Matthew J Fischer

US Patent:

6640325, Oct 28, 2003

Filed:

May 22, 2000

Appl. No.:

09/577677

Inventors:

Matthew J. Fischer - Mountain View CA

Assignee:

Advanced Micro Devices, Inc. - Sunnyvale CA

International Classification:

G08C 2502

US Classification:

714748, 709232

Abstract:

A method and system for providing a low-level recovery of data on a communication network that provides an immediate negative acknowledgement of a data packet that contains bit errors, as determined by a receiving node on the network. The data packets contain two error detection mechanisms, with the first error detection mechanism being used by the receiving node to determine whether the data packet is uniquely addressed to that receiving node. When this is determined by the receiving node, the data payload is then checked to determine whether it contains a bit error. When an error is detected, the receiving node immediately sends out a negative acknowledgement, prior to the normal interframe spacing provided in network protocols, so that the transmitting node becomes aware that the data packet was not properly received at the receiving node. The transmitting node can then retransmit the data packet.

US Patent:

6747996, Jun 8, 2004

Filed:

Dec 7, 2000

Appl. No.:

09/732213

Inventors:

John T. Holloway - Atherton CA
Matthew James Fischer - Mountain View CA
Jason Alexander Trachewsky - Palo Alto CA

Assignee:

Broadcom Corporation - Irvine CA

International Classification:

H04J 306

US Classification:

370503, 370516

Abstract:

A method of providing for synchronizing one or more synchronous terminals with one or more synchronous endpoints, each synchronous terminal and each synchronous endpoint having an asynchronous communications network coupled between at least one synchronous terminal and at least one synchronous endpoint. A synchronization protocol is established between a synchronous terminal and a synchronous end point by providing a gateway between the asynchronous communications network and the synchronous end point, the gateway communicating with the synchronous terminal over the asynchronous communications network in accordance with the synchronization protocol. The synchronization protocol includes sending a message from the gateway to the synchronous terminal, the message containing a timestamp identifying a clock associated with the synchronous end point. The synchronous terminal establishes a clock associated with the synchronous terminal by creating a clock estimate based upon the timestamp message and access jitter expected from the asynchronous communications network such that the clock associated with the synchronous terminal enables packet sampling and transmission onto the asynchronous communications network to and from the synchronous terminal to be synchronized with the clock associated with the synchronous end point.

US Patent:

6807189, Oct 19, 2004

Filed:

Apr 7, 2000

Appl. No.:

09/545514

Inventors:

Matthew J. Fischer - Mountain View CA

Assignee:

Advanced Micro Devices, Inc. - Sunnyvale CA

International Classification:

H04L 108

US Classification:

370447

Abstract:

A network interface examines a field of a successfully transmitted frame following a contention resolution and transmission ordering among a plurality of nodes contending for transmission of a frame. The field indicates whether the successfully transmitting node has any additional frames to transmit. The number of backoff slots is maintained at a current value, rather than decremented, if the field indicates that the successfully transmitting node has an additional frame to transmit. The next frame to be transmitted is assigned the highest backoff slot. This procedure avoids re-contention and re-ordering when the contending nodes have additional frames to transmit, thereby improving overall network performance.

US Patent:

6877043, Apr 5, 2005

Filed:

Apr 4, 2001

Appl. No.:

09/825689

Inventors:

Tracy D. Mallory - Palo Alto CA, US
Matthew James Fischer - Mountain View CA, US

Assignee:

Broadcom Corporation - Irvine CA

International Classification:

G06F015/16

US Classification:

709251, 709252, 709253

Abstract:

A method for distributing sets of collision resolution parameters to be used for resolution of network access contention events among nodes of a non-centralized media access control shared medium network. A set of collision resolution parameters is provided which includes a sequence of fixed numbers for resolving a single network access contention event. A single collision signal slot master node is identified when one or more candidate collision signal slot master nodes exist. Collision signal slot request messages are sent from client nodes addressed to all network nodes. Collision signal slot assignment messages are sent from the master node to the client nodes. A collision resolution parameter set to be employed by that given client node is obtained at a given client node from within a received collision signal slot assignment message. Collision signal slot acknowledgment messages are sent from client nodes addressed to all network nodes. Collision signal slot drop messages are sent from client nodes addressed to all network nodes.

US Patent:

6975655, Dec 13, 2005

Filed:

Apr 4, 2001

Appl. No.:

09/826067

Inventors:

Matthew James Fischer - Mountain View CA, US
Tracy D. Mallory - Palo Alto CA, US

Assignee:

Broadcom Corporation - Irvine CA

International Classification:

H04L012/28
H04J003/06

US Classification:

370516, 37039562, 375356

Abstract:

A method of controlling data sampling clocking of asynchronous network nodes, each asynchronous network node having a local clock and transmitting and receiving packets to and from an asynchronous network according to an asynchronous network media access protocol. An asynchronous network node capable of transmitting and receiving packets on the asynchronous network is designated as a master node. Each non-master asynchronous network node which desires to synchronously transport packets across the asynchronous network is designated as a slave node. A master node clock of the master node is synchronized with a slave node clock of each slave node. Each slave node clock is continuously corrected compared with the master node clock to smooth slave clock error to an average of zero compared with the master clock as a reference using timestamp information from the master node. A derivative clock at the slave node is derived from the continuously correcting each slave node clock to control data sampling at the slave node.

US Patent:

6978318, Dec 20, 2005

Filed:

Jun 19, 2000

Appl. No.:

09/597371

Inventors:

Philip J. Keller - Fremont CA, US
Yatin R. Acharya - Sunnyvale CA, US
Matthew J. Fischer - Mountain View CA, US

Assignee:

Advanced Micro Devices, Inc. - Sunnyvale CA

International Classification:

G06F015/16

US Classification:

709250, 709227, 709236, 709253

Abstract:

A network interface includes a network medium interface operatively coupled to a software device driver arrangement, with a legacy media access controller (MAC) therebetween. The device driver arrangement includes a legacy MAC device driver configured to communicate with the legacy MAC, and an intermediate driver configured to communicate with the network medium interface. The intermediate driver and the network medium interface may communicate with one another by use of special frames, for example to send and receive control information. The special frames are formatted to pass through the legacy MAC, and include an identifier so that they can be identified at the intended destination, either the intermediate driver or the network medium interface. Upon identification, the control information is extracted at the destination. The network medium interface may include one or more MACs as well as one or more physical layer devices (PHYs).

US Patent:

7000031, Feb 14, 2006

Filed:

Apr 4, 2001

Appl. No.:

09/825851

Inventors:

Matthew James Fischer - Mountain View CA, US
Tracy D. Mallory - Palo Alto CA, US

Assignee:

Broadcom Corporation - Irvine CA

International Classification:

G06F 15/16
H04J 3/06

US Classification:

709248, 709209, 370503, 370509

Abstract:

A method of providing synchronous transport of packets between asynchronous network nodes. An asynchronous network node capable of transmitting and receiving packetson the asynchronous network is designated as a master node. Each non-master asynchronous network node which desires to synchronously transport packets across the asynchronous network is designated as a slave node. Best arrival times for packets transmitted from slave nodes to the master node are communicated from the master node to the slave nodes. Bestpacket assembly times for packets to be transmitted by the particular slave node to the master node in the future for the packets to be received by the master node at future master clock referenced best arrival times are determined. Packets for transmission at slave nodes are prepared and transmitted according to determined future bestpacket assembly time information.

US Patent:

7158759, Jan 2, 2007

Filed:

Dec 3, 2001

Appl. No.:

10/011004

Inventors:

Christopher J. Hansen - Sunnyvale CA, US
Joonsuk Kim - Menlo Park CA, US
Matthew Fischer - Mountain View CA, US
Jason A. Trachewsky - Menlo Park CA, US

Assignee:

Broadcom Corporation - Irvine CA

International Classification:

H04B 17/00
H04Q 7/30
H04Q 7/32
H04Q 7/34
H04Q 7/00

US Classification:

455 6711, 4554522, 4554521, 455 6713, 455 633, 455 62, 370329

Abstract:

A method and apparatus for dynamic frequency selection in a wireless communication system or network includes processing that begins when an access point determines interference on a wireless channel that is being used by the access point. When the interference exceeds an interference threshold, the access point provides a request packet to affiliated stations being serviced by the access point for channel spectrum information. The processing continues as the affiliated stations generate the channel spectrum information regarding each of the wireless channels in the wireless communication network. The processing proceeds then as the affiliated stations provide the channel spectrum information to the access point via the current wireless channel. The access point interprets the channel spectrum information to determine a desired wireless channel of the plurality of wireless channels within the wireless communication network. The access point then provides a selection packet to the affiliated stations via the current wireless channel to indicate that the access point will begin using the desired wireless channel at a particular future time.