| 摘要 |
<p>A node on a bus structure includes a physical interface to the bus structure. The physical interface determines the port on which an inbound bus packet is received and transmits an outbound bus packet only on an appropriate port connected to the destination node. When receiving a bus packet, the physical interface determines if the port on which the packet was received is a secure port. If it is determined that the packet was received on a secure port, the packet is then dumped to a direct memory access channel where the packet is processed as usual without requiring processor intervention. If the packet was received on an unsecure port, the packet is dumped to a general receive area and the processor is interrupted. The processor then examines the packet to determine whether the packet can be processed without affecting the security of the node. When transmitting a bus packet, the port to which the destination node of the bus packet is connected is determined. The bus packet is then only transmitted on this destination port while the other ports within the physical interface circuit are held busy.</p> |
