1. A computer system for protecting one or more server computers by identifying a browser on a client computer comprising: one or more hardware processors; a memory coupled to the one or more hardware processors and storing one or more instructions, which when executed by the one or more hardware processors cause the one or more hardware processors to: supplement a set of web code with a set of instrumentation code, which when executed on the client computer collects a set of information that describes a document object model created by the client computer after the client computer executes the set of web code; send the set of web code and the set of instrumentation code to the client computer; receive the set of information from the client computer; identify the browser on the client computer based on the set of information that describes the document object model.