Protocol stack that offloads a TCP connection from a host computer to a network interface device

• US 20050175003A1
• Filed: 01/11/2005
• Published: 08/11/2005
• Est. Priority Date: 10/14/1997
• Status: Active Grant

• Current Assignee: Alacritech, Inc.
• Original Assignee: Alacritech, Inc.
• Inventors: Higgen, David A., Philbrick, Clive M., Boucher, Laurence B., Craft, Peter K.
• Granted Patent: US 7,627,001 B2
• Time in Patent Office: Days
• US Class Current: 370/389
• CPC Class Codes: G02B 7/36 using image sharpness techniques , e.g. image processing techniques for generating autofocus signals image data processing per se G06T; in cameras having a solid state image sensor H04N23/67
• CPC Class Codes: H04L 49/90 Buffering arrangements
• CPC Class Codes: H04L 49/9042 Separate storage for different parts of the packet, e.g. header and payload
• CPC Class Codes: H04L 49/9063 Intermediate storage in different physical parts of a node or terminal
• 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 67/10 in which an application is distributed across nodes in the network software deployment G06F8/60; multiprogramming arrangements G06F9/46
• 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 69/08 Protocols for interworking; Protocol conversion
• CPC Class Codes: H04L 69/12 Protocol engines
• 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 69/163 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 69/32 Architecture of open systems interconnection [OSI] 7-layer type protocol stacks, e.g. the interfaces between the data link level and the physical level
• CPC Class Codes: H04L 9/40 Network security protocols

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 for processing network communications by a host having a stack of protocol processing layers and an intelligent network interface, the method comprising:

establishing, by the stack of protocol processing layers, a Transmission Control Protocol (TCP) connection, the TCP connection having a state and being identified at least in part by an Internet Protocol (IP) address and TCP port of the host, and an IP address and TCP port of a remote host; and

offloading, from the stack of protocol processing layers to the intelligent network interface, the state of the TCP connection and data transfer processing for the TCP connection.

2. The method of claim 1, further comprising receiving, by the intelligent network interface, a packet from a network, including updating the state of the TCP connection by the intelligent network interface.

3. The method of claim 1, further comprising transmitting, by the intelligent network interface, a packet to a network, including updating the state of the TCP connection by the intelligent network interface.

4. The method of claim 1, further comprising processing, by the intelligent network interface, a transport layer header of a packet corresponding to the TCP connection.

5. The method of claim 1, further comprising terminating, by the stack of protocol processing layers, the offloading.

6. The method of claim 1, further comprising processing, by the stack of protocol processing layers, a session layer header corresponding to the TCP connection.

7. The method of claim 1, wherein the intelligent network interface includes a network interface device and a device driver for the network interface device, and offloading the state of the TCP connection includes passing a data structure from the stack of protocol processing layers to the device driver.

8. A method for receiving network communications by a host having a stack of protocol processing layers and an intelligent network interface, the method comprising:

establishing, by the stack of protocol processing layers, a Transmission Control Protocol (TCP) connection, the TCP connection having a state and being identified at least in part by an Internet Protocol (IP) address and TCP port of the host, and an IP address and TCP port of a remote host; and

offloading, from the stack of protocol processing layers to the intelligent network interface, the state of the TCP connection.

9. The method of claim 8, wherein the offloading includes performing data transfer processing for the TCP connection by the intelligent network interface.

10. The method of claim 8, further comprising processing, by the stack of protocol processing layers, exceptions to error-free data transfer processing for the TCP connection.

11. The method of claim 8, further comprising processing, by the intelligent network interface, a packet received from a network, including updating the state of the TCP connection by the intelligent network interface.

12. The method of claim 8, further comprising transmitting, by the intelligent network interface, a packet to a network, including updating the state of the TCP connection by the intelligent network interface.

13. The method of claim 8, further comprising processing, by the intelligent network interface, a transport layer header of a packet corresponding to the TCP connection.

14. The method of claim 8, further comprising terminating, by the stack of protocol processing layers, the offloading.

15. The method of claim 8, further comprising processing, by the stack of protocol processing layers, a session layer header corresponding to the TCP connection, while the intelligent network interface maintains the TCP connection.

16. The method of claim 8, wherein the intelligent network interface includes a network interface device and a device driver for the network interface device, and offloading the state of the TCP connection includes passing a data structure from the stack of protocol processing layers to the device driver.

17. A method for processing network communications by a host having a stack of protocol processing layers and an intelligent network interface, the method comprising:

establishing, by the stack of protocol processing layers, a Transmission Control Protocol (TCP) connection, the TCP connection including a combination of information and being identified at least in part by an Internet Protocol (IP) address and TCP port of the host, and an IP address and TCP port of a remote host; and

offloading the TCP connection from the stack of protocol processing layers to the intelligent network interface, such that the intelligent network interface can modify a first portion of the information but cannot modify a second portion of the information.

18. The method of claim 17, wherein offloading the TCP connection includes communicating, from the stack of protocol processing layers to the intelligent network interface, a state of the TCP connection.

19. The method of claim 17, further comprising receiving, by the intelligent network interface, a packet from a network, including updating a state of the TCP connection by the intelligent network interface.

20. The method of claim 17, further comprising transmitting, by the intelligent network interface, a packet to a network, including updating a state of the TCP connection by the intelligent network interface.

21. The method of claim 17, further comprising processing, by the intelligent network interface, a transport layer header of a packet corresponding to the TCP connection, including updating a state of the TCP connection by the intelligent network interface.