Systems and method for the management and processing resource of requests by a service provider, such as a content delivery network (“CDN”) service provider, on behalf of a content provider are provided. The CDN service provider can measure the performance associated with the delivery of resources to requesting client computing devices from various computing devices associated with the CDN service provider. In one embodiment, the CDN service provider can utilize commands correspond to communication protocols that causes the requesting client computing device to transmit or receive protocol information from multiple computing devices associated with the CDN service provider's domain. Information associated with the processing of the protocol responses can be used to measure CDN service provider latencies.