32results about How to "Reduce protocol overhead" patented technology

A system and method are provided for aggregating Multimedia over Coax Alliance (MoCA) Medium Access Control (MAC) frames. The method sends a Multiframe Reservation Request (MRR) requesting a transmission time slot, and receives a grant in response to the MRR. Subsequent to sending the MRR, a plurality of MoCA MAC frames are accepted and assembled into a physical layer (PHY) burst packet that is transmitted in the granted time slot. A method is also provided for bundling client data packets into a MoCA MAC frame. The method sends a Bundledpacket Reservation Request (BRR) requesting a transmission time slot, and receives a grant in response to the BRR. Subsequent to sending the BRR, a plurality of client data packets are accepted and concatenated into a bundled MoCA MAC frame. The bundled MoCA MAC frame is transmitted in a PHY packet in the granted time slot.

A bi-directional reflective memory channel between a pair of storage controllers is used to maintain a mirrored copy of each storage controller's native buffer contents within the buffer of the other storage controller. To maintain such mirrored copies, buffer write operations that fall within a reflective memory segment of one storage controller are automatically reflected across this channel to the other storage controller for execution, and vice versa. The write operations are preferably transmitted across the reflective memory channel using a protocol that provides for error checking, acknowledgements, and retransmissions. This protocol is preferably implemented entirely in automated circuitry, so that the mirrored copies are maintained without any CPU intervention during error-free operation. When a failover occurs, the surviving storage controller uses the mirrored copy of the failed storage controller's native buffer contents to assume control over the failed storage controller's disk drives.

A communication system having one CAN bus and at least two devices interconnected by the CAN bus is described, at least one of the devices including: i) a CAN controller, which is suitable for transmitting CAN data frames over the CAN bus using a first physical protocol in a first operating mode; ii) an asynchronous serial communication interface unit, which is suitable for transmitting ASC data frames over the CAN bus using a second physical protocol in a second operating mode; iii) a first switching means, which is suitable for switching the first operating mode and the second operating mode depending on at least one agreement in effect between the device and at least one of the other devices; and iv) another switching means, which is suitable for switching the device to a third (restricted) operating mode, which differs from the first operating mode and the second operating mode, for powering up the device.

When a first mobile node is moved, it reports binding information including a compatible node identifier (virtual mobile guaranteed general network identifier and a node identifier) and a compatible position identifier (mobile guaranteed real network identifier identified on a network to which the first mobile node is moved, and a node identifier) to a first server which is assigned to the first mobile node. A second mobile node also reports the binding information to a second server. For communicating with the second mobile node to which a second server is assigned, if the destination address of a packet addressed to the second mobile node is designated with a compatible node identifier, the first mobile node acquires the binding information of the second mobile node from the second server. Then, the first mobile node converts the destination address of the packet into the acquired compatible position identifier and sets the compatible position identifier of the first mobile node as the source address of the packet. The first mobile node then transmits the packet.

The present invention relates to a method for routing at least a data packet in a wireless sensor network (10), the wireless sensor network (10) comprising: at least a source node (S) that is configurable to transmit at least a data packet; at least a destination node (D) that is configurable to receive the data packet transmitted by the source node (S), and interconnectable network nodes (si) between the source node (S) and the destination node (D) that are configurable to receive and forward the data packet, the method comprising the steps of: operating the network nodes (si) according to a sleep-active schedule comprising at least a sleep mode and an active mode, and configuring the network nodes (si) to have information on their own geographic location and the geographic location of the destination node (D), the method further comprising the steps of: dividing the wireless sensor network (10) into a plurality of disjoint areas (A0, AM-1, A1, A2) that are separated by boundaries; separating each area (A0, AM-1, A1, A2) into at en least two regions, the regions being an inner boundary region (I), a central region (C) and an outer boundary region (O); selecting forwarding nodes out of the network nodes (si) to route the data packet from the source node (S) to the destination node (D), such forwarding nodes being selected on the basis of their geographic location relative to the destination node (D) and the network nodes being synchronized relative to each other, and configuring the sleep-active schedule such that only those forwarding nodes that are selected to route the data packet in a given time window are operable in the active mode and all the other network nodes (si) are operable in the sleep mode.

A communication system and a method for operating a communication system, the communication system having a CAN bus and at least two devices connected with the aid of the CAN bus. Such a device has a CAN control unit, an asynchronous, serial communication (ASC) interface unit, and a switch. The CAN control unit is suitable for transmitting, in a first transmission mode, CAN data frames over the CAN bus with the aid of a first physical protocol. The asynchronous, serial communication interface unit or ASC interface unit is suitable for transmitting, in a second transmission mode, ASC data frames over the CAN bus with the aid of a second physical protocol. The switch is designed for switching over between the first transmission mode and the second transmission mode as a function of at least one agreement effective between the device and at least one other device.

The invention discloses a mixed media access control method of a wireless network. System channels are of time slot, and time slots with fixed cycle are distributed to non-competitive business nodes, non-competitive business data frame is transmitted in the mode of time division multiple access. Competitive business nodes transmit competitive business data frame in the competitive time slots by using the method of random competitive access. After the competitive business data frames conflict, the competitive business nodes send the competitive business data frame again under the condition that the estimated gain value of the channels is more than or equal to a given threshold. Or else the competitive business data is forwarded by a relay node; an access point buffers the signals received before, and realizes the data frame separation by methods of serial interference cancellation and minimum mean-square error detection. At the same time, a superimposed pilot channel estimation method is used by the competitive business data, no additional time slot is needed in the method, thus being convenient for orthogonal design. The method is suitable for the unexpected properties of competitive businesses and the cyclical properties of non-competitive businesses, and the mixed transmission of the two businesses can be supported.

The layer processing includes at least processing on a first, a second and a third layer. At the transmitter side, the third layer receives a packet, adds its header and forwards the packet to the second layer. The second layer performs segmentation and provides segmented data to the first layer, which maps the segmented data onto physical resources. The segmentation is based on the allocated resources. Retransmissions may take place on the third layer and thus, the third layer may re-segment the packet according to the received feedback for particular segments and provide the re-segmented data to the lower layers. Alternatively, the feedback information is provided to the second layer which then performs the segmentation by taking it into account. Correspondingly, the receiver performs re-ordering and re-assembly at the third layer for which it receives also control information from the second layer.

Provided is a hidden node detection method and apparatus in a wireless communication system, the apparatus including a sensing unit to sense a first communication device transmitting a data signal from among a plurality of communication devices sharing a wireless channel, a transmitter to generate a reception notification signal in response to the sensing, and transmit the reception notification signal to the a plurality of communication devices through a band identical to a transmission band of the data signal, and a controller to prevent a collision with the data signal transmitted from the first communication device through the wireless channel by delaying processing of a data transmission request when the data transmission request is input from a second communication device among the plurality of communication devices while maintaining the transmitting of the reception notification signal.