◆ What is Endpoint?
A device located at the end of the PCI-Express I/O structure and has its own I/O capabilities (such as a graphics card). Commonly referred to as I/O devices or peripheral devices.
Among them, Legacy Endpoint is an Endpoint compatible with conventional PCI.
This Legacy Endpoint is used when only the interface part with the host is compatible with PCI-Express in existing PCI or PCI-X devices.
Legacy Endpoint allows I/O and locking transactions for compatibility with legacy PCI.

◆ What is Bridge Device?
A device that performs protocol conversion to connect PCI or PCI-X devices and cards to a PCI-Express system. It does not have any I/O capabilities of its own, so its functionality differs from that of the Legacy Endpoint.