Advanced System Analysis Lecture 9: Architecture Design

Advanced System Analysis Lecture (9) - Chapter 5: Architecture Design

• Lecture (9) covered chapter 5 on architecture design for advanced system analysis.
• Lectures were by Dr. Asmaa Mohamed.

Less Commonly Used Architectures

• Less commonly used architectural designs were discussed.

Server-Based Architectures

• Early computing architectures were server-based.
• The server (often a central mainframe) handled all application functions.
• Clients (typically terminals) facilitated communication with the server.
• The server managed presentation, application, data access and storage logic.

Server-Based Architectures Advantages

• Application software and data are centrally stored on the server.
• Control is centralized, as all messages flow through the server.
• Software development and administration are simplified by the central computer hosting the entire system.

Server-Based Architectures Disadvantages

• The server in early systems processed all work, which generated bottlenecks and slow response times as the load increased.
• Demands from applications and increasing users overloaded the server.
• Response times slowed down, and server upgrades became increasingly costly.

Zero Client Server or Ultrathin Client

• A modern server-based computing model often used in virtual desktop infrastructure (VDI).
• A VDI environment hosts a desktop operating system (like Windows or Linux) on a centralized, remote server.
• End-user data and desktop images are managed within a virtual machine.
• Zero Client endpoint devices are small, powerful hardware units that reduce spending, power consumption, space, noise and security concerns.
• Typical device connects to a remote server. The server hosts the OS, applications and software.
• Server based zero-client model limits non-business use of the client computer (e.g., no social media use).

Zero Client Server Benefits

• Significant power usage reduction compared to traditional client configurations.
• Devices are less expensive than traditional PCs and Thin Client devices.
• No vulnerabilities to malware due to the lack of software on the client device.
• Efficient and secure application delivery to end-users.
• Easy administration of multiple virtual PCs on server-class hardware, reducing physical PC acquisition and maintenance costs.

Client-Based Architectures

• In client-based architectures clients (microcomputers) share a local area network.
• The client computers handle presentation, application, and data access logic.
• The server provides storage for data.

Client-Based Architectures Advantages

• Simple architecture suitable for situations with low user numbers and minimal data access needs.

Client-Based Architectures Problems

• All data on the server must travel to the client for processing. This can overload both the network and client computers, especially with large databases and numerous user queries.
• Data access logic is executed on the client, requiring the entire database to be transmitted before processing.

Advances in Architecture Configurations

• Two significant advances are virtualization and cloud computing.

Virtualization

• Virtualization creates virtual devices or resources (e.g., servers, storage) as software-based versions, offering flexibility and efficiency.
• Types of virtualization include server virtualization, storage virtualization, and network virtualization.
• Server virtualization involves partitioning a physical server into several virtual servers.
• Server virtualization can significantly reduce costs by minimizing the need for large, monolithic computers.
• Storage virtualization pools physical storage from multiple network devices to create a single, manageable storage entity.
• Network virtualization combines network resources by splitting bandwidth into channels that can be assigned or reassigned dynamically to specific servers in real-time.

Capabilities of Server Virtualization

• It overcomes limitations of old server-based architectures, which were based on single, large, expensive computers.
• Reduced hardware requirements translates to lower costs.

Storage Virtualization

• Pools physical storage, appearing as one device managed centrally.

Network Virtualization

• Combines network resources where bandwidth can be dynamically assigned to servers.
• SAN (Storage Area Network) is an example.

Cloud Computing

• Cloud computing delivers services, infrastructure, and storage over the internet, on-demand.
• Aspects of computing (Hardware, Networks, Storage, Services, and Interfaces) combine to deliver services.
• Cloud services can be provided as separate components or a complete platform.

Cloud Computing Implementation

• Public cloud: Services on the internet with limited control over the technology infrastructure (e.g. services from Amazon, Google, Microsoft).
• Private cloud: Services provided via an organization's intranet or hosted data center (e.g. used by medical offices and banking institutions).
• Hybrid cloud: Combines public and private cloud capabilities to address specific needs, e.g. using private for sensitive data and public for customer facing websites.

Public vs Private Cloud Computing

• Public clouds share virtualized resources supporting multiple customers. It uses internet connectivity suited for less sensitive data.
• Private clouds use a closed cluster of dedicated resources and support better security with connectivity via fiber and private networks, better suited for sensitive data.

Cloud Computing Advantages

• Scalability (cloud scale up or down based on demand)
• Straightforward cloud resource procurement.
• Standardised APIs mean seamless program interaction, enabling easier cloud service integration.
• Pay-as-you-go billing model for resource usage.

Cloud Computing Advantages (detailed)

• Enables document control, environment friendliness, rapid development, infinite storage, better security and more flexibility.
• Rapid development, infinite storage and improved work flow streamlining are benefits..

Cloud Computing Challenges

• Catastrophic failures are a concern.
• Reliability, availability, security, and interoperability are concerns for organizations using cloud-based services.