Simple CDN Web Server

• Implements a simple cdn web server using a Primary Backup model, that can be used to host any kinds of files.

• The load_balancer acts as a geographic load balancer that redirects incoming requests to a proxy server

  • Redirects requests to a proxy server that is "close" to the requesting client/user
  • Should be an http server that redirects requests to a proxy
  • Must know locations (ports) of proxy servers

• The proxy server acts as a cache for the origin server.

  • If the proxy has stored the requested file then it serves the stored file
  • otherwise calls the to the origin server to serve the requested file
  • Should be an http server that either serves the file or maps the request to the grpc get method
  • Must know location (port) of origin server

• The origin server stores the original file

  • Returns the original file when requested by a proxy
  • Should be a grpc server

CDN Sequence Diagram

• The proxy and origin server share a proto file that defines the messages

• Extra Features

  • UI for uploading files to the origin server
  • Failure handling and fault tolerance for load_balancer and proxy servers

Setting up the CDN network

• The docker-compose.yml file specifies the configuration for each server. Each server is run in its own container that represents a machine/server rack its running in on the network
• The .env file specifies the ports for each server
• Add the ports and service definitions in the .env & docker-compose.yml file to add more servers

Running the network

1. Install Docker
2. Run docker compose up -d
3. Go to http://localhost:8000/test_file.html
4. Upload files to origin with python UI/UI.py
5. Stop servers with docker compose down --rmi all