TCP/IP offload device

• US 8,539,112 B2
• Filed: 05/16/2011
• Issued: 09/17/2013
• Est. Priority Date: 10/14/1997
• Status: Expired due to Fees

• Current Assignee: Alacritech, Inc.
• Original Assignee: Alacritech, Inc.
• Inventors: Craft, Peter K., Philbrick, Clive M., Boucher, Laurence B., Higgen, David A., Blightman, Stephen E. J., Starr, Daryl D.
• Primary Examiner(s): Sheikh, Ayaz
• Assistant Examiner(s): ASEFA, DEBEBE A
• Application Number:
  US13/108,729
• Publication Number:
  US 20110280243A1
• Time in Patent Office: 855 Days
• Field of Search: 370254-340, 709/250, 709/230
• US Class Current: 709/250
• CPC Class Codes: G06F 5/10 having a sequence of storage locations each being individually accessible for both enqueue and dequeue operations, e.g. using random access memory G06F5/065 takes precedence
• CPC Class Codes: H04L 49/901 using storage descriptor, e.g. read or write pointers
• CPC Class Codes: H04L 49/9042 Separate storage for different parts of the packet, e.g. header and payload
• CPC Class Codes: H04L 61/00 Network arrangements, protocols or services for addressing or naming
• CPC Class Codes: H04L 61/10 of different types
• CPC Class Codes: H04L 67/145 avoiding end of session, e.g. keep-alive, heartbeats, resumption message or wake-up for inactive or interrupted session
• CPC Class Codes: H04L 67/34 involving the movement of software or configuration parameters network booting or remote initial program loading [RIPL] G06F9/4416
• CPC Class Codes: H04L 67/62 Establishing a time schedule for servicing the requests
• CPC Class Codes: H04L 67/63 Routing a service request depending on the request content or context
• 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 69/162 involving adaptations of sockets based mechanisms secure socket layer H04L63/168
• CPC Class Codes: H04L 69/163 In-band adaptation of TCP data exchange; In-band control procedures
• CPC Class Codes: H04L 69/166 IP fragmentation; TCP segmentation
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers
• CPC Class Codes: H04L 69/327 in the session layer [OSI layer 5]
• CPC Class Codes: H04Q 2213/13093 Personal computer, PC
• CPC Class Codes: H04Q 2213/13103 Memory
• CPC Class Codes: H04Q 2213/13204 Protocols
• CPC Class Codes: H04Q 2213/13216 Code signals, frame structure
• CPC Class Codes: H04Q 2213/13299 Bus
• CPC Class Codes: H04Q 2213/1332 : Logic circuits
• CPC Class Codes: H04Q 2213/13345 : Intelligent networks, SCP
• CPC Class Codes: H04Q 3/0029 : Provisions for intelligent networking

Abstract

A host CPU runs a network protocol processing stack that provides instructions not only to process network messages but also to allocate processing of certain network messages to a specialized network communication device, offloading some of the most time consuming protocol processing from the host CPU to the network communication device. By allocating common and time consuming network processes to the device, while retaining the ability to handle less time intensive and more varied processing on the host stack, the network communication device can be relatively simple and cost effective. The host CPU, operating according to instructions from the stack, and the network communication device together determine whether and to what extent a given message is processed by the host CPU or by the network communication device.

Claims

1. A method comprising:

receiving, by a network interface that is coupled to a computer, a plurality of network packets that each contain data, an Internet Protocol (IP) header and a Transmission Control Protocol (TCP) header;

processing the IP and TCP headers of the packets by the network interface, including maintaining a TCP connection on the network interface corresponding to the packets and corresponding to an application running on the computer;

obtaining a destination for the data in a memory of the computer, such that information that is later stored in the destination will be controlled by the application;

providing an indication of the destination from the computer to the network interface; and

transferring the data to the destination, without transferring the IP headers or the TCP headers of the plurality of packets to the destination, and without processing the IP headers or the TCP headers by the computer.

2. The method of claim 1, wherein the network interface and the computer both perform TCP processing for the TCP connection.

3. The method of claim 1, wherein processing the IP and TCP headers of the packets by the network interface is performed by hardware fast-path processing.

4. The method of claim 1, wherein obtaining the destination for the data in the memory of the computer includes providing, by the network interface to the computer, a session layer header from one of the packets.

5. The method of claim 1, wherein obtaining the destination for the data in the memory of the computer includes analyzing a session layer header from one of the packets.

6. The method of claim 1, wherein the application is denoted by a port number in the TCP header of the packets.

7. The method of claim 1, wherein transferring the data to the destination is performed by direct memory access (DMA) of the network interface to a memory of the computer.

8. A method comprising:

receiving, by a network interface that is coupled to a computer, a plurality of packets that correspond to a Transmission Control Protocol (TCP) connection, each containing data, an Internet Protocol (IP) header and a TCP header, wherein the data is for a network file system application running on the computer;

processing the IP and TCP headers of the packets by the network interface, including maintaining the TCP connection on the network interface;

providing, by the network interface to the computer, a session layer header from one of the packets;

analyzing, by the computer, the session layer header, including obtaining a destination for the data in a memory of the computer, such that information that is later stored in the destination will be controlled by the application; and

transferring the data to the destination, without transferring the IP headers or the TCP headers of the plurality of packets to the destination, and without processing the IP headers or the TCP headers by the computer.

9. The method of claim 8, wherein the network interface and the computer both perform TCP processing for the TCP connection.

10. The method of claim 8, wherein processing the IP and TCP headers of the packets by the network interface is performed by hardware fast-path processing.

11. The method of claim 8, further comprising storing, by the network interface, the data from the packets without the IP headers or the TCP headers prior to transferring, by the network interface, the data to the destination.

12. The method of claim 8, wherein the application is denoted by a port number in the TCP header of the packets.

13. The method of claim 8, wherein transferring the data to the destination is performed by direct memory access (DMA) of the network interface to a memory of the computer.

14. A method comprising:

receiving, by a network interface that is coupled to a computer, a plurality of packets that correspond to a Transmission Control Protocol (TCP) connection, each containing data, an Internet Protocol (IP) header and a TCP header, wherein the data is for an application running on the computer;

processing the IP and TCP headers of the packets by the network interface, including maintaining the TCP connection on the network interface;

providing, by the network interface to the computer, a header portion of one of the packets;

analyzing, by the computer, the header portion, including obtaining a destination for the data in a memory of the computer, such that information that is later stored in the destination will be controlled by the application; and

transferring the data to the destination, without transferring the IP headers or the TCP headers of the plurality of packets to the destination, and without processing the IP headers or the TCP headers by the computer.

15. The method of claim 14, wherein the network interface and the computer both perform TCP processing for the TCP connection.

16. The method of claim 14, wherein processing the IP and TCP headers of the packets by the network interface is performed by hardware fast-path processing.

17. The method of claim 14, wherein the application is denoted by a port number in the transport layer header of the packets.

18. The method of claim 14, wherein transferring the data to the destination is performed by direct memory access (DMA) of the network interface to a memory of the computer.

19. The method of claim 14, wherein the header portion includes a session layer header.