Assessment of content delivery services using performance measurements from within an end user client application

Abstract

A system for measuring and monitoring performance of online content is provided. In one embodiment, the system includes an intermediary device, such as a web proxy, that receives client requests for content, such as requests for web pages. The device obtains the requested content, modifies it by applying one or more performance optimizations, and serves it to the client. The device also inserts code into the content for execution by the client to gather and report data reflecting, e.g., how quickly the client is able to get and process the content. The code includes information identifying the modifications the device made, and this is reported with the timing data, so that the effect on performance can be analyzed. In other embodiments, the device selects one of multiple versions of content, and the inserted code contains information identifying the selected version. The foregoing are merely examples; other embodiments are described herein.

What is claimed is: 
     
         1 .- 25 . (canceled) 
     
     
         26 . A proxy server in a content delivery network (CDN) for measuring the performance effect of modifications applied to given content as part of the delivery of the content to the client, the proxy server comprising:
 a network interface for receiving a request for a markup language file for a web page, the request being received from a client;   circuitry forming one or more processors and memory holding instructions to be executed by the one or more processors to cause the proxy server to respond to the request by:
 obtaining the markup language file from any of a source computer and a local cache that stores a copy of the markup language file previously obtained from the source computer; 
 applying a particular feature of the proxy server when processing the request, the particular feature corresponding to a product offered by the CDN to content provider customers; 
 in addition to said application of said particular feature, inserting code in the markup language file for execution by the client when processing the markup language file, wherein execution of the code will cause the client to gather timing information reflecting the client's processing of the markup language file in order to display the web page, and will cause the client to transmit the timing information in a beacon to any of the computer apparatus and another computer; 
 sending the markup language file with the inserted code to the client, in response to the request; 
 wherein said code includes an identifier that identifies the particular feature that the proxy server applied in when processing the request, the code specifying that the identifier will be transmitted with the timing information as a field in the beacon. 
   
     
     
         27 . The proxy server of  claim 26 , wherein the client comprises a web browser. 
     
     
         28 . The proxy server of  claim 26 , wherein the markup language file comprises an HTML file. 
     
     
         29 . The proxy server of  claim 26 , wherein the code is JavaScript code that is any of inlined into the markup language file and referenced by a URL inserted into the markup language file. 
     
     
         30 . The proxy server of  claim 26 , wherein the timing information includes information specified in the Navigation Timing or Resource Timing specification. 
     
     
         31 . The proxy server of  claim 26 , wherein the timing information includes one or more timestamps for a processing phase at the client. 
     
     
         32 . A method performed by a proxy server in a content delivery network (CDN) that comprises a network interface, circuitry forming one or more processors, and memory holding instructions for execution by the one or more processors to effect the method, the method comprising:
 receiving a request for a markup language file for a web page, the request being received from a client;   in response to the request, the proxy server:
 obtaining the markup language file from any of a source computer and a local cache that stores a copy of the markup language file previously obtained from the source computer; 
 applying a particular feature of the proxy server when processing the request, the particular feature corresponding to a product offered by the CDN to content provider customers; 
 in addition to said application of said particular feature, inserting code in the markup language file for execution by the client when processing the markup language file, wherein execution of the code will cause the client to gather timing information reflecting the client's processing of the markup language file in order to display the web page, and will cause the client to transmit the timing information in a beacon to any of the computer apparatus and another computer; 
 sending the markup language file with the inserted code to the client, in response to the request; 
 wherein said code includes an identifier that identifies the particular feature that the proxy server applied in when processing the request, the code specifying that the identifier will be transmitted with the timing information as a field in the beacon.