Multicast Group Partitioning Method Applicable to CDN in WDM Network

Multicast Group Partitioning Method Applicable to CDN in WDM Network

Content delivery network (CDN) is a mechanism to deliver multimedia content to end users on behalf of web content providers. Provider's content is distributed from content server to a set of delivery platforms located at Internet service providers (ISPS) through the CDN in order to realize better performance and availability than the system of centralized provider's servers. Multicasting the multimedia content usually requires broader bandwidth than unicasting service and accordingly WDM broadcast network has been highly recommended for the infrastructure network of CDN. Although the WDM broadcast network easily supports the multicast service, multicast partitioning problem must be resolved to reduce the receiver's waiting time and the number of transmission. In this paper, we propose methods for partitioning a multicast group into smaller subgroups and for scheduling a separate transmission for each of these subgroups. The proposed algorithms reduce the workload of content server and also decrease the receivers' waiting time by using the previous status of receivers.