Media storage and CDN in HLD - Architecture Diagram

System Overview - Media storage and CDN

This system stores media files like images and videos and delivers them quickly to users worldwide. It uses a Content Delivery Network (CDN) to cache media close to users, reducing load times and server strain.

Architecture Diagram

CDN Edge Server

↓

Load Balancer

↓

Media Storage Service

↓

Object Storage

Components

User

client

Requests media content like images or videos

CDN Edge Server

cdn

Caches media content close to users to reduce latency and offload origin servers

Load Balancer

load_balancer

Distributes incoming media requests evenly across media storage service instances

Media Storage Service

service

Handles media requests, fetches media from object storage if not cached

Object Storage

storage

Stores original media files reliably and durably

Request Flow - 7 Hops

User → CDN Edge Server

CDN Edge Server → Cache (internal)

CDN Edge Server → Load Balancer

Load Balancer → Media Storage Service

Media Storage Service → Object Storage

Media Storage Service → CDN Edge Server

CDN Edge Server → User

Failure Scenario

Component Fails:CDN Edge Server

Impact:Users experience slower media delivery as requests bypass CDN cache and go directly to origin servers, increasing latency and load.

Mitigation:Traffic reroutes to other CDN edge servers or directly to load balancer; origin servers scale to handle increased load; CDN provider ensures multiple edge locations for redundancy.

Architecture Quiz - 3 Questions

Which component first checks if the media file is cached?

A Load Balancer

B Media Storage Service

C CDN Edge Server

D Object Storage

Design Principle

This design uses a CDN to cache media close to users, reducing latency and origin load. The load balancer distributes requests to scalable media service instances. Object storage holds original files reliably. Caching ensures fast repeated access, and failure handling ensures availability and performance.