An Analytical View of Multiple CDNs Collaboration

Content Distribution Networks (CDN) are a well-known and accepted way to deliver content. Considering the ever growing number of users and also the growing number of small localized CDNs, there is a strong trend for collaboration among them. CDN collaboration may cause cost reduction for CDN providers and better quality of experience for the end user. However, CDN collaboration raises performance issues. This paper presents an analytical view of collaboration among CDNs. Our analytical approach provides studies of collaboration performance through metrics such as cache hit, latency, and number of caches. Then, we present a collaboration overhead representation, considering two collaboration request routing strategies. From our performance analyses, we show that CDN collaboration can reduce response time and could also help a primary CDN deal with a flash crowd event.