Method and apparatus for blind checksum and correction for network transmissions

Abstract

Method and apparatus for providing a checksum in a network transmission. In one aspect of the invention, a checksum for a packet to be transmitted on a network is determined by retrieving packet information from a storage device, the packet information to be included in the packet to be transmitted. A blind checksum value is determined based on the retrieved packet information, and the blind checksum value is adjusted to a protocol checksum based on descriptor information describing the structure of the packet. The protocol checksum is inserted in the packet before the packet is transmitted.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] The present application is related to the following copending U.S. patent applications: [0002] U.S. patent application, Ser. No. ______ (Attorney Docket No. RPS920050059US1 / 3485P), entitled “Host Ethernet Adapter for Networking Offload in Server Environment”, filed on even date herewith and assigned to the assignee of the present invention. [0003] U.S. patent application, Ser. No. ______ (Attorney Docket No. RPS920050060US 1 / 3486P), entitled “Method and System for Accommodating Several Ethernet Ports and a Wrap Transmitted Flow Handled by a Simplified Frame-By-Frame Upper Structure”, filed on even date herewith and assigned to the assignee of the present invention. [0004] U.S. patent application, Ser. No. ______ (Attorney Docket No. RPS920050061US1 / 3487P), entitled “Method and Apparatus for Providing a Network Connection Table”, filed on even date herewith and assigned to the assignee of the present invention. [0005] U.S. patent applica...

AI Technical Summary

Benefits of technology

[0021] The present invention provides a method and apparatus that allows efficient checksum determination and transmission of packets having a checksum by determining a blind checksum, if necessary, and adjusting that blind checksum on-the-fly and without random accesses to data buffers. The invention allows low-latency checksum determination and packet transmission and flexibility in handling multiple packet information storage configurations.

Problems solved by technology

An additional concern is the risk that errors will be introduced in data from transmission over the network.

One problem with this packet transmission method is that it requires random access to the data buffers storing the packet, so that the checksum field can be accessed and written to with the determined checksum value.

This random access capability to a large output buffer adds expense to the system and is slow and sequential, adding latency to the system.

However, there are no existing methods to efficiently combine parts of a packet and handle the different packet storage configurations for checksum determination when transmitting.

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