1. A content delivery network (CDN), the CDN serving resources on behalf of one or more customers of the CDN, the CDN comprising: (a) a control core; and (b) a plurality of cache servers, each particular cache server of said plurality of cache servers being constructed and adapted to: (b)(1) upon joining the CDN, (b)(1)(1) obtain global configuration data from the control core; and (b)(2) having joined the CDN, (b)(2)(1) obtain updated global configuration data, if needed; and (b)(2)(2) obtain customer configuration information associated with at least one customer of the CDN; (b)(2)(3) serve to a client a particular resource associated with a particular customer of the CDN in accordance with (i) the global configuration data, and (ii) customer configuration information obtained in (b)(2)(2) and associated with the particular customer.