Prior art

Analysis of Prior Art for U.S. Patent 7,593,428

This analysis details the prior art cited during the examination of U.S. Patent 7,593,428. Each reference is evaluated for its potential to anticipate the patent's claims under 35 U.S.C. § 102. The core innovation of patent 7,593,428 is the creation and processing of a single data packet containing multiple, distinct, and dynamically selectable portions, each protected by its own checksum, with the selection criteria being responsive to communication channel conditions.

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1. U.S. Patent 6,289,023 B1

• Full Citation: Hardware checksum assist for network protocol stacks, issued to Hewlett-Packard Company on September 11, 2001.
• Filing Date: September 25, 1997.
• Brief Description: This patent describes a hardware-based method to offload checksum calculations from the main CPU. It focuses on efficiently calculating a single checksum for a data packet by processing data "on the fly" as it moves between memory and a network interface controller.
• Potential Anticipation: This reference does not anticipate the claims of 7,593,428. Its primary concern is the efficiency of calculating a single checksum for a packet. It does not disclose or suggest using multiple checksums for different, selectable portions within a single packet, nor does it mention dynamically adjusting checksum strategies based on channel conditions.

2. U.S. Patent Application 2002/0184598 A1

• Full Citation: Providing a header checksum for packet data communications, published on December 5, 2002.
• Publication Date: December 5, 2002.
• Brief Description: This application details a method for calculating a checksum for the header of a data packet separately from the payload. This is a common practice in protocols like IP, where the header checksum protects header information, and a higher-layer protocol (like TCP/UDP) handles the payload checksum.
• Potential Anticipation: This reference is unlikely to anticipate the claims. While it involves two checksums in a broad sense (one for the header, one for the payload), it does not teach the novel concept of partitioning the payload or other parts of the packet into multiple, selectable portions, each with its own distinct checksum field in the header. The separation of header and payload checksums is standard and does not reflect the granular, dynamic, multi-part protection claimed in 7,593,428.

3. U.S. Patent 6,954,893 B2

• Full Citation: Method and apparatus for reliable unidirectional communication in a data network, issued to Lockheed Martin Corporation on October 11, 2005.
• Filing Date: August 15, 2000.
• Brief Description: This patent addresses reliable data transfer over unidirectional links (where no acknowledgments can be received). It proposes encapsulating data packets into a "super-packet" or frame that includes forward error correction (FEC) data. This FEC data allows the receiver to reconstruct lost packets.
• Potential Anticipation: This reference does not anticipate the key claims. Its focus is on reliability through FEC and packet bundling, which is a different mechanism from the multiple, distinct checksums within a single packet as claimed in 7,593,428. It does not disclose partitioning a packet into multiple checksum-protected regions.

4. U.S. Patent 7,161,960 B2

• Full Citation: Apparatus, and associated method, for forming, and operating upon, multiple-checksum-protected data packet, issued to Nokia Corporation on January 9, 2007.
• Filing Date: March 26, 2002.
• Brief Description: This patent is the direct parent of 7,593,428, which is a continuation of this application. It describes the same core invention: a method to create and process a data packet with multiple checksum-protected parts, where the protection scheme can be selected dynamically.
• Potential Anticipation: As the parent application, this patent does not act as prior art to invalidate 7,593,428 under 35 U.S.C. § 102. The '960 patent establishes the priority date for the shared invention. The claims of the '428 patent are presumably different in scope but rely on the same disclosure.

5. U.S. Patent 7,269,186 B2

• Full Citation: Protocol for framing a payload, issued to Qualcomm Incorporated on September 11, 2007.
• Filing Date: August 6, 2001.
• Brief Description: This patent discloses a framing protocol where a payload is segmented into one or more frames. Each frame includes a header and a portion of the payload. The header can contain information about the frame, such as its length and sequence number. The protocol is designed for radio link layers.
• Potential Anticipation: This reference does not appear to anticipate the claims. While it deals with segmenting a payload into frames, it does not teach that these frames are part of a single, cohesive data packet at the UDP layer that contains multiple checksum fields in its header for each of these distinct portions. The concept of dynamically selecting these portions based on channel conditions is also absent.

6. U.S. Patent 7,386,627 B1

• Full Citation: Methods and apparatus for precomputing checksums for streaming media, issued to Network Appliance, Inc. on June 10, 2008.
• Filing Date: January 29, 2002.
• Brief Description: This patent describes a system for improving the efficiency of streaming media. It involves pre-calculating checksums for data blocks before they are requested by a client and storing them. When a client requests a specific byte range, the system can quickly construct a packet and its corresponding checksum from the pre-calculated values.
• Potential Anticipation: This reference does not anticipate the claims of 7,593,428. Its innovation lies in the pre-computation and storage of checksums for efficiency, not in the structure of the packet itself. It does not disclose a packet format that contains multiple, selectable checksums for different portions of its own payload.

Conclusion:

The prior art cited by the examiner during the prosecution of U.S. Patent 7,593,428 does not appear to anticipate the independent claims. The references generally relate to checksum calculation efficiency, standard header/payload checksum separation, or framing protocols for reliability, but none disclose the core inventive concept: a single packet structure with multiple, selectable, checksum-protected portions, where the selection can be dynamically altered based on communication conditions. This novel combination of features allows the claims of 7,593,428 to be distinguished from the cited art.