The present invention relates to a system for confirming a secure key exchange. BACKGROUND 1. FIELD The present invention relates generally to computer security and, more specifically, to establishing a shared encryption key between system components. 2. DESCRIPTION A computer system, such as a personal computer (PC), workstation, server, mainframe computer and so on, may comprise a number of different components. Some of the system components may be peripherals used by the system to communicate with a user or another system. For example, keyboards and mice are commonly used by the user to input data into the system. A display may be used to display information to the user. A network interface device may be used to connect the computer system to other computer systems or devices over a network. Some system components may be coupled to other components Using protocols known as "plug and play" protocols. For example, by using a Universal Serial Bus (USB), a system may allow multiple peripheral devices to be connected to the system. When a new peripheral is connected to the system, the system detects and identifies the newly added system component. Such a scheme typically relies on at least one host controller device