Methods for supporting queries for CDN content

Available methods  

In general, a GRM DNS server can be deployed to receive DNS queries for

• The entire namespace for a content provider. In this case, the GRM DNS server takes over the DNS services for a content provider.
• Only specific domains within the CDN namespace. In this case, URL rewriting is used.

You need to negotiate with each content provider for which you provide CDN services to determine the method the content provider wants to use to redirect requests for CDN content. Some content providers might prefer to have the GRM DNS server handle all queries for an entire domain. Other content providers might prefer to use URL rewriting to selectively redirect requests to CDN content.

For example, a content provider just beginning service with a CDN hoster might want to rewrite only one URL initially to test the quality of service provided before committing to full service. Some content providers might be reluctant to expose their DNS configuration information to an outside organization.

Note
You must also set up host-name rewriting to handle cache misses for CDN content that is not cached in a GRM agent cache and, therefore, must be fetched from a CDN origin server. See Planning for handling cache misses for CDN content for more information.

Relationship between GRM domain list entries and the content handled  

The entries in the GRM domain list reflect the content handled by the CDN, as shown in the following table.

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File: grmdns4.htm
Last updated: 11/12/02 17:45:14