1. A controller for a life support device for a patient, comprising:
an actuator for life support operation;
a sensor for providing a sensor signal in response to life support operation;
a control section providing sequence control of the life support device, including generating a control state for the actuator in response to the sensor signal;
a first interface directly connected to the control section, wherein a failure of the control section results in failure of the first interface; and
a second interface connected to the first interface and to the actuator, wherein an output state of the second interface is set in response to a predetermined valid data sequence output from the control section to the second interface via the first interface, and wherein the set output state is maintained until the second interface means receives another predetermined valid data sequence so that the set output state is unaffected by the failure of the control section.
2. The controller for the life support device according to claim 1,
wherein the life support device is an extracorporeal circulation device, and
wherein the actuator is a motor for circulating blood.
3. The controller for the life support device according to claim 2, further comprising a clamp for stopping circulation of the blood in response to detection of air bubbles in an extracorporeal circulation path,
wherein the clamp is connected to the second interface for being controlled by the control section by corresponding predetermined data sequences output from the control section to the second interface via the first interface.
4. The controller for the life support device according to claim 14, further comprising:
a detector detecting a stop or runaway of the control section; and
an indicator providing a notification when the detector detects a stop or runaway of the control section;
wherein the control section and first interface are reset in response to the notification, and wherein the second interface is unaffected by the notification.
5. (canceled)
6. A method for controlling a life support device having an actuator, a sensor, a control section generating a control state for the actuator in response to the sensor, and a first interface directly connected to the control section, wherein a failure of the control section results in failure of the first interface, the method comprising the steps of:
connecting a second interface between the first interface and the actuator, wherein the second interface is unaffected by the failure of the control section;
the control section determining a control state for the actuator;
the control section sending a predetermined data sequence corresponding to the control state from the first interface to the second interface;
the second interface checking a validity of a received predetermined data sequence and modifying an output state of the second interface if the received predetermined data sequence is valid, otherwise leaving the output state unmodified, so that a last valid output state is maintained in the event of a failure of the control section.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A switch, comprising:
layer-2 processing circuitry configured to determine that:
outer and inner destination media access control (MAC) addresses of a packet correspond to a MAC address assigned to the switch, wherein the packet is encapsulated with an inner Ethernet header, a routable header, and an outer Ethernet header;
encapsulation circuitry configured to determine that:
a destination switch identifier of the routable header corresponds to a switch identifier assigned to the switch, wherein the routable header is placed between the outer and inner Ethernet headers;
Internet Protocol (IP) processing circuitry configured to lookup a destination IP address of a layer-3 header of the packet in a local layer-3 forwarding table in the switch, wherein the layer-3 header is distinct from the routable header, and wherein the destination IP address is a virtual IP address assigned to a virtual IP router, which is formed based on the switch in conjunction with at least another physical switch to operate as a single router; and
forwarding circuitry configured to determine an output port and construct a new header for the packet based on looking up the destination IP address in the local layer-3 forwarding table.
2. The switch of claim 1, wherein the layer-2 processing circuitry is further configured to determine a first virtual local area network (VLAN) tag in the inner Ethernet header; and
wherein the new header includes a new inner Ethernet header comprising a second VLAN tag.
3. The switch of claim 1, wherein the switch is a member of a network of interconnected switches, wherein the network of interconnected switches is controlled as a single logical switch.
4. The switch of claim 1, further comprising switching circuitry configured to switch the packet between VLANs based on the destination IP address.
5. The switch of claim 1, wherein the destination switch identifier is a virtual switch identifier; and
wherein the virtual IP router is associated with the virtual switch identifier.
6. The switch of claim 1, wherein the IP processing circuitry is further configured to map the virtual IP address to a virtual media access control (MAC) address.
7. The switch of claim 1, further comprising Address Resolution Protocol (ARP) circuitry configured to generate an ARP response for an IP address assigned to the switch, wherein the ARP response comprises a MAC address assigned to the switch.
8. A method, comprising:
determining that:
outer and inner destination media access control (MAC) addresses of a packet correspond to a MAC address assigned to a switch, wherein the packet is encapsulated with an inner Ethernet header, a routable header, and an outer Ethernet header; and
a destination switch identifier of the routable header corresponds to a switch identifier assigned to the switch, wherein the routable header is placed between the outer and inner Ethernet headers;
looking up a destination Internet Protocol (IP) address of a layer-3 header of the packet in a local layer-3 forwarding table in the switch, wherein the layer-3 header is distinct from the routable header, and wherein the destination IP address is a virtual IP address assigned to a virtual IP router, which is formed based on the switch in conjunction with at least another physical switch to operate as a single router; and
determining an output port and constructing a new header for the packet based on looking up the destination IP address in the local layer-3 forwarding table.
9. The method of claim 8, further comprising:
determining a first virtual local area network (VLAN) tag in the inner Ethernet header; and
including in the new header a new inner Ethernet header comprising a second VLAN tag.
10. The method of claim 8, wherein the switch is a member of a network of interconnected switches wherein the network of interconnected switches is controlled as a single logical switch.
11. The method of claim 8, further comprising switching the packet between VLANs based on the destination IP address.
12. The method of claim 8, wherein the destination switch identifier is a virtual switch identifier; and
wherein the virtual IP router is associated with the virtual switch identifier.
13. The method of claim 8, further comprising mapping the virtual IP address to a virtual media access control (MAC) address.
14. The method of claim 8, further comprising generating an Address Resolution Protocol (ARP) response for an IP address assigned to the switch, wherein the ARP response comprises a MAC address assigned to the switch.
15. A computing system, comprising:
a processor; and
a non-transitory computer-readable storage medium storing instructions which when executed by the processor causes the processor to perform a method, the method comprising:
determining that:
outer and inner destination media access control (MAC) addresses of a packet correspond to a MAC address assigned to the computing system, wherein the packet is encapsulated with an inner Ethernet header, a routable header, and an outer Ethernet header; and
a destination switch identifier of the routable header corresponds to a switch identifier is assigned to the computing system;
looking up a destination Internet Protocol (IP) address of a layer-3 header of the packet in a local layer-3 forwarding table in the computing system, wherein the layer-3 header is distinct from the routable header and wherein the destination IP address is a virtual IP address assigned to a virtual IP router, which is formed based on the switch in conjunction with at least another physical switch to operate as a single router; and
determining an output port and constructing a new header for the packet based on looking up the destination IP address in the local-layer-3 forwarding table.
16. The computing system of claim 15, within the method further comprises:
determining a first virtual local area network (VLAN) tag in the inner Ethernet header; and
including in the new header a new inner Ethernet header comprising a second VLAN tag.
17. The computing system of claim 15, wherein the computing system is a member of a network of interconnected switches, wherein the network of interconnected switches is controlled as a single logical switch.
18. The computing system of claim 15,
wherein the destination switch identifier is a virtual switch identifier; and
wherein the virtual IP router is associated with the virtual switch identifier.
19. The computing system of claim 15, wherein the method further comprises generating an Address Resolution Protocol (ARP) response for an IP address assigned to the computing system, wherein the ARP response comprises a MAC address assigned to the computing system.
20. The computing system of claim 15, whether the method further comprises switching the packet between VLANs based on the destination IP address.