Distributed System Engineering

Think Different - Dhiraj Patra
3 min readDec 30, 2023

Photo by Tima Miroshnichenko

I am going to comprehensive explanation of distributed systems engineering, key concepts, challenges, and examples:

Distributed Systems Engineering:

  • Concept: The field of designing and building systems that operate across multiple networked computers, working together as a unified entity.
  • Purpose: To achieve scalability, fault tolerance, and performance beyond the capabilities of a single machine.

Key Concepts:

  • Distributed Architectures:
  • Client-server: Clients request services from servers (e.g., web browsers and web servers).
  • Peer-to-peer: Participants share resources directly (e.g., file sharing networks).
  • Microservices: Decomposing applications into small, independent services (e.g., cloud-native applications).
  • Communication Protocols:
  • REST: Representational State Transfer, a common API architecture for web services.
  • RPC: Remote Procedure Calls, allowing processes to execute functions on remote machines.
  • Message Queues: Asynchronous communication for decoupling services (e.g., RabbitMQ, Kafka).
  • Data Consistency:
  • CAP Theorem: States that distributed systems can only guarantee two of three properties: consistency, availability, and partition tolerance.
  • Replication: Maintaining multiple copies of data for fault tolerance and performance.
  • Consensus Algorithms: Ensuring agreement among nodes in distributed systems (e.g., Paxos, Raft).
  • Fault Tolerance:
  • Redundancy: Redundant components for handling failures.
  • Circuit Breakers: Preventing cascading failures by isolating unhealthy components.

Examples of Distributed Systems:

  • Cloud Computing Platforms (AWS, Azure, GCP)
  • Large-scale Web Applications (Google, Facebook, Amazon)
  • Database Systems (Cassandra, MongoDB, Hadoop)
  • Content Delivery Networks (CDNs)
  • Blockchain Systems (Bitcoin, Ethereum)

Challenges in Distributed Systems Engineering:

  • Complexity: Managing multiple interconnected components and ensuring consistency.
  • Network Issues: Handling delays, failures, and security vulnerabilities.
  • Testing and Debugging: Difficult to replicate production environments for testing.

Skills and Tools:

  • Programming languages (Java, Python, Go, C++)
  • Distributed computing frameworks (Apache Hadoop, Apache Spark, Apache Kafka)
  • Cloud platforms (AWS, Azure, GCP)
  • Containerization technologies (Docker, Kubernetes)

Here’s a full architectural example of a product with a distributed system, using a large-scale e-commerce platform as a model:

Architecture Overview:

- Components:

  • Frontend Web Application: User-facing interface built with JavaScript frameworks (React, Angular, Vue).
  • Backend Microservices: Independent services for product catalog, shopping cart, checkout, order management, payment processing, user authentication, recommendations, etc.
  • API Gateway: Central point for routing requests to microservices.
  • Load Balancers: Distribute traffic across multiple instances for scalability and availability.
  • Databases: Multiple databases for different data types and workloads (MySQL, PostgreSQL, NoSQL options like Cassandra or MongoDB).
  • Message Queues: Asynchronous communication between services (RabbitMQ, Kafka).
  • Caches: Improve performance by storing frequently accessed data (Redis, Memcached).
  • Search Engines: Efficient product search (Elasticsearch, Solr).
  • Content Delivery Network (CDN): Global distribution of static content (images, videos, JavaScript files).

- Communication:

  • REST APIs: Primary communication protocol between services.
  • Message Queues: For asynchronous operations and event-driven architectures.

- Data Management:

  • Data Replication: Multiple database replicas for fault tolerance and performance.
  • Eventual Consistency: Acceptance of temporary inconsistencies for high availability.
  • Distributed Transactions: Coordination of updates across multiple services (two-phase commit, saga pattern).

- Scalability:

  • Horizontal Scaling: Adding more servers to handle increasing load.
  • Containerization: Packaging services into portable units for easy deployment and management (Docker, Kubernetes).

- Fault Tolerance:

  • Redundancy: Multiple instances of services and databases.
  • Circuit Breakers: Isolate unhealthy components to prevent cascading failures.
  • Health Checks and Monitoring: Proactive detection and response to issues.

- Security:

  • Authentication and Authorization: Control access to services and data.
  • Encryption: Protect sensitive data in transit and at rest.
  • Input Validation: Prevent injection attacks and data corruption.
  • Security Logging and Monitoring: Detect and respond to security threats.

- Deployment:

  • Cloud Infrastructure: Leverage cloud providers for global reach and elastic scaling (AWS, Azure, GCP).
  • Continuous Integration and Delivery (CI/CD): Automate testing and deployment processes.

eg.

This example demonstrates the complexity and interconnected nature of distributed systems, requiring careful consideration of scalability, fault tolerance, data consistency, and security.

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Think Different - Dhiraj Patra

I am a Software architect for AI, ML, IoT microservices cloud applications. Love to learn and share. https://dhirajpatra.github.io