Ethernet enhancements
This disclosure describes enhancements to Ethernet for use in higher performance applications like Storage, HPC, and Ethernet based fabric interconnects. This disclosure provides various mechanisms for lossless fabric enhancements with error-detection and retransmissions to improve link reliability, frame pre-emption to allow higher priority traffic over lower priority traffic, virtual channel support for deadlock avoidance by enhancing Class of service functionality defined in IEEE 802.1Q, a new header format for efficient forwarding/routing in the fabric interconnect and header CRC for reliable cut-through forwarding in the fabric interconnect. The enhancements described herein, when added to standard and/or proprietary Ethernet protocols, broadens the applicability of Ethernet to newer usage models and fabric interconnects that are currently served by alternate fabric technologies like Infiniband, Fibre Channel and/or other proprietary technologies, etc.
1. A network controller to communicate with a network node, said network controller comprising:
a transmitter circuit to transmit a first Ethernet frame to said network node;
a frame preemption circuitry to interrupt transmission of said first Ethernet frame to transmit a second Ethernet frame, wherein said second Ethernet frame has a higher priority than said first Ethernet frame, wherein based on interruption of transmission of said first Ethernet frame, a transmitted portion of the first Ethernet frame includes an indicator at an end of the transmitted portion of the first Ethernet frame of whether the transmitted portion of the first Ethernet frame is a last fragment or only fragment of the first Ethernet frame; and
said frame preemption circuitry further to re-start transmission of a remaining fragment of said first Ethernet frame.
2. The network controller of claim 1 , wherein said remaining fragment comprises an offset field to indicate a start of said remaining fragment relative to a previous frame fragment.
3. The network controller of claim 2 , wherein said first Ethernet frame further comprises a fragment tag field to indicate an error status associated with said first Ethernet frame, wherein said offset field and said fragment tag field are provided to a receiver of said network node for reassembly of said first Ethernet frame.
4. The network controller of claim 1 , wherein said priority of said first and second Ethernet frames are based on a Quality of Service (QoS) field, a traffic class field, a virtual channel field or a priority field in each of said first and second Ethernet frames.
5. The network controller of claim 1 , wherein the first and second Ethernet frames are transmitted as part of a high performance computing (HPC) environment.
6. The network controller of claim 1 , wherein the network controller is to operate in a manner consistent with IEEE 802.1Q.
7. A method for enhanced Ethernet communication comprising:
transmitting a first Ethernet frame to a network node;
interrupting transmission of said first Ethernet frame to transmit a second Ethernet frame, wherein said second Ethernet frame has a higher priority than said first Ethernet frame;
including, in a transmitted portion of the first Ethernet frame, an indicator at an end of the transmitted portion of the first Ethernet frame of whether the transmitted portion of the first Ethernet frame is a last fragment or only fragment of the first Ethernet frame; and
re-starting transmission of a remaining fragment of said first Ethernet frame.
8. The method of claim 7 , further comprising including an offset field in said remaining fragment to indicate a start of said remaining fragment relative to a previous frame fragment.
9. The method of claim 8 , wherein said first Ethernet frame further comprises a fragment tag field to indicate an error status associated with said first Ethernet frame.
10. The method of claim 9 , further comprising, at a receiver, reassembling said first Ethernet frame based on said offset field and said fragment tag field.
11. The method of claim 7 , further comprising determining said priority of said first Ethernet and second Ethernet frames based on a Quality of Service (QoS) field, a traffic class field, a virtual channel field or a priority field in each of said first and second Ethernet frames.
12. At least one non-transitory computer-readable storage medium having instructions stored thereon which when executed by a processor result in the following operations for enhanced Ethernet communication, comprising:
transmitting a first Ethernet frame to a network node;
interrupting transmission of said first Ethernet frame to transmit a second Ethernet frame, wherein said second Ethernet frame has a higher priority than said first Ethernet frame;
including, in a transmitted portion of the first Ethernet frame, an indicator at an end of the transmitted portion of the first Ethernet frame of whether the transmitted portion of the first Ethernet frame is a last fragment or only fragment of the first Ethernet frame; and
re-starting transmission of a remaining fragment of said first Ethernet frame.
13. The computer-readable storage medium of claim 12 , further comprising: including an offset field in said remaining fragment to indicate a start of said remaining fragment relative to a previous frame fragment.
14. The computer-readable storage medium of claim 13 , wherein said first Ethernet frame further comprises a fragment tag field to indicate an error status associated with said first Ethernet frame.
15. The computer-readable storage medium of claim 14 , further comprising reassembling said first Ethernet frame based on said offset field and said fragment tag field.
16. The computer-readable storage medium of claim 12 , further comprising determining said priority of said first and second Ethernet frames based on a Quality of Service (QoS) field, a traffic class field, a virtual channel field or a priority field in each of said first and second Ethernet frames.