Method and system for handling out-of-order segments in a wireless system via direct data placement

• US 7,826,457 B2
• Filed: 05/11/2005
• Issued: 11/02/2010
• Est. Priority Date: 05/11/2004
• Status: Expired due to Fees

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: ElZur, Uri, Bennett, James D., Karaoguz, Jeyhan, Fischer, Matthew
• Primary Examiner(s): Kumar; Pankaj
• Assistant Examiner(s): Foud; Hicham B
• Application Number:
  US11/126,464
• Publication Number:
  US 20060007935A1
• Time in Patent Office: 2,001 Days
• Field of Search: 370/389, 370/394, 370/395.52, 370/412, 370/428, 370/429, 370/465, 370/473, 370/474
• US Class Current: 370/394
• CPC Class Codes: H04L 1/1841 Resequencing
• CPC Class Codes: H04L 12/2854 Wide area networks, e.g. public data networks
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/193 at the transport layer, e.g. TCP related
• CPC Class Codes: H04L 47/34 ensuring sequence integrity, e.g. using sequence numbers
• 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 49/9094 Arrangements for simultaneous transmit and receive, e.g. simultaneous reading/writing from/to the storage element
• CPC Class Codes: H04L 69/16 Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]
• CPC Class Codes: H04L 69/161 Implementation details of TCP/IP or UDP/IP stack architecture; Specification of modified or new header fields
• CPC Class Codes: H04L 69/166 IP fragmentation; TCP segmentation
• CPC Class Codes: H04W 28/10 Flow control between communication endpoints
• CPC Class Codes: H04W 28/14 using intermediate storage
• CPC Class Codes: H04W 8/04 Registration at HLR or HSS [Home Subscriber Server]
• CPC Class Codes: H04W 80/06 Transport layer protocols, e.g. TCP [Transport Control Protocol] over wireless transmission control protocol/Internet protocol [TCP/IP] or user datagram protocol [UDP] H04L69/16

Abstract

A method and system for handling or processing out-of-order TCP segments in a wireless system may comprise at least one of: placing a first TCP segment received by a wireless network processor in a host buffer and having a mapping between a TCP sequence number and a corresponding buffer address. It may be determined whether a second TCP segment received by the wireless network processor is one of an in-order TCP segment or an out-of-order TCP segment. If the second received TCP segment is an out-of-order TCP segment, then control information associated with at least the second TCP segment may be stored locally on the wireless network processor. The out-of-order TCP segment may be placed in a portion of the host buffer.

Claims

1. A method for handling out-of-order TCP segments in a wireless system, the method comprising:

parsing incoming TCP segments received by a wireless network processor into corresponding TCP header segments and/or corresponding TCP data segments;

storing said parsed incoming TCP segments in a host buffer, wherein said corresponding TCP header segments and/or said corresponding TCP data segments are stored in separate corresponding portions of said host buffer, wherein said host buffer is off-chip to said wireless network processor, and said host buffer is coupled to said wireless network processor via a host bus;

for said stored and parsed incoming TCP segments, determining whether a current received TCP segment is an in-order TCP segment or an out-of-order TCP segment with respect to an immediately previously received TCP segment; and

when said current received TCP segment is said out-of-order TCP segment;

storing control information associated with said out-of-order TCP segment locally on said wireless network processor; and

placing said out-of-order TCP segment in said corresponding portions of said host buffer based on said stored control information so that said out-of-order TCP segment is in order with respect to one or more previously received TCP segments.

2. The method according to claim 1, comprising recording at least a buffer address occupied by an end of said one or more previously received TCP segments on said wireless network processor, wherein said host buffer is one of a TCP buffer, ULP buffer and/or an application buffer.

3. The method according to claim 2, comprising, if said current received TCP segment is an in-order TCP segment, placing said in-order TCP segment adjacent to said immediately previously received TCP segments in said corresponding portions of said host buffer.

4. The method according to claim 3, comprising placing said in-order TCP segment starting from an address adjacent to said recorded buffer address occupied by said end of said one or more previously received TCP segments in said corresponding portions of said host buffer.

5. The method according to claim 1, comprising adjusting a TCP window to an end of a last in order received TCP segment upon said placing of said one or more previously received TCP segments in said corresponding portions of said host buffer.

6. The method according to claim 1, comprising mapping a TCP sequence number and a corresponding buffer address to said parsed incoming received TCP segments to said corresponding portions of said host buffer.

7. A system for handling out-of-order TCP segments, the system comprising:

at least one processor that performs parsing of incoming TCP segments received by a wireless network processor into corresponding TCP header segments and/or corresponding TCP data segments, said at least one processor stores said parsed incoming TCP segments in a host buffer, wherein said corresponding TCP header segments and/or said corresponding TCP data segments are stored in separate corresponding portions of said host buffer, wherein said host buffer is off-chip to said wireless network processor, and said host buffer is coupled to said wireless network processor via a host bus;

for said stored and parsed incoming TCP segments, said at least one processor determines from said parsed incoming TCP segments, one or more previously received TCP segments and a subsequent received TCP segment, whether a current received TCP segment is an in-order TCP segment or an out-of-order TCP segment with respect to an immediately previously received TCP segment; and

when said current received TCP segment is said out-of-order TCP segment;

said at least one processor stores control information associated with said out-of-order TCP segment locally on said wireless network processor; and

said at least one processor places said out-of-order TCP segment in said corresponding portions of said host buffer based on said stored control information so that said out-of-order TCP segment is in order with respect to one or more previously received TCP segments.

8. The system according to claim 7, wherein said at least one processor records at least a buffer address occupied by an end of said one or more previously received TCP segments on said wireless network processor, wherein said host buffer being one of a TCP buffer, ULP buffer and/or an application buffer.

9. The system according to claim 7, wherein said at least one processor places said in-order TCP segment adjacent to said immediately previously received TCP segment in said host buffer if said current received TCP segment is an in-order TCP segment.

10. The system according to claim 9, wherein said at least one processor places said in-order TCP segment starting from an address adjacent to said recorded address occupied by said end of said one or more previously received TCP segments in said corresponding portions of said host buffer.

11. The system according to claim 7, wherein said buffer address is provided by one or more of:

TCP, ULP, and a driver.

12. The system according to claim 7, wherein said at least one processor is one of a TCP offload engine (TOE), a RISC processor and a finite state machine (FSM), each of which is integrated within said wireless network processor.

13. The system according to claim 7, wherein said at least one processor maps a TCP sequence number and a corresponding buffer address to said parsed incoming received TCP segments to said corresponding portions of said host buffer.

14. A method for handling out-of-order TCP segments in a wireless system, the method comprising:

parsing incoming TCP segments received by a wireless network processor into corresponding TCP header segments and/or corresponding TCP data segments;

storing said parsed incoming TCP segments in a host buffer, wherein said corresponding TCP header segments and/or said corresponding TCP data segments are stored in separate corresponding portions of said host buffer;

for said stored incoming TCP segments, determining whether a current received TCP segment is an in-order TCP segment or an out-of-order TCP segment with respect to an immediately previously received TCP segment;

when said current received TCP segment is said out-of-order TCP segment;

storing control information associated with said out-of-order TCP segment locally on said wireless network processor;

placing said out-of-order TCP segment in said corresponding portions of said host buffer based on said stored control information so that said out-of-order TCP segment is in order with respect to one or more previously received TCP segments;

recording at least a buffer address occupied by an end of said one or more previously received TCP segments on said wireless network processor, wherein said host buffer is one of a TCP buffer, ULP buffer and/or an application buffer; and

when said current received TCP segment is said in-order TCP segment;

placing said in-order TCP segment adjacent to said immediately previously received TCP segments in said corresponding portions of said host buffer;

placing said in-order TCP segment starting from an address adjacent to said recorded buffer address occupied by said end of said one or more previously received TCP segments in said corresponding portions of said host buffer; and

one or both of;

recording by said wireless network processor, data indicating one or more of;

an end buffer address occupied by an end of said in-order TCP segment;

a start buffer address plus a length of a data portion of said in-order TCP segment; and

/or

a buffer address of a byte following an end of said in-order TCP segment; and

/or

storing on said wireless network processor, control information associated with said indicating data.

15. A method for handling out-of-order TCP segments in a wireless system, the method comprising:

parsing incoming TCP segments received by a wireless network processor into corresponding TCP header segments and/or corresponding TCP data segments;

storing said parsed incoming TCP segments in a host buffer, wherein said corresponding TCP header segments and/or said corresponding TCP data segments are stored in separate corresponding portions of said host buffer;

for said stored incoming TCP segments, determining whether a current received TCP segment is an in-order TCP segment or an out-of-order TCP segment with respect to an immediately previously received TCP segment; and

when said current received TCP segment is said out-of-order TCP segment;

storing control information associated with said out-of-order TCP segment locally on said wireless network processor;

placing said out-of-order TCP segment in said corresponding portions of said host buffer based on said stored control information so that said out-of-order TCP segment is in order with respect to one or more previously received TCP segments; and

one or both of;

recording on said wireless network processor, data indicating one or both of;

an address occupied by a start of said placed out-of-order TCP segment and an address occupied by an end of said placed out-of-order TCP segment; and

/or

a start buffer address of said placed out-of-order TCP segment plus a length occupied by said placed out-of-order TCP segment; and

/or

storing on said wireless network processor, control information associated with said indicating data on said wireless network processor.

16. The method according to claim 15, comprising receiving a new out-of-order TCP segment by said wireless network processor.

17. The method according to claim 16, comprising determining placement in said corresponding portions of said host buffer of said received new out-of-order TCP segment by said wireless network processor.

18. The method according to claim 16, comprising:

if said received new out-of-order TCP segment is in-order with said placed out-of-order TCP segment;

placing said received new out-of-order TCP segment adjacent to said placed out-of-order TCP segment in said corresponding portions of said host buffer; and

one or both of;

adjusting said start address occupied by said placed out-of-order TCP segment to become a start address of a combined said received new out-of-order TCP segment and said placed out-of-order TCP segment; and

/or

adjusting said end address occupied by said placed out-of-order TCP segment to become an end address of said combined said received new out-of-order TCP segment and said placed out-of-order TCP segment.

19. The method according to claim 16, comprising, if said received new out-of-order TCP segment is out-of-order with respect to said placed out-of-order TCP segment, placing said received new out-of-order TCP segment at an address in said corresponding portions of said host buffer that is one of located before said placed out-of-order TCP segment and located after said placed out-of-order TCP segment.

20. The method according to claim 19, comprising one or both of:

recording on said wireless network processor, location data representing one or more of;

a start address and an end address of a location where said received new TCP segment is placed in said corresponding portions of said host buffer on said wireless network processor;

a start address plus a length of where said received new TCP segment is placed in said corresponding portions of said host buffer on said wireless network processor; and

/or

a byte following an end of where said received new TCP segment is placed in said corresponding portions of said host buffer on said wireless network processor; and

storing on said wireless network processor, control information associated with at least said location data of where said received new TCP segment is placed.

21. A method for handling out-of-order TCP segments in a wireless system, the method comprising:

parsing incoming TCP segments received by a wireless network processor into corresponding TCP header segments and/or corresponding TCP data segments;

storing said parsed incoming TCP segments in a host buffer, wherein said corresponding TCP header segments and/or said corresponding TCP data segments are stored in separate corresponding portions of said host buffer;

for said stored incoming TCP segments, determining whether a current received TCP segment is an in-order TCP segment or an out-of-order TCP segment with respect to an immediately previously received TCP segment; and

when said current received TCP segment is said out-of-order TCP segment;

storing control information associated with said out-of-order TCP segment locally on said wireless network processor;

placing said out-of-order TCP segment in said corresponding portions of said host buffer based on said stored control information so that said out-of-order TCP segment is in order with respect to one or more previously received TCP segments;

adjusting a TCP window to an end of a last in order received TCP segment upon said placing of said one or more previously received TCP segments in said corresponding portions of said host buffer; and

one of;

adjusting a left edge of said TCP window to a next byte immediately following an end of an out-of-order TCP segment placed adjacent to an end of a last in-order previously received TCP segment; and

adjusting said left edge of said TCP window to a next byte immediately following an end of a last of a plurality of out-of-order TCP segments placed adjacent to an end of a last in-order previously received TCP segment.

22. A method for handling out-of-order TCP segments in a wireless system, the method comprising:

parsing incoming TCP segments received by a wireless network processor into corresponding TCP header segments and/or corresponding TCP data segments;

storing said parsed incoming TCP segments in a host buffer, wherein said corresponding TCP header segments and/or said corresponding TCP data segments are stored in separate corresponding portions of said host buffer;

for said stored incoming TCP segments, determining whether a current received TCP segment is an in-order TCP segment or an out-of-order TCP segment with respect to an immediately previously received TCP segment; and

when said current received TCP segment is said out-of-order TCP segment;

storing control information associated with said out-of-order TCP segment locally on said wireless network processor;

placing said out-of-order TCP segment in said corresponding portions of said host buffer based on said stored control information so that said out-of-order TCP segment is in order with respect to one or more previously received TCP segments;

adjusting a TCP window to an end of a last in order received TCP segment upon said placing of said one or more previously received TCP segments in said corresponding portions of said host buffer; and

adjusting a left edge of said TCP window to the next byte immediately following an end of a last in-order TCP segment placed adjacent to said first received TCP segment.

23. The method according to claim 22, comprising storing control information associated with at least a location of said TCP window on said wireless network processor.

24. The method according to claim 23, comprising updating said stored control information associated with at least a location of said TCP window whenever said TCP window is adjusted.

25. A method for handling out-of-order TCP segments in a wireless system, the method comprising:

parsing incoming TCP segments received by a wireless network processor into corresponding TCP header segments and/or corresponding TCP data segments;

storing said parsed incoming TCP segments in a host buffer, wherein said corresponding TCP header segments and/or said corresponding TCP data segments are stored in separate corresponding portions of said host buffer;

for said stored incoming TCP segments, determining whether a current received TCP segment is an in-order TCP segment or an out-of-order TCP segment with respect to an immediately previously received TCP segment; and

when said current received TCP segment is said out-of-order TCP segment;

storing control information associated with said out-of-order TCP segment locally on said wireless network processor;

placing said out-of-order TCP segment in said corresponding portions of said host buffer based on said stored control information so that said out-of-order TCP segment is in order with respect to one or more previously received TCP segments;

computing a buffer address in a first buffer for a location of a first byte of data for said one or more previously TCP segments;

computing a buffer address for a first byte of data in said current TCP segment based on a buffer address that corresponds to a TCP segment number of a second TCP segment; and

computing an offset from a TCP segment number that corresponds to a first TCP segment to a first byte of said current TCP segment.

26. The method according to claim 25, comprising determining whether said computed offset is larger than a length of said first buffer.

27. The method according to claim 26, comprising, if said computed offset is larger than said length of said first buffer, subtracting said length of said first buffer from said computed offset resulting in a new offset.

28. The method according to claim 27, comprising, subtracting a length of a second buffer from said new offset.

29. The method according to claim 28, comprising, if said subtracting of said second buffer results in said new offset being less than a length of said second buffer, buffering data for said current TCP segment in said first buffer and said second buffer.

30. The method according to claim 29, comprising, if said new offset is greater than a length of said second buffer, subtracting a length of other buffers until one of:

said buffers are exhausted; and

a remaining offset is less than a length of a current buffer.

31. The method according to claim 30, comprising, if a remaining offset is less than a length of said current buffer, buffering data for said current TCP segment in said second buffer, said third buffer, and said other buffers.

32. The method according to claim 30, comprising, if said buffers are exhausted, dropping said current TCP segment.

33. A system for handling out-of-order TCP segments in a wireless, the system comprising:

at least one processor that performs parsing incoming TCP segments received by a wireless network processor into corresponding TCP header segments and/or corresponding TCP data segments, said at least one processor stores said parsed incoming TCP segments in a host buffer, wherein said corresponding TCP header segments and/or said corresponding TCP data segments are stored in separate corresponding portions of said host buffer;

for said stored incoming TCP segments, said at least one processor determines from said parsed incoming TCP segments, one or more previously received TCP segments and a subsequent received TCP segment, whether a current received TCP segment is an in-order TCP segment or an out-of-order TCP segment with respect to an immediately previously received TCP segment; and

when said current received TCP segment is said out-of-order TCP segment;

said at least one processor stores control information associated with said out-of-order TCP segment locally on said wireless network processor;

said at least one processor places said out-of-order TCP segment in said corresponding portions of said host buffer based on said stored control information so that said out-of-order TCP segment is in order with respect to one or more previously received TCP segments;

wherein said at least one processor places said in-order TCP segment adjacent to said immediately previously received TCP segment in said host buffer, if said current received TCP segment is an in-order TCP segment;

wherein said at least one processor places said in-order TCP segment starting from an address adjacent to said recorded address occupied by said end of said one or more previously received TCP segments in said corresponding portions of said host buffer; and

wherein said at least one processor performs one or both of;

records by said wireless network processor, data indicating one or more of;

an end buffer address occupied by an end of said in-order TCP segment;

a start buffer address plus a length of a data portion of said in-order TCP segment; and

/or

a buffer address of a byte following an end of said in-order TCP segment; and

/or

stores on said wireless network processor, control information associated with said indicating data.

34. A system for handling out-of-order TCP segments in a wireless, the system comprising:

at least one processor that performs parsing incoming TCP segments received by a wireless network processor into corresponding TCP header segments and/or corresponding TCP data segments, said at least one processor stores said parsed incoming TCP segments in a host buffer, wherein said corresponding TCP header segments and/or said corresponding TCP data segments are stored in separate corresponding portions of said host buffer;

for said stored incoming TCP segments, said at least one processor determines from said parsed incoming TCP segments, one or more previously received TCP segments and a subsequent received TCP segment, whether a current received TCP segment is an in-order TCP segment or an out-of-order TCP segment with respect to an immediately previously received TCP segment; and

when said current received TCP segment is said out-of-order TCP segment;

said at least one processor stores control information associated with said out-of-order TCP segment locally on said wireless network processor;

said at least one processor places said out-of-order TCP segment in said corresponding portions of said host buffer based on said stored control information so that said out-of-order TCP segment is in order with respect to one or more previously received TCP segments;

wherein said at least one processor performs one or both of;

records on said wireless network processor, data indicating one or both of;

an address occupied by a start of said placed out-of-order TCP segment and an address occupied by an end of said placed out-of-order TCP segment; and

/or

a start buffer address of said placed out-of-order TCP segment plus a length occupied by said placed out-of-order TCP segment; and

/or stores on said wireless network processor, control information associated with said indicating data on said wireless network processor.