Midterm Topics
Basics of Cloud Computing
Cloud computing refers to the delivery of computing services (e.g., servers, storage, databases, networking, software) over the internet ("the cloud"). It eliminates the need for owning physical hardware and allows access to resources on demand.
Key Components
Infrastructure as a Service (IaaS)
Provides virtualized computing resources (e.g., virtual machines, storage).
Example: AWS EC2, Microsoft Azure Virtual Machines.
Platform as a Service (PaaS)
Offers a platform for developers to build, test, and deploy applications.
Example: Google App Engine, AWS Elastic Beanstalk.
Software as a Service (SaaS)
Delivers software applications over the internet.
Example: Gmail, Dropbox, Microsoft Office 365.
Types of Cloud Deployment Models
Public Cloud: Resources shared among multiple users (e.g., AWS, Google Cloud).
Private Cloud: Dedicated resources for one organization.
Hybrid Cloud: Combination of public and private clouds.
Community Cloud: Shared infrastructure for specific communities or organizations.
Key Features
On-Demand Availability: Resources can be accessed as needed.
Scalability: Easily scale resources up or down.
Pay-as-You-Go: Pay only for what you use.
Accessibility: Accessible from anywhere via the internet.
Benefits of Cloud Computing
Cost Savings: Reduces hardware and maintenance costs.
Flexibility: Adapts to changing business needs.
Reliability: Ensures high availability and disaster recovery.
Collaboration: Enables teams to work together from different locations.
Examples of Cloud Computing Services
AWS (Amazon Web Services): Offers a wide range of cloud services for computing, storage, and networking.
Google Cloud Platform (GCP): Provides tools for machine learning, data analytics, and cloud hosting.
Microsoft Azure: Known for its integration with Microsoft products.
Cloud computing is transforming the way organizations and individuals use technology, offering scalable, secure, and cost-effective solutions.
History of Cloud Computing
1. Early Foundations (1960s)
Concept Origin: John McCarthy envisioned computing as a utility, similar to water or electricity.
Mainframe and Terminals: Centralized computing systems allowed multiple users to access a mainframe using terminals.
Key Idea: Shared resource utilization through time-sharing.
2. Emergence of Virtualization (1970s)
Breakthrough: IBM introduced virtualization with the Virtual Machine (VM) concept.
Impact: Enabled multiple operating systems to run on a single physical machine.
3. Networking and the Internet (1980s-1990s)
ARPANET to the Internet: Evolution of networking enabled global connectivity.
Client-Server Model: Shift from mainframes to distributed computing.
Application Hosting: Companies began hosting software and applications for others (precursor to SaaS).
4. Rise of Modern Cloud Computing (2000s)
Amazon Web Services (AWS): Launched in 2006, introduced Elastic Compute Cloud (EC2).
Significance: Offers scalable, on-demand computing resources.
Google and Microsoft: Entered the market with Google App Engine (2008) and Microsoft Azure (2010).
5. Growth and Diversification (2010s-Present)
Widespread Adoption: Cloud used across industries for storage, computing, AI, and big data.
Hybrid and Multi-Cloud: Organizations began using combinations of public, private, and hybrid clouds.
Edge Computing: Brought computation closer to data sources for reduced latency.
6. Key Milestones
2008: Dropbox introduced cloud storage for personal users.
2011: Apple launched iCloud for syncing devices.
2020s: Cloud becomes essential for remote work, digital transformation, and AI development.
The evolution of cloud computing reflects advancements in networking, virtualization, and distributed systems, revolutionizing how businesses and individuals manage data and services.
Cloud Computing Deployment Models
Cloud computing deployment models define how cloud services are hosted, accessed, and managed. The four main models are:
1. Public Cloud
What it is: Services are provided over the internet and shared across multiple users.
Ownership: Managed by third-party vendors like AWS, Microsoft Azure, or Google Cloud.
Examples:
Hosting a website using AWS EC2.
Using services like Gmail or Google Drive.
Pros: Cost-efficient, highly scalable, and accessible globally.
Cons: Limited control and potential security risks.
2. Private Cloud
What it is: Infrastructure dedicated solely to one organization, either hosted on-site or by a provider.
Ownership: Operated by the organization or a third party.
Examples:
A bank using a private cloud for financial operations.
A government agency managing sensitive data.
Pros: High security, full control, and regulatory compliance.
Cons: High setup costs and less scalability.
3. Hybrid Cloud
What it is: Combines public and private clouds, allowing seamless movement of data and applications between them.
Ownership: Shared between an organization and a cloud provider.
Examples:
An e-commerce platform using private cloud for customer data and public cloud for handling traffic spikes.
Pros: Flexible, scalable, and cost-efficient.
Cons: Complex to manage and synchronize data.
4. Community Cloud
What it is: A shared infrastructure used by organizations with similar interests or requirements.
Ownership: Managed collectively or by a third party.
Examples:
Universities sharing cloud resources for research.
Hospitals collaborating on a patient management system.
Pros: Cost sharing, better collaboration, and compliance support.
Cons: Limited availability and flexibility compared to other models.
Virtualization Explained
Virtualization refers to creating virtual versions of physical resources like servers, storage, or networks. It allows multiple systems or applications to run on a single physical resource, improving efficiency and flexibility.
Key Points:
What is Virtualization?
Technology that abstracts physical resources into virtual instances.
Enables multiple operating systems and applications to run on the same hardware.
2. Types of Virtualization
Server Virtualization:
Divides a physical server into multiple virtual servers.
Example: VMware ESXi allows running multiple virtual machines (VMs) on a single server.
Desktop Virtualization:
Creates virtual desktops that users can access remotely.
Example: Citrix Virtual Desktops provide remote desktop access to employees.
Network Virtualization:
Abstracts network resources into virtual networks for better management.
Example: VLANs (Virtual Local Area Networks) separate network traffic for security.
Storage Virtualization:
Combines multiple storage devices into a single virtual storage unit.
Example: Storage Area Networks (SANs) use virtualized storage for efficient data management.
Application Virtualization:
Separates an application from the underlying OS.
Example: Windows Virtual Desktop allows running applications without installing them locally.
3. Advantages of Virtualization
Cost Efficiency: Reduces hardware costs by consolidating resources.
Scalability: Allows easy addition of resources without physical upgrades.
Flexibility: Supports multiple environments on a single machine.
Disaster Recovery: Simplifies backup and recovery with virtual snapshots.
4. Examples in Real Life
Amazon Web Services (AWS): Uses virtualization to deliver cloud computing resources.
VMware Workstation: Lets users create virtual machines on their desktop.
Hyper-V by Microsoft: Enables running multiple operating systems on a Windows server.
Virtualization transforms resource management by maximizing efficiency, flexibility, and scalability.
Characteristics of Cloud Computing
1. On-Demand Self-Service
Users can provision resources like servers or storage as needed without requiring human intervention from service providers.
Example: Launching a virtual machine in AWS or Azure with a few clicks.
2. Broad Network Access
Accessible over the internet from any device (laptop, mobile, or tablet).
Promotes accessibility and mobility for users.
Example: Accessing Google Drive or Dropbox from anywhere.
3. Resource Pooling
Resources are shared among multiple users through a multi-tenant model.
Enables efficient allocation of storage, processing power, and bandwidth.
Example: Data centers hosting multiple clients’ services on shared hardware.
4. Rapid Elasticity
Resources can be scaled up or down automatically or manually based on demand.
Supports handling sudden workload changes efficiently.
Example: E-commerce websites scaling during a Black Friday sale.
5. Measured Service (Pay-as-You-Go)
Usage is monitored, measured, and billed based on consumption.
Ensures cost efficiency by charging only for resources used.
Example: Paying for storage used in Google Cloud Storage.
6. High Availability and Reliability
Ensures continuous availability of services with minimal downtime.
Uses redundant systems and disaster recovery mechanisms.
Example: Cloud-hosted applications with uptime guarantees of 99.9%.
7. Scalability and Flexibility
Easily adapts to growing or shrinking workloads without the need for physical upgrades.
Supports both horizontal (adding more machines) and vertical scaling (upgrading resources).
Example: Auto-scaling features in AWS.
8. Security
Offers advanced security features like encryption, firewalls, and identity management.
Ensures data protection and compliance with regulations.
Example: Multi-factor authentication in Microsoft Azure.
9. Global Reach
Cloud providers have data centers worldwide, enabling users to deploy applications closer to their customers.
Example: Content Delivery Networks (CDNs) improve performance by serving content globally.
10. Cost Efficiency
Reduces the need for investing in physical infrastructure.
Converts capital expenditure (CapEx) into operational expenditure (OpEx).
Example: Startups using cloud hosting instead of building data centers.
These characteristics make cloud computing a flexible, efficient, and reliable solution for businesses and individuals.