Techniques for processing traffic transmitted over advanced switching compatible switch fabrics

• US 20060140226A1
• Filed: 12/28/2004
• Published: 06/29/2006
• Est. Priority Date: 12/28/2004
• Status: Abandoned Application

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Citterelle, Kevin, Ho, Michael, Adiletta, Matthew, Carrigan, Douglas, Qunell, Miriam, Kauschke, Michael, Kaempfer, Ernest, Fedders, Jeff, Garratt, Jason
• Application Number:
  US11/024,928
• Publication Number:
  US 20060140226A1
• Time in Patent Office: Days
• US Class Current: 370/539
• CPC Class Codes: H04J 3/0623 Synchronous multiplexing systems, e.g. synchronous digital hierarchy/synchronous optical network (SDH/SONET), synchronisation with a pointer process
• CPC Class Codes: H04J 3/0632 Synchronisation of packets and cells, e.g. transmission of voice via a packet network, circuit emulation service [CES] queuing arrangements in packet switching elements H04L49/90; synchronising systems for the synchronous transmission of a pulse code modulated video signal with one or more other pulse code modulated signals H04N7/56
• CPC Class Codes: H04J 3/08 Intermediate station arrangements, e.g. for branching, for tapping-off
• CPC Class Codes: H04J 3/1611 Synchronous digital hierarchy [SDH] or SONET H04J3/1664 takes precedence for interactions with OTN
• CPC Class Codes: H04J 3/1617 carrying packets or ATM cells
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/365 Dynamic adaptation of the packet size
• CPC Class Codes: H04L 47/43 Assembling or disassembling of packets, e.g. segmentation and reassembly [SAR]
• CPC Class Codes: H04Q 2213/13174 Data transmission, file transfer
• CPC Class Codes: H04Q 2213/13178 Control signals
• CPC Class Codes: H04Q 2213/13216 Code signals, frame structure
• CPC Class Codes: H04Q 2213/13296 Packet switching, X.25, frame relay

Abstract

Techniques for processing traffic for transmission over an Advanced Switching compatible switch fabric.

Claims

1. A method comprising:

selectively segmenting at least one of data packets, data frames, or control information when a transmission size limit is exceeded;

indicating application of segmentation in the header of an Advanced Switching compliant packet that transmits segmented data packets, data frames, or control information; and

prioritizing transmission of Advanced Switching compliant packets based on contents of the Advanced Switching compliant packets.

2. The method of claim 1, wherein the prioritizing comprises:

prioritizing Advanced Switching compliant packets containing high order SONET tributaries over Advanced Switching compliant packet containing low order SONET tributaries; and

prioritizing Advanced Switching compliant packets containing low order SONET tributaries over Advanced Switching compliant packets containing contents other than high or low order SONET tributaries.

3. The method of claim 1, wherein the prioritizing comprises:

providing a first fixed time period to transmit Advanced Switching compliant packets containing high order SONET tributaries;

providing a second fixed time period to transmit Advanced Switching compliant packets containing low order SONET tributaries, wherein the first fixed time period is longer than the second fixed time period; and

providing a variable time period for transmission of Advanced Switching compliant packets including contents other than high or low order SONET tributaries.

4. An apparatus comprising:

logic circuitry to selectively segment at least one of data packets, data frames, or control information when a transmission size limit is exceeded;

logic circuitry to indicate application of segmentation in the header of each Advanced Switching compliant packet that transmits segmented data packets, data frames, or control information; and

a packet scheduler to prioritize transmission of Advanced Switching compliant packets based on contents of the Advanced Switching compliant packets.

5. The apparatus of claim 4, wherein the packet scheduler is to:

prioritize Advanced Switching compliant packets containing high order SONET tributaries over Advanced Switching compliant packet containing low order SONET tributaries; and

prioritize Advanced Switching compliant packets containing low order SONET tributaries over Advanced Switching compliant packets containing contents other than high or low order SONET tributaries.

6. The apparatus of claim 4, wherein the packet scheduler is to:

provide a first fixed time period to transmit Advanced Switching compliant packets containing high order SONET tributaries;

provide a second fixed time period to transmit Advanced Switching compliant packets containing low order SONET tributaries, wherein the first fixed time period is longer than the second fixed time period; and

provide a variable time period for transmission of Advanced Switching compliant packet including contents other than high or low order SONET tributaries.

7. A method comprising:

allocating multiple containers each capable of storing SONET payload;

allocating multiple complementary containers, wherein each of the multiple complementary containers is associated with one of the multiple containers;

storing contents of SONET traffic in each of the multiple containers based on payload markers and time slot identifiers of the SONET traffic;

at a periodic rate, transferring contents of the multiple containers to multiple complementary containers;

forming segments from contents of the multiple complementary containers; and

providing segments of the same type and destined for the same egress end-point into the same payload of an Advanced Switching compatible packet.

8. The method of claim 7, wherein each of the multiple containers stores bytes from a particular STS-1.

9. The method of claim 7, wherein each of the multiple containers stores bytes from a particular VT.

10. The method of claim 7, wherein the SONET traffic includes one of high or low order tributaries.

11. An apparatus comprising:

multiple containers each capable of storing SONET payload based on payload markers and time slot identifiers of SONET traffic;

multiple complementary containers, wherein each of the multiple complementary containers is associated with each of the multiple containers, wherein at a periodic rate, multiple containers transfer contents to multiple complementary containers; and

a scheduler to form segments from contents of the multiple complementary containers and provide segments of the same type and destined for the same egress end-point into the same payload of an Advanced Switching compatible packet.

12. The apparatus of claim 11, wherein the type consists of low or high order SONET tributaries.

13. The apparatus of claim 11, wherein each of the multiple containers stores bytes from a particular STS-1.

14. The apparatus of claim 11, wherein each of the multiple containers stores bytes from a particular VT.

15. A method comprising:

if utilization of a line is approximately at or below a threshold, providing a packet designated for multicast into unicast queues associated with each of the destinations of the multicast;

if utilization of the line is above a threshold, providing a packet designated for multicast into a queue associated with multicast transmissions; and

providing a crossbar capability having overspeed of N/2, wherein N is a maximum number of possible output ports to which a packet may be multicast from the cross bar.

16. The method of claim 15, further comprising

receiving at least one packet in an Advanced Switching compliant format at an input port to the cross bar.

17. The method of claim 15, further comprising

routing through the crossbar a packet to an output port.

18. The method of claim 15, wherein providing a packet designated for multicast into a queue associated with multicast transmissions comprises assigning destinations for the packet designated for multicast based on any destination to which the packet is not provided for by the unicast queues.

19. An apparatus comprising:

a cross bar having an overspeed of N/2, wherein N is a maximum number of possible output ports to which a packet may be multicast through the cross bar;

an input port capable of providing packets to the cross bar;

a plurality of output ports each capable of receiving packets from the cross bar;

at least one unicast queue associated with the input port and capable of storing at least one packet destined for each output port;

a multicast queue capable of storing packets designated for multicast transmission; and

routing logic, wherein

if utilization of the input port is approximately at or below a threshold, the routing logic stores a packet designated for multicast into each of the at least one unicast queues capable of storing packets destined for each of the destination output ports of the multicast, and

if utilization of the input port is above a threshold, the routing logic stores a packet designated for multicast into the multicast queue.

20. The apparatus of claim 19, wherein the input port is to receive at least one packet in an Advanced Switching compliant format.

21. The apparatus of claim 19, wherein the cross bar is to route each of the at least one packet to an output port.

22. The apparatus of claim 19, wherein if utilization of the input port is above a threshold, the routing logic stores a packet designated for multicast into the multicast queue based on any destination to which the packet is not provided for by any of the at least one unicast queue.

23. A system comprising:

an Advanced Switching (AS) format compliant switch fabric;

a first line card capable to receive AS format compliant packets from the switch fabric or to transmit AS format compliant packets to the switch fabric; and

a second line card, comprising;

logic circuitry to selectively segment at least one of data packets, data frames, or control information when a transmission size limit is exceeded,

logic circuitry to indicate application of segmentation in the header of the Advanced Switching compliant packet that transmits segmented data packets, data frames, or control information, and

a packet scheduler to prioritize transmission of Advanced Switching compliant packets based on contents of the Advanced Switching compliant packets.

24. The system of claim 23, wherein the first line card comprises a SONET add-drop multiplexer.

25. The system of claim 23, wherein the first line card comprises an Ethernet line input.

26. A system comprising:

an Advanced Switching (AS) format compliant switch fabric;

a first line card capable to receive AS format compliant packets from the switch fabric or to transmit AS format compliant packets to the switch fabric; and

a second line card, comprising;

multiple containers each capable of storing SONET payload based on payload markers and time slot identifiers of SONET traffic;

multiple complementary containers, wherein each of the multiple complementary containers is associated with one of the multiple containers, wherein at a periodic rate, multiple containers transfer contents to multiple complementary containers; and

a scheduler to form segments from contents of the multiple complementary containers and provide segments of the same type and destined for the same egress end-point into the same payload of an Advanced Switching compatible packet.

27. The system of claim 26, wherein the first line card comprises a SONET add-drop multiplexer.

28. The system of claim 26, wherein the first line card comprises an Ethernet line input.

29. A system comprising:

an Advanced Switching (AS) format compliant switch fabric comprising;

a cross bar having an overspeed of N/2, wherein N is a maximum number of possible output ports to which a packet may be multicast through the crossbar,

an input port capable of providing packets to the cross bar,

a plurality of output ports each capable of receiving packets from the cross bar,

at least one unicast queue associated with the input port and capable of storing at least one packet destined for each output port,

a multicast queue capable of storing packets designated for multicast transmission, and routing logic, wherein

if utilization of the input port is approximately at or below a threshold, the routing logic stores a packet designated for multicast into each of the at least one unicast queues capable of storing packets destined for each of the destination output ports of the multicast, and

if utilization of the input port is above a threshold, the routing logic stores a packet designated for multicast into the multicast queue;

a first line card capable to receive AS format compliant packets from the switch fabric or to transmit AS format compliant packets to the switch fabric; and

a second line card capable to receive AS format compliant packets from the switch fabric or to transmit AS format compliant packets to the switch fabric.

30. The system of claim 29, wherein the first line card comprises a SONET add-drop multiplexer.

31. The system of claim 29, wherein the first line card comprises an Ethernet line input.