Large frame path MTU discovery and communication for FCoE devices
View Patent ↗Embodiments of the invention relate to performing network communications according to an existing protocol by using frames that are larger than those usually allowed by the existing protocol. Thus, embodiments of the present invention provide for an extension of the existing protocol which allows for the use of larger frames. The larger frames may result from the use of larger payloads and their size may be defined in terms of the payload size. Embodiments provide for use of various negotiation and initialization mechanisms of the existing protocol with additional modifications to allow for the negotiation of the use of larger frames. These modifications may provide for end to end negotiation of a larger frame or payload size. Some embodiments ensure that the negotiations are performed in such a manner that devices that feature the improvements of the present invention can communicate with devices that do not feature these improvements.
1. A system comprising:
a Fibre Channel over Ethernet (FCoE) network comprising an FCoE fabric;
a first device connected to the FCoE network; and
a second device connected to the FCoE network,
wherein the first device, the second device and the FCoE fabric are configured to negotiate a frame size larger than allowed by existing FCoE standards, and the first and second devices are configured to communicate through the FCoE network using frames of the negotiated frame size.
2. The system of claim 1 , wherein negotiating a frame size larger than allowed by existing FCoE standards is defined by negotiating a payload size larger than allowed by existing FCoE standards.
3. The system of claim 1 , further including a legacy device and/or native FC device, wherein the legacy device and/or native FC device is incapable of handling frames of size larger than allowed by existing FCoE standards, the first device, the legacy device and/or native FC device and the FCoE fabric being configured to negotiate a frame size in accordance with the existing FCoE standards for communications between the first device and the legacy device and/or native FC device.
4. The system of claim 1 , wherein the first device, the second device and the FCoE fabric are configured to negotiate a frame size larger than allowed by existing FCoE standards while they perform connection initialization operations specified by the existing FCoE standards.
5. The system of claim 4 , wherein the connection initialization operations specified by the existing FCoE standards are one or more operations selected from a group consisting of FIP advertisement, FIP solicitation, fabric login (FLOGI) and port login (PLOGI), as well as FDISC and other NPIV (N_Port ID Virtualization) login operations.
6. A method for operating a networked system including at least a first and second device connected to a Fibre Channel over Ethernet (FCoE) network including an FCoE fabric the method comprising:
negotiating a frame size between the first device, the second device and the FCoE fabric, the negotiated frame size being larger than allowed by existing FCoE standards; and
communicating between the first and second devices through the FCoE network using frames of the negotiated frame size.
7. The method of claim 6 , wherein negotiating a frame size larger than allowed by existing FCoE standards is defined by negotiating a payload size larger than allowed by existing FCoE standards.
8. The method of claim 6 , wherein the network further includes a legacy device and/or native FC device incapable of handling frames of size larger than allowed by existing FCoE standards, the method further including
negotiating a second frame size for communication between the first device and the legacy device and/or native FC device by the first device, the second device and the FCoE fabric, the second frame size being in accordance with the existing FCoE standards;
communicating between the first device and the legacy device and/or native FC device through the FCoE network using the second frame size.
9. The method of claim 6 further including performing connection initialization operations specified by the existing FCoE standards by the first device, the second device and the FCoE fabric, said connection initialization operations taking place while the first device, the second device, and the FCoE fabric are negotiating a frame size larger than allowed by existing FCoE standards.
10. The method of claim 9 , wherein the connection initialization operations specified by the existing FCoE standards are one or more operations selected from a group consisting of FIP advertisement, FIP solicitation, fabric login (FLOGI) and port login (PLOGI), as well as FDISC and other NPIV (N_Port ID Virtualization) login operations.
11. The method of claim 10 , wherein the performance of connection initialization operations specified by the existing FCoE standards and the negotiation of the frame size larger than allowed by existing FCoE standards include sending one or more initialization frames specified by the existing FCoE standards as being part of the connection initialization operations, said frames including an additional field that is not specified by the existing FCoE standards, said additional field at least partially defining a suggested frame size that is larger than allowed by existing FCoE standards.
12. The method of claim 11 , wherein the one or more initialization frames include at least one of the group consisting of: an FIP frame, an FCoE frame including a PLOGI request and an FCoE frame including a PLOGI response.
13. The method of claim 11 , wherein the suggested frame size that is larger than allowed by existing FCoE standards is defined by defining a suggested payload size larger than allowed by existing FCoE standards.
14. The method of claim 13 , wherein the suggested payload size that is larger than allowed by existing FCoE standards is defined by the use of the additional field in conjunction with a conventional field that is part of the frame, the conventional field storing a payload size that is allowed by existing FCoE standards.
15. The method of claim 14 , wherein the suggested payload size that is larger than allowed by existing FCoE standards is defined in terms of a predefined mathematical formula based on the values held in the additional field and the conventional field.
16. The method of claim 15 , wherein the additional field is associated with a default value, the default value being a value usually placed in that field by conventional devices, the predefined mathematical formula being such that if the default value is stored in the additional field, the predefined formula results in a payload size that is equal to the payload size stored by the conventional field.
17. A method performed by a device connected to a Fibre Channel over Ethernet (FCoE) network including an FCoE fabric the method comprising:
negotiating a frame size with a second device and the FCoE fabric, the negotiated frame size being larger than allowed by existing FCoE standards; and
communicating with the second device through the FCoE network using frames of the negotiated frame size.
18. The method of claim 17 , wherein negotiating a frame size larger than allowed by existing FCoE standards is defined by negotiating a payload size larger than allowed by existing FCoE standards.
19. The method of claim 17 , wherein the network further includes a legacy device and/or native FC device incapable of handling frames of size larger than allowed by existing FCoE standards, the method further including
negotiating a second frame size with the legacy device and/or native FC device and the FCoE fabric for communication with the legacy device and/or native FC device, the second frame size being in accordance with the existing FCoE standards;
communicating with the legacy device and/or native FC device through the FCoE network using the second frame size.
20. The method of claim 17 further including performing connection initialization operations specified by the existing FCoE standards, said connection initialization operations taking place while negotiating a frame size larger than allowed by existing FCoE standards.
21. The method of claim 20 , wherein the connection initialization operations specified by the existing FCoE standards are one or more operations selected from a group consisting of FIP advertisement, FIP solicitation, fabric login (FLOGI) and port login (PLOGI), as well as FDISC and other NPIV (N_Port ID Virtualization) login operations.
22. The method of claim 21 , wherein the performance of connection initialization operations specified by the existing FCoE standards and the negotiation of the frame size larger than allowed by existing FCoE standards include sending one or more initialization frames specified by the FCoE standards as being part of the connection initialization operations, said frames including an additional field that is not specified by the existing FCoE standards, said additional field at least partially defining a suggested frame size that is larger than allowed by existing FCoE standards.
23. The method of claim 22 , wherein the one or more initialization frames include at least one of the group consisting of: an FIP frame, an FCoE frame including a PLOGI request and an FCoE frame including a PLOGI response.
24. The method of claim 22 , wherein the suggested frame size that is larger than allowed by existing FCoE standards is defined by defining a suggested payload size larger than allowed by existing FCoE standards.
25. The method of claim 24 , wherein the suggested payload size that is larger than allowed by existing FCoE standards is defined by the use of the additional field in conjunction with a conventional field, the conventional field that is part of the frame, the conventional field storing a payload size that is allowed by existing FCoE standards.
26. The method of claim 25 , wherein the suggested payload size that is larger than allowed by existing FCoE standards is defined in terms of a predefined mathematical formula based on the values held in the additional field and the conventional field.
27. The method of claim 26 , wherein the additional field is associated with a default value, the default value being a value usually placed in that field by conventional devices, the predefined mathematical formula being such that if the default value is stored in the additional field, the predefined formula results in a payload size that is equal to the payload size stored by the conventional field.
28. A device connected to a Fibre Channel over Ethernet (FCoE) network including an FCoE fabric the device including circuitry configured to:
negotiate a frame size with a second device and the FCoE fabric, the negotiated frame size being larger than allowed by existing FCoE standards; and
communicate with the second device through the FCoE network using frames of the negotiated frame size.
29. The device of claim 28 , wherein the circuitry includes application specific circuitry configured to perform the negotiating and communicating steps.
30. The device of claim 28 , wherein the device includes a generally programmable processor and a memory including a plurality of instructions, the instructions being executable at the processor and configured to cause the processor to perform the negotiating and communicating steps.
31. A device connected to a Fibre Channel over Ethernet (FCoE) network including an FCoE fabric and including:
a processor;
a memory connected to the processor and including a plurality of computer executable instructions that are executable at the processor; and
a networking interface connected to the processor and the FCoE network,
wherein the computer executable instructions are such that when executed at the processor they cause the processor to
negotiate a frame size with a second device and the FCoE fabric, the negotiated frame size being larger than allowed by existing FCoE standards, and
communicate with the second device through the FCoE network using frames of the negotiated frame size.
32. The device of claim 31 , wherein the device is a computer.
33. The device of claim 31 , wherein the device is a storage device.
34. The storage device of claim 33 , wherein the storage device is a RAID array.
35. A Fibre Channel over Ethernet (FCoE) network switch connected to an FCoE network and to a first and second devices through the FCoE network, the network switch being configured to:
negotiate a frame size with the first and second devices, the negotiated frame size being larger than allowed by existing FCoE standards; and
forward communications between the first and second devices, the communications including frames of the negotiated frame size.
36. A Fibre Channel over Ethernet (FCoE) network switch connected to an FCoE network and to a first and second devices through the FCoE network, the network switch including:
a processor;
a memory connected to the processor and including a plurality of computer executable instructions that are executable at the processor; and
a networking interface connected to the processor and the FCoE network,
wherein the computer executable instructions are such that when executed at the processor they cause the processor to
negotiate a frame size with the first and second devices, the negotiated frame size being larger than allowed by existing FCoE standards; and
forward communications between the first and second devices, the communications including frames of the negotiated frame size.
37. A non-transitory computer-readable medium comprising a plurality of instructions, the instructions being configured for execution at a device connected to a Fibre Channel over Ethernet (FCoE) network including an FCoE fabric, the instructions being further configured to cause the device to perform a method when executed at the device, the method comprising:
negotiating a frame size with a second device and the FCoE fabric, the negotiated frame size being larger than allowed by existing FCoE standards; and
communicating with the second device through the FCoE network using frames of the negotiated frame size.
38. A non-transitory computer-readable medium comprising a plurality of instructions, the instructions being configured for execution at a Fibre Channel over Ethernet (FCoE) network switch connected to an FCoE network and to a first and second devices through the FCoE network, the instructions being further configured to cause the network switch to perform the following as a result of execution of the instructions thereon:
negotiate a frame size with the first and second devices, the negotiated frame size being larger than allowed by existing FCoE standards; and
forward communications between the first and second devices, the communications including frames of the negotiated frame size.