Network device architecture for centralized packet processing

• US 20060023718A1
• Filed: 07/08/2004
• Published: 02/02/2006
• Est. Priority Date: 07/08/2004
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Joly, Christophe
• Granted Patent: US 7,808,983 B2
• Time in Patent Office: Days
• US Class Current: 370/392
• CPC Class Codes: H04L 45/245 Link aggregation, e.g. trunking
• CPC Class Codes: H04L 47/24 Traffic characterised by specific attributes, e.g. priority or QoS
• CPC Class Codes: H04L 47/32 by discarding or delaying data units, e.g. packets or frames
• CPC Class Codes: H04L 49/602 Multilayer or multiprotocol switching, e.g. IP switching
• CPC Class Codes: H04L 49/90 Buffering arrangements
• CPC Class Codes: H04L 49/901 using storage descriptor, e.g. read or write pointers
• CPC Class Codes: H04L 49/9031 Wraparound memory, e.g. overrun or underrun detection
• CPC Class Codes: Y02D 30/50 in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

A method and system for centralized packet processing is disclosed. The method includes transferring a packet received at a port interface of a network device to an uplink interface of the network device, and sending the packet to an uplink from the uplink interface. The transferring and the sending are performed irrespective of a destination of the packet.

Claims

1. An apparatus comprising:

a lower-layer network device comprising an upstream packet processing section, wherein

said upstream packet processing section comprises an uplink transmit unit,

said uplink transmit unit is configured to transfer a packet received by said lower-layer network device to an upper-layer network device coupled to said lower-layer network device, and

said upstream packet processing section is configured to perform said transferring irrespective of a destination of said packet.

2. The apparatus of claim 1, wherein

said upstream packet processing section is configured to send each packet received by said upstream packet processing section via said uplink transmit unit.

3. The apparatus of claim 1, wherein

said upstream packet processing section is configured to send a packet only to said uplink receive unit.

4. The apparatus of claim 1, wherein said lower-layer network device further comprises:

a downstream packet processing section comprising an uplink receive unit, wherein

said downstream packet processing section is configured to receive each packet received by said downstream packet processing section via said uplink receive unit.

5. The apparatus of claim 4, wherein

said downstream packet processing section is configured to receive said each packet only from said uplink receive unit.

6. The apparatus of claim 4, wherein said lower-layer network device further comprises:

a plurality of port interfaces, wherein

a receive interface of each of said port interfaces is coupled to said upstream packet processing section; and

a transmit interface of each of said port interfaces is coupled to said downstream packet processing section.

7. The apparatus of claim 6, wherein

said lower-layer network device is configured to prevent said packet from being transferred from a one of said receive interfaces to a one of said transmit interfaces without being sent via said uplink transmit unit and received via said uplink receive unit.

8. The apparatus of claim 6, wherein said lower-layer network device further comprises:

an interface controller unit, wherein

said interface controller unit is coupled to said upstream packet processing section and said downstream packet processing section.

9. The apparatus of claim 8, wherein said interface controller unit comprises:

local targeting logic.

10. The apparatus of claim 9, wherein

said local targeting logic is configured to generate a logical port index.

11. The apparatus of claim 6, further comprising:

an uplink, wherein

said uplink transmit unit and said uplink receive unit are coupled to said uplink,

said upstream packet processing section is further configured to send each packet received by said upstream packet processing section to said uplink via said uplink transmit unit, and

said downstream packet processing section is further configured to receive each packet received by said downstream packet processing section to said uplink via said uplink receive unit.

12. An apparatus comprising:

a lower-layer network device comprising an interface controller unit, wherein

said interface controller unit is configured to cause a packet received by said lower-layer network device to be transferred to an upper-layer network device coupled to said lower-layer network device, and

said interface controller unit is further configured to cause said transferring of said packet irrespective of a destination of said packet.

13. The apparatus of claim 12, wherein said lower-layer network device further comprises:

an uplink interface coupled to be controlled by said interface controller unit.

14. The apparatus of claim 13, wherein

said interface controller unit is configured to cause each packet received by said lower-layer network device to be sent to said uplink interface.

15. The apparatus of claim 14, wherein

said interface controller unit is configured to determine a source index and a destination index of said packet.

16. The apparatus of claim 15, wherein

said source index is a first logical port index, and

said destination index is a second logical port index.

17. The apparatus of claim 14, wherein said lower-layer network device further comprises:

a plurality of port interfaces, wherein

each of said port interfaces is coupled to said interface controller unit and to said uplink interface.

18. The apparatus of claim 17, wherein

said interface controller unit is configured to determine a source index of said packet based on a one of said port interfaces receiving said packet.

19. The apparatus of claim 17, wherein

said interface controller unit is configured to determine a destination index of said packet.

20. The apparatus of claim 17, wherein

said interface controller unit is further configured to cause each packet received by a one of said port interfaces to be sent to said uplink interface.

21. The apparatus of claim 20, wherein

said interface controller unit is further configured to cause each packet received by said uplink interface to be sent to at least one of said port interfaces.

22. The apparatus of claim 17, wherein said uplink interface further comprises:

an uplink transmit unit; and

an uplink receive unit, wherein

said packet is received by a one of said port interfaces, and

said interface controller unit is further configured to prevent said packet from being transferred to another of said port interfaces without first being sent via said uplink transmit unit and received via said uplink receive unit.

23. The apparatus of claim 17, wherein said lower-layer network device further comprises:

a packet processing unit, wherein

said packet processing unit is coupled between said each of said port interfaces and said uplink interface, and

said packet processing unit is coupled to said interface controller unit.

24. The apparatus of claim 23, wherein

said packet processing unit is configured to send said packet to an intended one of said port interfaces based on a destination index of said packet.

25. The apparatus of claim 13, wherein

said uplink interface is a high-speed interface unit.

26. The apparatus of claim 25, wherein said high-speed interface unit comprises:

a high-speed receive interface;

a high-speed transmit interface; and

a high-speed media access controller, wherein said high-speed media access controller is coupled to said high-speed receive interface and said high-speed transmit interface.

27. The apparatus of claim 26, wherein

said high-speed media access controller couples said high-speed receive interface and said high-speed transmit interface to an uplink.

28. The apparatus of claim 13, wherein said lower-layer network device further comprises:

a packet processing unit, coupled to said interface controller unit and said uplink interface.

29. The apparatus of claim 28, wherein said packet processing unit comprises:

a downstream queue controller; and

an upstream queue controller.

30. The apparatus of claim 29, wherein said packet processing unit further comprises:

a downstream drop decision unit, coupled to said downstream queue controller; and

an upstream drop decision unit, coupled to said upstream queue controller.

31. The apparatus of claim 29, wherein said packet processing unit further comprises:

a queue management module, coupled to said downstream queue controller and said upstream queue controller.

32. The apparatus of claim 29, wherein said packet processing unit further comprises:

a packet buffer; and

a packet buffer controller, coupled to said queue management module and said packet buffer.

33. The apparatus of claim 28, wherein said lower-layer network device further comprises:

a plurality of port interfaces, wherein each of said port interfaces is coupled to said interface controller unit and said packet processing unit.

34. The apparatus of claim 33, wherein

each of said port interfaces is a low-speed interface unit.

35. The apparatus of claim 34, wherein each of said low-speed interface units comprises:

a low-speed receive interface;

a low-speed transmit interface; and

a low-speed media access controller, wherein said low-speed media access controller is coupled to said low-speed receive interface and said low-speed transmit interface.

36. The apparatus of claim 12, wherein said interface controller unit further comprises:

local targeting logic.

37. The apparatus of claim 36, wherein said lower-layer network device further comprises:

a local targeting logic table, accessible by said local targeting logic.

38. The apparatus of claim 36, wherein said lower-layer network device further comprises:

an uplink interface, coupled to said interface controller unit.

39. The apparatus of claim 38, wherein said lower-layer network device further comprises:

a packet processing unit, coupled to said interface controller unit and said uplink interface; and

a plurality of port interfaces, wherein each of said port interfaces is coupled to said interface controller unit and said packet processing unit.

40. An apparatus comprising:

a network device configured to process a packet comprising a packet header, wherein

said packet header comprises

a source index field, and

a destination index field, and

said source index field and said destination index field are logical port indices.

41. The apparatus of claim 40, wherein said network device comprises:

an upstream packet processing section comprising an uplink transmit unit, wherein

said network device is a lower-layer network device,

said uplink transmit unit is configured to transfer said packet to an upper-layer network device coupled to said lower-layer network device, and

said upstream packet processing section is configured to perform said transferring irrespective of a destination index stored in said destination index field.

42. The apparatus of claim 40, wherein

said source index field contains a first logical port index, and

said destination index field contains a second logical port index.

43. The apparatus of claim 40, wherein said packet header further comprises:

a source flood enable field, and

a destination flood enable field.

44. The apparatus of claim 40, wherein said packet header further comprises:

a notify index learn field.

45. The apparatus of claim 44, wherein said packet header further comprises:

a capture function enable field.

46. The apparatus of claim 45, wherein said packet header further comprises:

a receive span field.

47. The apparatus of claim 45, wherein said packet header further comprises:

a bundle hash field.

48. A method comprising:

transferring a packet received at a port interface of a network device to an uplink interface of said network device; and

sending said packet to an uplink from said uplink interface, wherein

said transferring and said sending are performed irrespective of a destination of said packet.

49. The method of claim 48, further comprising:

transferring each packet received at said port interface to said uplink interface.

50. The method of claim 48, further comprising:

encapsulating said packet by adding an uplink encapsulation header to said packet, prior to sending said packet on said uplink.

51. The method of claim 50, wherein said uplink encapsulation header comprises:

a source index, wherein

said source index is a logical port index of said port interface.

52. The method of claim 51, wherein said uplink encapsulation header further comprises:

a destination index, wherein

said destination index is a logical port index of a port interface to which said packet is to be sent.

53. The method of claim 48, further comprising:

transferring a packet received at said uplink interface to one of a plurality of port interfaces of said network device, wherein

said port interfaces comprise said port interface.

54. The method of claim 53, further comprising:

identifying said one of said port interfaces using a destination index in a header of said packet received at said uplink interface, wherein

said destination index is a logical port index of a port interface to which said packet received at said uplink interface is to be sent.

55. The method of claim 48, wherein

said network device is a lower-layer network device.

56. The method of claim 55, further comprising:

receiving said packet from said uplink at an upper-layer network device.

57. The method of claim 56, further comprising:

encapsulating said packet by adding an uplink encapsulation header to said packet, prior to sending said packet via said uplink.

58. The method of claim 57, further comprising:

decapsulating said packet by removing said uplink encapsulation header from said packet, once said packet has been received at said upper-layer network device.

59. The method of claim 56, further comprising:

determining, at said upper-layer network device, processing to be performed with regard to said packet.

60. The method of claim 59, wherein said processing to be performed comprises:

causing said upper-layer network device to perform lower-layer protocol processing for said packet.

61. The method of claim 60, wherein said lower-layer protocol processing comprises:

causing said upper-layer network device to make a forwarding decision for said packet.

62. The method of claim 59, further comprising:

sending said packet from said upper-layer network device via said uplink.

63. The method of claim 62, further comprising:

receiving said packet from said uplink at said lower-layer network device; and

transferring said packet received from said uplink interface to a one of a plurality of port interfaces of said lower-layer network device, wherein

said port interfaces comprise said port interface.

64. The method of claim 63, wherein said sending said packet from said upper-layer network device comprises:

encapsulating said packet by adding an uplink encapsulation header to said packet, prior to sending said packet via said uplink.

65. The method of claim 64, wherein said receiving said packet from said uplink at said lower-layer network device comprises:

decapsulating said packet by removing said uplink encapsulation header from said packet.

66. A computer program product comprising:

a first set of instructions, executable on a computer system, configured to transfer a packet received at a port interface of a network device to an uplink interface of said network device irrespective of a destination of said packet;

a second set of instructions, executable on said computer system, configured to send said packet to an uplink from said uplink interface irrespective of said destination of said packet; and

computer readable media, wherein said computer program product is encoded in said computer readable media.

67. The computer program product of claim 66, further comprising:

a third set of instructions, executable on said computer system, configured to encapsulate said packet by adding an uplink encapsulation header to said packet, prior to sending said packet on said uplink.

68. The computer program product of claim 67, wherein said uplink encapsulation header comprises:

a source index, wherein

said source index is a logical port index of said port interface; and

a destination index, wherein

said destination index is a logical port index of a port interface to which said packet is to be sent.

69. The computer program product of claim 66, further comprising:

a third set of instructions, executable on said computer system, configured to transfer a packet received at said uplink interface to one of a plurality of port interfaces of said network device, wherein

said port interfaces comprise said port interface; and

a fourth set of instructions, executable on said computer system, configured to identify said one of said port interfaces using a destination index in a header of said packet received at said uplink interface, wherein

said destination index is a logical port index of a port interface to which said packet received at said uplink interface is to be sent.

70. The computer program product of claim 66, wherein said network device is a lower-layer network device, and further comprising:

a third set of instructions, executable on said computer system, configured to receive said packet from said uplink at an upper-layer network device.

71. The computer program product of claim 70, further comprising:

a fourth set of instructions, executable on said computer system, configured to determine, at said upper-layer network device, processing to be performed with regard to said packet.

72. The computer program product of claim 71, further comprising:

a fifth set of instructions, executable on said computer system, configured to perform said processing with regard to said packet.

73. The computer program product of claim 72, further comprising:

a sixth set of instructions, executable on said computer system, configured to cause said upper-layer network device to perform lower-layer protocol processing for said packet.

74. The computer program product of claim 73, further comprising:

a seventh set of instructions, executable on said computer system, configured to cause said upper-layer network device to make a forwarding decision for said packet.

75. The computer program product of claim 74, further comprising:

a eighth set of instructions, executable on said computer system, configured to send said packet from said upper-layer network device via said uplink;

a ninth set of instructions, executable on said computer system, configured to receive said packet from said uplink at said lower-layer network device; and

an tenth set of instructions, executable on said computer system, configured to transfer said packet received from said uplink interface to a one of a plurality of port interfaces of said lower-layer network device, wherein

said port interfaces comprise said port interface.

76. An network device comprising:

a port interface;

an uplink interface, coupled to an uplink;

means for transferring a packet received at said port interface to said uplink interface, wherein

said means for transferring is coupled to said port interface and to said uplink interface, and

said means for transferring is configured to transfer said packet to said uplink interface irrespective of a destination of said packet; and

means for sending said packet to an uplink via said uplink interface, wherein

said means for sending comprises said uplink interface,

said means for sending is coupled to said means for transferring, and

said means for sending is configured to send said packet to said uplink irrespective of said destination of said packet.

77. The network device of claim 76, further comprising:

means for encapsulating said packet comprising means for adding an uplink encapsulation header to said packet, wherein

said means for transferring comprises said means for encapsulating.

78. The network device of claim 77, wherein said uplink encapsulation header comprises:

a source index, wherein

said source index is a logical port index of said port interface; and

a destination index, wherein

said destination index is a logical port index of a port interface to which said packet is to be sent.

80. The network device of claim 76, wherein said network device is a lower-layer network device, and further comprising:

means for receiving said packet from said uplink at an upper-layer network device.

81. The network device of claim 80, further comprising:

means for determining, at said upper-layer network device, processing to be performed with regard to said packet.

82. The network device of claim 81, further comprising:

means for processing said packet comprising means for performing lower-layer protocol processing for said packet.

83. The network device of claim 82, further comprising:

means for performing lower-layer protocol processing comprising means for making a forwarding decision for said packet.

84. The network device of claim 83, further comprising:

a plurality of port interfaces;

means for sending said packet from said upper-layer network device via said uplink;

means for receiving said packet from said uplink at said lower-layer network device; and

means for transferring said packet received from said uplink interface to a one of said port interfaces, wherein

said means for transferring is coupled to said port interfaces, and

said port interfaces comprise said port interface.

79. The network device of claim D1, further comprising:

a plurality of port interfaces;

means for transferring a packet received at said uplink interface to one of said port interfaces, wherein

said port interfaces comprise said port interface; and

means for identifying said one of said port interfaces using a destination index in a header of said packet received at said uplink interface, wherein

said destination index is a logical port index of a destination port interface, and

said destination port interface is a port interface of said port interfaces to which said packet received at said uplink interface is to be sent.