Patent ID: 9747592
Date: 2017-08-29
CPC Classifications: G06F,G06Q,H04L

Claim:
1. A method for extending operation of a content delivery network (CDN) with a transparent caching server, the method comprising: inspecting, by the transparent caching server, (i) content passing over a digital network through the transparent caching server en route to a plurality of end users and (ii) end user requests passing from the plurality of end users over the digital network through the transparent caching server, the transparent caching server comprising a microprocessor and a memory storing cached copies of said content and a log; caching, by the transparent caching server, a first subset of said content to the memory according to a first caching policy, wherein the first subset of content omits a CDN key, the CDN key identifying content the CDN serves on behalf of a CDN customer; serving, by the transparent caching server, cached copies of the first subset of content from said memory to the plurality of end users over the digital network in response to a first subset of the end user requests; logging, by the transparent caching server, a first set of data network usage resulting from said serving the cached copies of the first subset of content, wherein logging the first set of data network usage comprises tracking the first set of data network usage without the CDN key as a first set of entries of the log; determining, by the transparent caching server, that the memory is full; based on the determination that the memory is full, caching, by the transparent caching server, a second subset of said content to the memory according to a different second caching policy with priority over the first caching policy, by replacing cached copies of the first subset of content in the memory with the second subset of content, the second subset of content comprising the CDN key; replacing, by the transparent caching server, a source Internet Protocol (IP) address in data packets containing cached copies of the second subset of content from a first IP address of the transparent caching server to a second IP address belonging to one CDN caching server of a set of CDN caching servers; serving, by the transparent caching server, said data packets containing the cached copies of the second subset of content to the plurality of end users over the digital network with the second IP address as the source IP address of the data packets; logging, by the transparent caching server, a second set of data network usage resulting from serving cached copies of the second subset of content with the first IP address of the transparent caching server instead of the second IP address used in said serving the caching copies of the second subset of content, wherein logging the second set of data network usage comprises tracking the second set of data network usage with the CDN key to a second set of entries of the log; and, providing, by the transparent caching server, said log comprising the first and second set of entries to the CDN.