API Rate Limiting Gateway

Overview

The API Rate Limiting Gateway is a C++-based backend system designed to manage and control API traffic efficiently. It prevents excessive requests, protects backend services from overload, and ensures fair usage among multiple clients.

Key Features

API-Key Authentication for client identification and access control.
Multiple Rate-Limiting Algorithms:
- Token Bucket
- Fixed Window
- Sliding Window
Multithreaded Request Processing for handling concurrent API requests.
Thread Synchronization using mutexes to ensure safe access to shared resources.
Request Queuing for managing incoming traffic.
Configurable Request Limits for flexible client and endpoint management.
File-Based Logging for tracking requests and rate-limit events.
Statistics Tracking for monitoring API usage and gateway performance.

Technology Stack

Language: C++
Concepts: Multithreading, Mutex Synchronization, File Handling, Data Structures
Architecture: API Gateway / Request Management System

How It Works

Client requests first pass through the gateway, where the API key is validated and the applicable rate-limit policy is checked. The selected algorithm determines whether the request should be allowed or rejected. Multiple requests can be processed concurrently using threads while mutex synchronization maintains thread safety.

Algorithms Implemented

Token Bucket

Controls request bursts using a bucket of available tokens that are replenished over time.

Fixed Window

Limits the number of requests allowed within a predefined time interval.

Sliding Window

Provides more accurate traffic control by evaluating requests across a continuously moving time window.

Project Outcome

This project demonstrates practical implementation of C++, multithreading, synchronization, file handling, authentication, and backend system design. It provides a foundation for building reliable and scalable API infrastructure capable of handling concurrent traffic while maintaining controlled request flow.