Origin shield adds a caching layer between edge and origin:
Without shield:
- Each edge server fetches from origin on cache miss
- edge servers = potentially origin requests for same content
With shield:
- Edge servers fetch from shield server
- Shield fetches from origin once
- Origin sees one request instead of
Benefits:
- Dramatically reduces origin load
- Faster cache population
- Lower origin bandwidth costs
Trade-off: Adds one more hop for cache misses. Worth it for popular content.