CDN for VOD

Some features my CDN has implementing

1. Advanced cache management:

• Implement tiered caching strategies (memory, SSD, HDD)
• Implement cache eviction policies (LRU, LFU, FIFO)
• Add content-aware cache expiration policies based on video popularity

2. Video optimization:

• Adaptive bitrate streaming support (HLS, DASH)
• On-the-fly transcoding for different devices and network conditions
• Implement video thumbnail generation and caching

3. Security:

• Token-based authentication for video access
• DRM integration options
• Rate limiting to prevent abuse
• Implement IP whitelisting/blacklisting for access control
• Edge-level WAF capabilities
• Implement DDoS protection mechanisms

4. Performance enhancements:

• HTTP/3 and QUIC protocol support
• Implement Brotli or Zstandard compression for video files

5. Analytics and reporting:

• Real-time analytics dashboard for video performance
• Implement user engagement metrics (watch time, drop-off rates)
• Cache hit/miss ratio tracking
• Origin server health monitoring
• Real-time bandwidth usage metrics

6. CDN management:

• Multi-CDN support for failover and load balancing
• Automated deployment and scaling of CDN nodes

Cache tier

User          Edge Server         Redis            SSD Cache        Origin
 |                |                 |                  |                |
 |---Request----->|                 |                  |                |
 |                |--Lookup Key---->|                  |                |
 |                |<---Miss---------|                  |                |
 |                |----------------Lookup Key--------->|                |
 |                |<---------------Hit or Miss---------|                |
 |                |                 |                  |                |
 |                |  If SSD hit:    |                  |                |
 |                |--Update Counter>|                  |                |
 |                |                 |                  |                |
 |                |  If SSD & Redis miss:              |                |
 |                |---------------------------------------------Request>|
 |                |<--------------------------------------------Response|
 |                |                 |                  |                |
 |                |--Store Content->|  or  |--Store Content----------->|
 |                |                 |      |           |                |
 |<---Response----|                 |                  |                |

Architecture

+------------------+
                      |     CLIENTS      |
                      | (Web/Mobile/OTT) |
                      +--------+---------+
                               |
                               v
                      +------------------+
                      |  LOAD BALANCER   |
                      +--------+---------+
                               |
                               v
                      +------------------+
                      |   MANAGEMENT     |
                      | Request Routing  |
                      | Auto-scaling     |
                      | Multi-CDN        |
                      +--------+---------+
                               |
                               v
+-------------+      +-------------------+       +-------------+
|  ANALYTICS  |<---->|   EDGE LOCATIONS  |<----->|  SECURITY   |
| Real-time   |      |   (Global PoPs)   |       | Auth Tokens |
| Engagement  |      +--------+----------+       | DRM         |
| Bandwidth   |               |                  | Rate Limits |
| Cache Ratio |               |                  | WAF/DDoS    |
+-------------+               v                  +-------------+
                    +----------------------+
                    |     CACHE TIERS      |
                    |                      |
                    | Redis (Memory Cache) |
                    +----------+-----------+
                               |
                               v
                    +----------------------+
                    |   SSD Cache Tier     |
                    +----------+-----------+
                               |
                               v
                    +----------------------+
                    |   HDD Cache Tier     |
                    +----------+-----------+
                               |
               Cache Miss      v      Cache Hit
               +---------------+---------------+
               |                               |
               v                               |
    +----------------------+                   |
    |    ORIGIN SERVER     |                   |
    +----------+-----------+                   |
               |                               |
               v                               v
    +----------------------+        Back to Client
    |  VIDEO PROCESSING    |        through Edge
    | Transcoding          |
    | Thumbnail Generation |
    | Compression          |
    | Adaptive Bitrate     |
    +----------------------+