Cloud and Data Center Technologies (4361602) - Winter 2024 Solution

Question 1(a) [3 marks]

#

Define cloud computing and state it’s desirable features.

Answer:

Cloud Computing is a technology that delivers computing services like servers, storage, databases, and software over the internet, allowing users to access resources on-demand without owning physical infrastructure.

Desirable Features:

Mnemonic: “On-Demand Broad Resources Rapidly Measured”

Question 1(b) [4 marks]

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Draw and explain cloud architecture.

Answer:

graph TB
    A[Client Layer<br/>Web Browser, Mobile Apps] --> B[Internet]
    B --> C[Cloud Service Provider]
    C --> D[Frontend Platform<br/>User Interface]
    D --> E[Backend Platform]
    E --> F[IaaS - Infrastructure]
    E --> G[PaaS - Platform]
    E --> H[SaaS - Software]
    F --> I[Physical Infrastructure<br/>Servers, Storage, Network]

Cloud Architecture Components:

• Client Layer: End-user devices accessing cloud services
• Internet: Network connection medium
• Frontend: User interface and service management
• Backend: Core processing and resource management
• Service Models: IaaS, PaaS, SaaS layers
• Physical Infrastructure: Hardware resources in data centers

Mnemonic: “Clients Connect Through Frontend Backend Services Infrastructure”

Question 1(c) [7 marks]

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Explain the cloud service models in detail.

Answer:

Detailed Explanation:

• IaaS (Infrastructure as a Service): Provides virtualized computing resources including virtual machines, storage, and networking. Users have complete control over operating systems and applications.

• PaaS (Platform as a Service): Offers a development platform with programming tools, database management, and middleware. Developers focus on application logic without infrastructure management.

• SaaS (Software as a Service): Delivers complete applications over the internet. Users simply access the software through web browsers without installation or maintenance.

Mnemonic: “Infrastructure Platforms Software - Increasing Abstraction”

Question 1(c OR) [7 marks]

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Explain service level agreement (SLA) in cloud computing with example.

Answer:

Service Level Agreement (SLA) is a contract between cloud service provider and customer that defines the expected level of service, performance metrics, and penalties for non-compliance.

Key Components:

Example - AWS SLA:

• EC2 SLA: 99.99% monthly uptime
• S3 SLA: 99.9% availability, 99.999999999% durability
• Penalty: 10% service credit if availability drops below threshold

Benefits:

• Accountability: Clear expectations for both parties
• Quality assurance: Guaranteed service levels
• Risk mitigation: Compensation for service failures

Mnemonic: “Availability Performance Security Support Penalties”

Question 2(a) [3 marks]

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Define virtualization. Give characteristics of virtualization.

Answer:

Virtualization is a technology that creates virtual versions of computing resources like servers, storage, or networks, allowing multiple virtual instances to run on single physical hardware.

Characteristics:

• Resource sharing: Multiple VMs share physical hardware efficiently
• Isolation: Virtual machines operate independently without interference
• Portability: VMs can be moved between different physical hosts
• Scalability: Resources can be allocated dynamically as needed
• Cost efficiency: Reduces hardware requirements and operational costs

Mnemonic: “Resources Isolated Portable Scalable Cost-effective”

Question 2(b) [4 marks]

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Distinguish between paravirtualization and full virtualization.

Answer:

Key Differences:

• Paravirtualization requires guest OS to be aware of virtualization and cooperate with hypervisor
• Full Virtualization completely emulates hardware, making guest OS unaware of virtualization

Mnemonic: “Para Cooperates, Full Emulates”

Question 2(c) [7 marks]

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Define hypervisors. Explain Type 1 and Type 2 hypervisors.

Answer:

Hypervisor is software that creates and manages virtual machines by abstracting physical hardware and allocating resources to multiple VMs.

graph TB
    subgraph "Type 1 Hypervisor"
        A1[VM1] 
        A2[VM2]
        A3[VM3]
        A4[Type 1 Hypervisor<br/>Bare Metal]
        A5[Physical Hardware]
        A1 --> A4
        A2 --> A4
        A3 --> A4
        A4 --> A5
    end
    
    subgraph "Type 2 Hypervisor"
        B1[VM1]
        B2[VM2]
        B3[Type 2 Hypervisor<br/>Hosted]
        B4[Host Operating System]
        B5[Physical Hardware]
        B1 --> B3
        B2 --> B3
        B3 --> B4
        B4 --> B5
    end

Comparison:

Type 1 Advantages: Better performance, direct hardware access, enterprise-grade security Type 2 Advantages: Easier setup, runs alongside host OS, good for development

Mnemonic: “Type 1 Bare Metal, Type 2 Hosted”

Question 2(a OR) [3 marks]

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List out types of virtualization and explain any one in brief.

Answer:

Types of Virtualization:

• Server Virtualization
• Storage Virtualization
• Network Virtualization
• Desktop Virtualization
• Application Virtualization
• Memory Virtualization

Server Virtualization (Detailed): Server virtualization creates multiple virtual servers on single physical server. Each virtual server operates independently with its own operating system and applications.

Benefits:

• Resource optimization: Better hardware utilization
• Cost reduction: Fewer physical servers needed
• Flexibility: Easy VM migration and scaling

Mnemonic: “Server Storage Network Desktop Application Memory”

Question 2(b OR) [4 marks]

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Describe hardware and software virtualization.

Answer:

Hardware Virtualization: Leverages CPU virtualization extensions to directly execute guest instructions, providing better performance and security isolation.

Software Virtualization: Uses binary translation to convert guest instructions to host-compatible instructions, offering broader compatibility but with performance overhead.

Mnemonic: “Hardware Fast, Software Compatible”

Question 2(c OR) [7 marks]

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Explain the process of creating and managing virtual machines.

Answer:

VM Creation Process:

flowchart TD
    A[Plan VM Requirements] --> B[Select Hypervisor Platform]
    B --> C[Allocate Resources<br/>CPU, RAM, Storage]
    C --> D[Create Virtual Disk]
    D --> E[Configure Network Settings]
    E --> F[Install Guest OS]
    F --> G[Install VM Tools/Drivers]
    G --> H[Configure VM Settings]
    H --> I[Create VM Snapshot]

Detailed Steps:

1. Planning: Determine CPU cores, RAM, storage, and network requirements
2. Resource Allocation: Assign physical resources to virtual machine
3. Storage Setup: Create virtual disks (VMDK, VHD, QCOW2 formats)
4. Network Configuration: Set up virtual network adapters and connectivity
5. OS Installation: Install operating system using ISO or network boot
6. Tools Installation: Install hypervisor-specific tools for better integration
7. Management Tasks: Monitor performance, create snapshots, backup VMs

VM Management Operations:

• Start/Stop/Restart: Power operations
• Snapshot Management: Create, restore, delete snapshots
• Resource Scaling: Add/remove CPU, memory, storage
• Migration: Move VMs between hosts
• Backup/Recovery: Data protection strategies

Mnemonic: “Plan Select Allocate Create Configure Install Manage”

Question 3(a) [3 marks]

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Define Data Center. Describe any two types of data centers.

Answer:

Data Center is a facility that houses computer systems, networking equipment, and storage systems along with supporting infrastructure like power, cooling, and security systems.

Types of Data Centers:

Enterprise Data Center:

• Built and managed by organization for internal use
• Complete control over infrastructure and security
• Higher initial investment but customized solutions

Colocation Data Center:

• Third-party facility providing space, power, and cooling
• Multiple organizations share common infrastructure
• Lower costs and professional management

Mnemonic: “Enterprise Private, Colocation Shared”

Question 3(b) [4 marks]

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Differentiate between scalability and elasticity in cloud data center.

Answer:

Key Differences:

• Scalability focuses on capacity to grow, while Elasticity emphasizes automatic adjustment
• Scalability requires human intervention, Elasticity is automated
• Scalability is strategic planning, Elasticity is operational efficiency

Examples:

• Scalability: Adding more servers during expected traffic increase
• Elasticity: Auto-scaling groups that add/remove instances based on CPU usage

Mnemonic: “Scalability Plans, Elasticity Adapts”

Question 3(c) [7 marks]

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Explain SDN (Software-Defined Networking) in data center with diagram.

Answer:

graph TB
    subgraph "SDN Architecture"
        A[Applications Layer<br/>Network Apps, Services]
        B[Control Layer<br/>SDN Controller<br/>OpenFlow Protocol]
        C[Infrastructure Layer<br/>OpenFlow Switches]
        D[Physical Network Infrastructure]
        
        A -.->|Northbound API| B
        B -.->|Southbound API<br/>OpenFlow| C
        C --> D
    end

SDN Components:

Key Features:

• Centralized Control: Single point of network management
• Programmability: Network behavior defined through software
• Abstraction: Separation of control and data planes
• Dynamic Configuration: Real-time network policy changes

Benefits in Data Centers:

• Flexibility: Easy network configuration changes
• Automation: Programmable network management
• Cost Reduction: Commodity hardware usage
• Innovation: Rapid deployment of new services

Mnemonic: “Applications Control Infrastructure - Programmable Networks”

Question 3(a OR) [3 marks]

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Identify and describe the key components of a data center.

Answer:

Key Data Center Components:

• Servers: Computing resources running applications and services
• Storage Systems: Data storage arrays (SAN, NAS, DAS)
• Network Equipment: Switches, routers, load balancers for connectivity
• Power Infrastructure: UPS, generators, PDUs for reliable power
• Cooling Systems: HVAC systems maintaining optimal temperature
• Security Systems: Physical and logical access controls

Critical Infrastructure: Each component is essential for data center operation, with redundancy built-in for high availability and disaster recovery.

Mnemonic: “Servers Store Network Power Cool Secure”

Question 3(b OR) [4 marks]

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List data center network topologies and explain any one of them.

Answer:

Data Center Network Topologies:

• Three-tier Architecture
• Spine-Leaf Architecture
• Fat Tree Topology
• Mesh Topology

Spine-Leaf Architecture (Detailed):

Characteristics:

• Leaf switches connect to servers and storage
• Spine switches provide inter-leaf connectivity
• No leaf-to-leaf connections - all traffic goes through spine
• Equal path lengths between any two endpoints
• High bandwidth and low latency design

Mnemonic: “Three Spine Fat Mesh”

Question 3(c OR) [7 marks]

#

Explain Infrastructure as Code (IaC) with its popular automation tools.

Answer:

Infrastructure as Code (IaC) is the practice of managing and provisioning computing infrastructure through machine-readable definition files rather than manual processes.

Key Principles:

Popular IaC Tools:

IaC Benefits:

• Speed: Faster deployment and scaling
• Consistency: Identical environments across stages
• Cost Control: Resource optimization and tracking
• Reliability: Reduced configuration drift
• Collaboration: Shared infrastructure definitions

Implementation Example:

# Terraform example
resource "aws_instance" "web_server" {
  ami           = "ami-12345678"
  instance_type = "t2.micro"
  tags = {
    Name = "WebServer"
  }
}

Mnemonic: “Terraform Ansible CloudFormation Puppet Chef”

Question 4(a) [3 marks]

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Define cloud storage. Write example of cloud storage services.

Answer:

Cloud Storage is a service that allows users to store, access, and manage data on remote servers over the internet instead of local storage devices.

Examples of Cloud Storage Services:

Key Benefits: Accessibility, scalability, cost-effectiveness, automatic backup

Mnemonic: “Amazon Google Microsoft Dropbox Apple”

Question 4(b) [4 marks]

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Differentiate between data consistency and durability.

Answer:

Data Consistency: Ensures all database nodes contain identical data at any given time, crucial for applications requiring real-time accuracy.

Data Durability: Guarantees that committed data remains available even after system crashes, power failures, or hardware malfunctions.

Trade-offs: Strong consistency may impact performance, while high durability requires additional storage costs.

Mnemonic: “Consistency Synchronizes, Durability Survives”

Question 4(c) [7 marks]

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Explain types of cloud storage in detail.

Answer:

Detailed Explanation:

Object Storage:

• Structure: Flat namespace with unique object identifiers
• Scalability: Virtually unlimited capacity
• Access: REST APIs, web interfaces
• Benefits: Cost-effective, globally accessible, metadata support

Block Storage:

• Structure: Raw storage blocks attached to compute instances
• Performance: High IOPS, low latency
• Access: Direct block-level access
• Benefits: High performance, database optimization

File Storage:

• Structure: Traditional directory/folder hierarchy
• Sharing: Multi-user concurrent access
• Access: Standard file system protocols (NFS, SMB)
• Benefits: Familiar interface, application compatibility

Selection Criteria:

• Performance requirements: Block for databases, Object for web
• Access patterns: File for shared access, Object for web apps
• Cost considerations: Object cheapest, Block most expensive

Mnemonic: “Objects Scale, Blocks Perform, Files Share”

Question 4(a OR) [3 marks]

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Define cloud databases. Write example of cloud database services.

Answer:

Cloud Databases are database services hosted and managed by cloud providers, offering scalability, high availability, and reduced administration overhead.

Examples of Cloud Database Services:

Benefits: Automatic scaling, backup management, security updates, global availability

Mnemonic: “Amazon Google Microsoft MongoDB”

Question 4(b OR) [4 marks]

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Describe data scaling and replication.

Answer:

Data Scaling:

Data Replication:

Key Benefits:

• Scaling: Handle increased load and data volume
• Replication: Improve availability and disaster recovery
• Performance: Distribute load across multiple systems
• Fault Tolerance: Continue operations despite failures

Mnemonic: “Vertical Horizontal, Master Slave Peer”

Question 4(c OR) [7 marks]

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Explain types of cloud databases.

Answer:

SQL vs NoSQL Comparison:

Selection Criteria:

• Data Structure: Structured data → SQL, Unstructured → NoSQL
• Scalability: Horizontal scaling → NoSQL
• Consistency: Strong consistency → SQL
• Complexity: Complex queries → SQL, Simple access → NoSQL

Cloud Database Services:

• Amazon: RDS (SQL), DynamoDB (NoSQL), DocumentDB (Document)
• Google: Cloud SQL, Firestore, BigTable
• Microsoft: Azure SQL, Cosmos DB

Mnemonic: “Relational Document Key Column Graph”

Question 5(a) [3 marks]

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Define cloud security. List out various Challenges for Cloud Security.

Answer:

Cloud Security refers to the policies, technologies, applications, and controls utilized to protect virtualized IP, data, applications, services, and infrastructure associated with cloud computing.

Cloud Security Challenges:

• Data breaches and privacy concerns
• Identity and access management complexity
• Insider threats and privileged user access
• Compliance and regulatory requirements
• Shared responsibility model confusion
• API security vulnerabilities

Key Challenge Areas: Each challenge requires specific security strategies and tools to mitigate risks and ensure data protection in cloud environments.

Mnemonic: “Data Identity Insider Compliance Shared API”

Question 5(b) [4 marks]

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Write a short note on Identity Management and Access Control.

Answer:

Identity and Access Management (IAM):

Access Control Models:

• Role-Based Access Control (RBAC): Users assigned roles with specific permissions
• Attribute-Based Access Control (ABAC): Dynamic permissions based on attributes
• Mandatory Access Control (MAC): System-enforced security policies

Best Practices:

• Principle of least privilege: Minimum necessary access
• Multi-factor authentication: Enhanced security verification
• Regular access reviews: Periodic permission audits
• Zero trust model: Verify every access request

Mnemonic: “Authenticate Authorize Account”

Question 5(c) [7 marks]

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Explain the technologies used for data security in cloud.

Answer:

Security Implementation Layers:

graph TD
    A[Application Security<br/>Code security, input validation] 
    B[Data Security<br/>Encryption, tokenization]
    C[Network Security<br/>Firewalls, VPN, SSL/TLS]
    D[Infrastructure Security<br/>Physical security, hypervisor]
    
    A --> B --> C --> D

Key Security Practices:

• Data at Rest: Encrypt stored data using strong encryption algorithms
• Data in Transit: Secure transmission using TLS/SSL protocols
• Data in Use: Protect data during processing with secure enclaves
• Key Rotation: Regular cryptographic key updates
• Compliance: Meet regulatory requirements (GDPR, HIPAA, SOX)

Emerging Technologies:

• Homomorphic Encryption: Compute on encrypted data
• Zero-Knowledge Proofs: Verify without revealing data
• Confidential Computing: Protect data during processing

Mnemonic: “Encrypt Keys Sign Control Network Prevent Backup”

Question 5(a OR) [3 marks]

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Define serverless computing. List out advantages of serverless computing.

Answer:

Serverless Computing is a cloud execution model where cloud providers dynamically manage server allocation and scaling, allowing developers to focus solely on code without server management.

Advantages of Serverless Computing:

• No server management: Cloud provider handles infrastructure
• Automatic scaling: Scales up/down based on demand automatically
• Pay-per-use pricing: Only pay for actual execution time
• Faster development: Focus on business logic, not infrastructure
• High availability: Built-in fault tolerance and redundancy
• Reduced operational overhead: No patching, monitoring servers

Popular Examples: AWS Lambda, Azure Functions, Google Cloud Functions

Mnemonic: “No Automatic Pay Faster High Reduced”

Question 5(b OR) [4 marks]

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Differentiate between edge and fog computing.

Answer:

Key Differences:

• Edge brings compute directly to data source
• Fog creates a distributed computing layer
• Edge optimizes for immediate response
• Fog provides broader area coverage

Benefits of Both:

• Reduced bandwidth usage to cloud
• Improved response times
• Enhanced privacy and security
• Better reliability for critical applications

Mnemonic: “Edge Direct, Fog Distributed”

Question 5(c OR) [7 marks]

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Define Containers. Explain steps to create image and execute the docker container with example.

Answer:

Containers are lightweight, portable packages that include application code, runtime, system tools, libraries, and settings needed to run an application consistently across different environments.

Docker Container Creation Steps:

flowchart TD
    A[Write Dockerfile] --> B[Build Docker Image]
    B --> C[Run Docker Container]
    C --> D[Manage Container Lifecycle]
    
    A1[FROM base_image<br/>COPY app_files<br/>RUN install_commands<br/>CMD start_command] --> A
    B1[docker build -t image_name .] --> B
    C1[docker run -p port:port image_name] --> C
    D1[docker ps<br/>docker stop<br/>docker start] --> D

Step-by-Step Process:

1. Create Dockerfile:

# Base image
FROM node:14-alpine

# Set working directory
WORKDIR /app

# Copy package files
COPY package*.json ./

# Install dependencies
RUN npm install

# Copy application code
COPY . .

# Expose port
EXPOSE 3000

# Start command
CMD ["npm", "start"]

2. Build Docker Image:

# Build image from Dockerfile
docker build -t my-web-app:latest .

# List images
docker images

3. Run Docker Container:

# Run container with port mapping
docker run -d -p 8080:3000 --name web-app my-web-app:latest

# Check running containers
docker ps

4. Container Management:

Container Benefits:

• Portability: Run anywhere Docker is installed
• Consistency: Same environment across development/production
• Isolation: Applications run independently
• Efficiency: Share OS kernel, lightweight compared to VMs
• Scalability: Easy horizontal scaling with orchestration

Docker vs VM Comparison:

Common Docker Commands:

• Image Management: docker pull, docker push, docker rmi
• Container Operations: docker create, docker kill, docker rm
• System Info: docker info, docker version, docker system df

Example Use Case: A web application with Node.js backend can be containerized to ensure consistent deployment across development, testing, and production environments, eliminating “works on my machine” issues.

Container Orchestration: For production deployments, use orchestration tools like:

• Kubernetes: Advanced container orchestration
• Docker Swarm: Native Docker clustering
• Amazon ECS: AWS container service

Mnemonic: “Create Build Run Manage - Dockerfile Commands Lifecycle”