#Distributed System Architecture

Summary

This video explores the key concepts of distributed system architectures. It covers the definition of distributed systems, their components, and connectors. The video explains various architectures such as layered architecture, multi-tier architecture, and structured decentralized peer-to-peer architecture. Each architecture's characteristics, advantages, and applications are discussed, including scalability, fault tolerance, and efficient data management. The video also introduces the Chord algorithm, a peer-to-peer distributed hash table for decentralized data storage and retrieval, explaining how nodes communicate and store data within these systems.

Takeaways

• 💻 A distributed system is a network of independent computers working together as a single system to solve complex problems, store large amounts of data, and ensure high availability.
• 🧩 Components in a distributed system are modular units with defined interfaces, while connectors are communication links facilitating cooperation between components.
• 🏛️ Layered architecture allows for sequential communication between layers, where requests flow from the top to the bottom, and responses return from the bottom to the top.
• 🖥️ Multi-tier architecture (or n-tier architecture) divides application functionality into layers such as presentation, application logic, and data management, improving scalability and flexibility.
• 📊 In a multi-tier architecture, the presentation tier handles user interaction, the application tier processes business logic, and the data tier manages data storage and retrieval.
• 📈 Benefits of multi-tier architecture include scalability, maintainability, flexibility, load balancing, and support for distributed transactions using protocols like two-phase commit.
• 🔄 Structured decentralized peer-to-peer (P2P) architecture is decentralized and organized into a specific topology, promoting scalability, fault tolerance, and resource sharing among peers.
• 🔗 Distributed hash tables (DHT) in structured P2P architectures offer efficient data storage and retrieval by mapping data keys to nodes across a network.
• 🔐 Blockchain networks are an example of structured decentralized P2P architectures, offering secure transactions and decentralized data management.
• ⚙️ The Chord algorithm is a peer-to-peer distributed hash table technique used for decentralized data management, ensuring scalability, fault tolerance, and efficient data lookup through replication and finger tables.

Q & A

What is a distributed system?

A distributed system is a network of independent computers that work together as a single coherent system. The individual computers or nodes communicate and coordinate with each other to achieve a common goal. These systems can be used to solve complex problems, store large amounts of data, or provide services requiring high availability and reliability.

What are the components and connectors in a distributed system architecture?

In distributed system architecture, components are modular units with well-defined interfaces that are replaceable and reusable. Connectors are communication links between modules that mediate coordination or cooperation among components. Components can be deployed across different platforms and communicate over a network to achieve specific objectives.

What is a layered architecture in distributed systems?

Layered architecture separates components into layers, allowing modularity. Each interaction is sequential, where a layer contacts the adjacent layer. Requests flow from the top layer to the bottom layer, while responses move from the bottom to the top. This architecture is beneficial because layers can be replaced or modified independently, without affecting the entire system.

What are the main advantages of layered architecture?

The main advantages of layered architecture are its modularity, where each layer can be independently modified or replaced, and its predictability, as the requests and responses follow a predefined path between layers. This makes it easier to maintain and update the system.

What is multi-tier architecture, and how does it function?

Multi-tier architecture, also known as n-tier architecture, is a client-server architecture that separates application functionalities into distinct layers or tiers. It includes the presentation tier (user interface), the application tier (business logic), and the data tier (storage and management). The tiers interact with each other to process user requests and deliver the required data or services.

What are the key benefits of multi-tier architecture?

The benefits of multi-tier architecture include scalability (additional servers can be added to handle demand), maintainability (changes can be made to specific tiers without affecting the entire system), flexibility (tiers can be deployed on different platforms), load balancing (distributing requests among multiple instances), and transactional support (distributed transactions can be implemented).

What is structured decentralized peer-to-peer (P2P) architecture?

Structured decentralized peer-to-peer (P2P) architecture refers to a system where nodes (peers) are organized in a specific topology, such as rings or trees. There is no central authority, and peers communicate directly. The architecture is scalable, fault-tolerant, and improves resource utilization by sharing resources among peers.

What are the advantages of structured decentralized P2P architecture?

The advantages of structured decentralized P2P architecture include scalability, fault tolerance (the system remains operational even if some peers fail), and improved resource utilization as peers share resources, reducing the need for centralized infrastructure.

What is the purpose of a distributed hash table (DHT) in P2P networks?

A distributed hash table (DHT) in P2P networks is a data structure that stores key-value pairs across nodes. It allows efficient data storage and retrieval by mapping data keys to nodes in the network using a consistent hash function.

How does the Chord algorithm work in managing data in a decentralized system?

Chord is a peer-to-peer distributed hash table algorithm that assigns a unique identifier to each node and uses a consistent hash function to map data keys to nodes. Each node maintains a finger table with references to other nodes for efficient lookup and routing. Data is replicated across multiple nodes to ensure availability and fault tolerance.