The hybrid cloud is a mix of a private cloud and a public cloud. A company may decide that some applications are too sensitive to host on a public cloud, or that some applications will not run properly when they are off site but would like to take advantage of the public cloud. Applications that can run on the public cloud are placed there, and remaining applications are placed on a private cloud. The private cloud and public cloud are connected via a WAN or VPN. They act like they are part of the same physical network. |
| Community Cloud | A community cloud is like a private cloud except that infrastructure is shared by several organizations. For example, a city can set up a private cloud. The fire department uses part of it, the water works uses part of it, and the police department uses part of it. |
Cloud Benefits
There are five essential characteristics of a cloud computing service
- On-demand self service
- Broad network access
- Resource pooling
- Rapid elasticity
- Measured service
| Shared Resources | The cloud must allow multiple users to share computer resources, including File storage Databases Processing Network connectivity |
| Rapid Elasticity | The cloud must have the ability to instantly add or remove capacity. A resource can scale on demand. Scaling can happen automatically (via a script that detects an overload) or manually at the request of a user. |
| On-Demand | A user can obtain cloud services “on demand” from a control panel |
| Resource Pooling | Resources are shared across multiple customers. When a resource is released by one customer, it can be allocated to another |
| Measured Services | The cloud provider can measure the quantity of services used by each customer. A user is billed for resources that he or she consumes. |
| Metered | A cloud provider can meter or limit the amount of resources a user can use. This is important because a user could request too many resources at once, which could impact other customers. |
| High Availability | The cloud must have a high level of availability. This is achieved by having multiple levels of hardware redundancy, and multiple data centers in different geographic locations. |
| File Synchronization | The cloud must synchronize user files across multiple locations and multiple redundant systems. Files that are placed on one system should be instantly available on other systems. |
Off-Site E-mail Applications
There are three main cloud e-mail services
| G Suite | Provided by Google Billed on a per-user per-month license Includes the following services -E-mail (Gmail) -File Sharing (Google Drive) -Calendar (Google Calendar) -Hangouts (Chat and Collaboration) E-mail can be accessed via a web app or via an e-mail client, such as Outlook |
| Exchange | Provided by Microsoft Billed on a per-user per-month license E-mail can be accessed via a web app or via an e-mail client, such as Outlook |
| Office 365 | Provided by Microsoft Billed on a per-user per-month license Includes all the features of Exchange plus each user can install Office 365 on up to five devices Includes -Office 365 includes Excel, Word, Outlook, PowerPoint, Access, and Skype -Teams allows users to communicate via messaging, voice, and video -Store files in the cloud with OneDrive -SharePoint allows a company to create internal websites Additional features -eDiscovery -Integration with active directory -Data Leak Prevention -Message encryption |
Cloud Storage
There are five main cloud storage services
| Google Drive | Provided by Google Free for personal use Pay for business use on a per-user per month basis (integrates with Google Workspaces) Files are available through a web interface Can share files and folders with internal and external users |
| One Drive | Provided by Microsoft Free for personal use Pay for business use on a per-user per month basis (integrated with Office 365) Files are available through a web interface, and through a downloadable app Allows you to sync files between your computer and the cloud Can share files and folders with internal and external users |
| SharePoint | Provided by Microsoft Pay per-user per-month Available with an Office 365 business license Allows you to create internal corporate websites, accessible through a web interface Can share files and folders with internal and external users |
| Amazon WorkDocs | Provided by Amazon Web Services Pay per-user per-month Files are available through a web interface, and through a downloadable app Allows you to sync files between your computer and the cloud Can share files and folders with internal and external users |
| Dropbox / Box | Cloud apps that provide file sharing Free for personal use Pay for business use Can share files and folders with internal and external users |
Virtual Application Streaming/Cloud-Based Applications/Virtual Desktops
A virtual desktop is a concept where we open a remote session with a server, and we run the applications on the server. Nothing runs on our physical computer. We can disconnect our session and reconnect it on the same computer or another computer, and our applications will be just like we left them.
Why do we want to do this?
- We can use cheaper local hardware because we are not running any applications on it.
- The data is stored on a remote server, which can be on a secure location. The local hardware will not contain any sensitive data.
- A single server can support dozens or hundreds of users.
- It is easier to upgrade applications on a single server than on many user desktops
There are a few ways to deliver virtual desktops
| Citrix | Citrix creates a system called “application virtualization”. Itallows a user to run an application regardless of the type of computer system he is using How? The application runs on a Citrix serverThe user runs a “plug in” on his computer that connects to the serverThe server streams the application through the plugin to the user over the internetWe call this concept “containerization” because the user only receives the specific resources he needs to run the application Advantages Application will operate on any type of computer Application data is stored centrally on Citrix server and can be backed up easily Disadvantages Requires internet to function There are licensing costs associated with Citrix |
| Amazon WorkSpaces | WorkSpaces is a Cloud Desktop Service User “desktops”, files, applications, and computing resources are stored in the Amazon cloud A user can install the WorkSpaces client on their Windows, iOS, Apple, or Android device and connect to their desktop The desktop is in the cloud, so a user can connect to it from multiple locations, and begin working where they left off It is easy to back up the WorkSpaces, even while they are in use Integrates with Active Directory and other authentication protocols WorkSpaces allows a customer to scale a desktop to hundreds or thousands of users instantly Customer is billed for each WorkSpace in use on an hourly basis; customer is only billed for WorkSpaces when they are actually in use A user must have access to the internet to use WorkSpaces |
| Remote Desktop Services | Remote Desktop Services (RDP) is a feature of the Microsoft Server Operating System A central server stores user desktops, applications, and settings The server can be hosted in the cloud or on premises, but must stay operating to facilitate user access If we put the RDP service in the cloud, then we must have a reliable, low latency internet connection A user can connect to the server via a Remote Desktop Protocol from any Windows device RDP requires a per-user license (CAL) to access the server |