Abstract: A wireless communication system, apparatus, and methodology are described for enabling wireless communication station (STA) devices to generate a Physical Layer Protocol Data Unit (PPDU) that includes a resource unit (RU) having a size that is less than a spreading frequency block by using one or more predetermined pilot and/or data tone mapping plans to control how each pilot/data tone from the RU is distributed onto a disjoint set of pilot/data subcarriers forming a distributed RU included in the spreading frequency block, thereby accommodating transmission of wider bandwidth and multiple resource unit assignments in accordance with power spectrum density (PSD) limits provided for orthogonal frequency-division multiplexing (OFDM) modulated symbols supported by emerging 802.11 standards.

Abstract: Some embodiments provide, for a gateway datapath that executes on a gateway device to implement tenant logical routers for multiple different tenant logical networks and process traffic between the tenant logical networks and an external network, a method for managing QoS for the plurality of tenant logical networks. The method receives a data message for a particular tenant logical network. The method executes a set of processing stages to process the data message. The set of processing stages includes a processing stage for a particular tenant logical router of the particular tenant logical network. As part of the processing stage for the particular tenant logical router, the method uses a QoS data structure specific to the particular tenant logical router to determine whether to allow the data message. The gateway device stores at least one separate QoS data structure for each of a set of the tenant logical routers.

Abstract: Technology described herein can globally perform management of security tokens of plural nodes of a multi-node system. In an embodiment, a system can comprise an interconnected group of server nodes, and an administrator node communicatively connected to the interconnected group of server nodes and comprising a processor, and a memory that stores executable instructions that, when executed by the processor, facilitate performance of operations. The operations can comprise selecting a server node of the interconnected group of server nodes as a leader server node, resulting in a selection of the leader server node, in response, receiving, by the administrator node from the leader server node, a request for a new security token, and sending, to the leader server node, the new security token, and broadcasting, by the leader server node across a link layer discovery (LLDP) network, the new security token to additional nodes of the interconnected group of nodes.

Abstract: Methods and apparatuses providing a visual metric of the efficiency of a network of devices communicating through a wireless access point (AP). These apparatuses and methods may also determine and display pseudo-dynamic error vector magnitude (EVM) information for a network of wireless stations, including displaying a pseudo-dynamic constellation diagrams using EVM information. These methods and apparatuses may transmit a plurality of sounding packets from each of one or more radio devices different modulation types (e.g., BPSK, QPSK, 16 QAM, 64 QAM, 256 QAM and 1024 QAM), and receiving at least some of the sounding packets at a second radio device (e.g., an access point) and determining EVM information from the received sounding packets, and displaying (or providing for display) a constellation diagram including pseudo-dynamic EVM information that is a constrained approximation of actual EVM information.

Abstract: A computer system and method for managing a data request interface. The system includes a memory associated with the data request interface and coupled to a processor. The memory includes processor-executable instructions of the method for managing the data request interface. The method includes: receiving, from a first client device, a first signal including a primary authorization credential associated with a data record and a second signal including a request to generate an alternate authorization credential for use by a software module. The alternate authorization credential is associated with data retrieval constraints. The method includes generating the alternate authorization credential and configuring the data request interface to impose the data retrieval constraints for constraining data operations on the data record upon receipt of the alternate authorization credential.

Abstract: Methods, systems, and devices for wireless communications are described. Generally, the described techniques provide for improved handling of adjacent channel interference in multi-link aggregation scenarios. In accordance with the described techniques, a device may establish a set of wireless links for communication with a second device, the set of wireless links supporting parallel transmission during at least a first duration of a multi-link session, the set of wireless links including at least a first wireless link and a second wireless link. The device may modify a transmission parameter for the first wireless link or a clear channel assessment (CCA) parameter for the second wireless link, or a combination thereof. The device may then perform the CCA procedure on the second wireless link and transmit at least a first portion of the message on the first wireless link based on the modified transmission parameter or modified CCA parameter.

Abstract: A better compromise between encoding complexity and achievable rate distortion ratio, and/or to achieve a better rate distortion ratio is achieved by using multitree sub-divisioning not only in order to subdivide a continuous area, namely the sample array, into leaf regions, but using the intermediate regions also to share coding parameters among the corresponding collocated leaf blocks. By this measure, coding procedures performed in tiles—leaf regions—locally, may be associated with coding parameters individually without having to, however, explicitly transmit the whole coding parameters for each leaf region separately. Rather, similarities may effectively exploited by using the multitree subdivision.

Abstract: A communication apparatus has a communication function for performing wireless communication using one of a first mode of performing first communication with a partner apparatus via another apparatus, a second mode of performing second communication with the partner apparatus not via another apparatus, and a third mode of concurrently performing the first communication and the second communication. When the third mode is the operation mode of the communication function, the communication apparatus controls the communication function so as to activate a function of the second communication after executing processing to establish a connection for the first communication. When the connection has not been established even after a predetermined time has elapsed since the start of connection processing for the first communication, the function for the second communication is activated even if the connection for the first communication has not been established.

Abstract: This disclosure provides systems, devices, apparatus and methods, including computer programs encoded on storage media, for high efficiency (HE) beacons. HE supported access points (APs) and stations (STAs) may operate on resource deployments used for Wi-Fi technology and without support for legacy devices, also referred to as a greenfield deployment. An AP may identify updated capability information and transmit a HE physical layer convergence protocol (PLCP) protocol data unit (PPDU) including a beacon frame. A STA may receive, from the AP, the HE or EHT PPDU and identify an indication of change to a content or format of the beacon frame relative to a reference beacon frame. Based on the identified indication, the STA may then determine an updated content or format for the beacon frame and process the beacon frame or skip processing for one or more portions of the beacon frame.

Abstract: A configuration synchronization method includes a first extender network device transmitting an extender configuration version to a root network device; the root network device determining whether the extender configuration version is the same as a second root configuration version currently owned by the root network device; and when the extender configuration version is different from the second root configuration version, the root network device transmitting the second root configuration version and a plurality of root network configurations corresponding to the second root configuration version to the first extender network device; a first extender network device updating a plurality of extender network configurations thereof to be the plurality of root network configurations, and updating the extender configuration version thereof to be the second root configuration version.

Abstract: Examples relate to providing selective access to resources. In one example, a computing device may: receive, from a client application, a request to access a first resource server, the request including a client access token; identify a first set of permissions specified by a client topology, the client topology specifying: the first resource server; the first set of permissions for accessing, by the client application, the first resource server; a second resource server; and a second set of permissions for accessing, by the first resource server, the second resource server; provide the client application with a first access token specifying the first set of permissions and the first resource server; receive, from the first resource server, a request to access the second resource server, the request including the first access token; and provide the first resource server with a second access token specifying the second set of permissions.

Abstract: In an automation-communication network, at least one distribution node comprises input/output interfaces each connected to at least one network segment. In a first network segment a first subscriber and in a second network segment a second subscriber are arranged. Data are exchanged between the first and the second subscriber by telegrams realized as scheduled telegrams and unscheduled telegrams. The distribution node receives an unscheduled telegram on an input/output interface and sends an unscheduled telegram on a further input/output interface. The distribution node determines a transmission duration for transmission of the unscheduled telegram. The distribution node transmits the unscheduled telegram. Prior to transmission, the distribution node deposits a first telegram information in a data field. The distribution node fragments the unscheduled telegram if the telegram cannot be transmitted within a time slot.

Abstract: A conversion pipeline includes a media input stage, a packetizer, a MAC engine and a PHY interface. The media input stage is configured to receive from a media source a sequence of media frames carrying media content. The packetizer is configured to convert the media frames into a sequence of Ethernet packets by generating headers and appending portions of media frames to corresponding generated headers, including appending a first portion of a first media frame to a first generated header before the first media frame is fully received. The MAC engine is configured to commence outputting a first Ethernet packet as an uninterrupted unit, the first Ethernet packet including the first header and payload bits corresponding to the first portion of the first media frame, before the first media frame is fully received. The PHY interface is configured to transmit the Ethernet packets over a network.

Abstract: A communication apparatus has a communication function for performing wireless communication using one of a first mode of performing first communication with a partner apparatus via another apparatus, a second mode of performing second communication with the partner apparatus not via another apparatus, and a third mode of concurrently performing the first communication and the second communication. When the third mode is the operation mode of the communication function, the communication apparatus controls the communication function so as to activate a function of the second communication after executing processing to establish a connection for the first communication. When the connection has not been established even after a predetermined time has elapsed since the start of connection processing for the first communication, the function for the second communication is activated even if the connection for the first communication has not been established.

Abstract: Aspects of the disclosure provide an apparatus for wireless communication. The apparatus includes a transceiver and a processing circuit. The transceiver is configured to transmit and receive wireless signals. The processing circuit is configured to detect an error of a previous scheduled transmission of data units from the apparatus to another apparatus. The other apparatus provides scheduled resources for transmission between the two apparatuses. Further, the processing circuit is configured to determine resources that are scheduled by the other apparatus for the apparatus to perform retransmission, and provide one or more of the data units in the previous scheduled transmission to the transceiver for retransmission using the scheduled resources.

Abstract: The systems and methods described herein provide an audio system and modules that include speakers that can be packaged in new locations, and/or that can be driven by a local amplifier (amp). The new audio system can be easily upgraded with more modules inserted into the speaker network. For example, the custom system can increase capacity by replacing a trim panel with a new integrated trim panel having a module with one or more smaller speakers and the local amp. A control processor can detect the modules, which may include a digital signal processor (DSP), an amp, and/or at least one speaker.

Abstract: An example method includes generating, by a first user device, a first number representing a contention resolution priority for the first user device contending for at least one first resource over a first data period for transmitting a packet of data in a device-to-device (D2D) wireless network, determining if a second device, in the D2D wireless network, is contending for resources overlapping with the at least one first resource of the first data period, if the second device is contending for resources overlapping with the at least one first resource of the first data period, determining if a second number representing a contention resolution priority for the second user device is greater than the first number, and if the second number is greater than the first number, inhibiting the first user device from communicating using the at least one first resource of the first data period.

Abstract: A distributed network management method for a vehicle is provided. The distributed network management method includes a first step, a second step, a third step and a fourth step. The first step is for preforming a re-configuring action and a pre-defining action to a plurality of network messages transmitted through a plurality of nodes. The second step is for defining a leading node form the nodes. The third step is for detecting a failed node from the nodes. The fourth step is for defining at least one idle node by the leading node according to a task load of each of the nodes, thereby assigning a task of the failed node to the idle node.

Abstract: Methods, systems, and apparatus for providing airtime fairness in a telecommunications network are disclosed. In one aspect a method includes determining, by an access point, respective transmission rates of multiple stations configured to wirelessly communicate with the access point; determining, by the access point and for each of the multiple stations, a weight of the station that is proportional to the respective transmission rate of the station; and transmitting, wirelessly by the access point and to each of the multiple stations, one or more packets to the station during an airtime allocation to the station, wherein the amount of one or more packets transmitted during the airtime allocation corresponds to the weight of the station and a size of queued packets for the station.

Abstract: A method and apparatus schedule user equipment uplink transmissions on an unlicensed carrier. Listen before talk can be performed to determine when a subframe is available for uplink transmission. A sounding reference signal can be transmitted in an initial discrete Fourier transform spread orthogonal frequency division multiplexing symbol of the subframe when listen before talk indicates that the subframe is available. A physical uplink shared channel can be transmitted in at least a portion of a remaining part of the subframe.

Abstract: A method of pixel control which reduces the number of DMX control channels required for generation of artistic pixel patterns displayed on a large number of pixel LEDs is described. Further described are a set of control parameters which facilitate the introduction of pixel control and sophisticated pixel pattern generation without a costly DMX controller upgrade. Also described is a device for generating lighting effects. The device may be portable, battery-powered, radio-controlled and small enough to easily hide in most theatrical and film sets, set pieces, props, and practicals. The device may be configured to process DMX data for controlling and generating graphical patterns among pixel LEDs based on the set of one or more control parameters. The method and device relocate the processing of the DMX data from the DMX controller to one or more individual hardware drivers for the pixel LEDS.

Abstract: A block processing pipeline in which macroblocks are input to and processed according to row groups so that adjacent macroblocks on a row are not concurrently at adjacent stages of the pipeline. The input method may allow chroma processing to be postponed until after luma processing. One or more upstream stages of the pipeline may process luma elements of each macroblock to generate luma results such as a best mode for processing the luma elements. Luma results may be provided to one or more downstream stages of the pipeline that process chroma elements of each macroblock. The luma results may be used to determine processing of the chroma elements. For example, if the best mode for luma is an intra-frame mode, then a chroma processing stage may determine a best intra-frame mode for chroma and reconstruct the chroma elements according to the best chroma intra-frame mode.

Abstract: A plurality of networks each having a host are connected to achieve a transparent transaction between devices belonging to the different networks. A target apparatus includes a station and a host. In response to a get device handle request from an initiator apparatus, the station acquires, from the host, configuration information of a target device and relays transactions between the initiator apparatus and the target device, without requiring involvement of the host.

Abstract: An error detection method of a variable-length coding (VLC) code stream includes at least the following steps: decoding a data frame of the VLC code stream; and determining whether the data frame is erroneous according to length information of the data frame and a bit number of decoded data of the data frame. According to the method, the present invention realizes the objective of performing error detection upon data frames during the decoding process.

Abstract: Methods and apparatus for burst-mode admission control using token buckets are disclosed. A work request (such as a read or a write) directed to a work target is received. Based on a first criterion, a determination is made that the work target is in a burst mode of operation. A token population of a burst-mode token bucket is determined, and if the population meets a second criterion, the work request is accepted for execution.

Abstract: Systems and methods for scheduling network communications in a managed network can include a Network Controller discovering a plurality of network nodes; the Network Controller classifying the discovered network nodes into two or more classifications of node for node-level prioritization of network communications; the Network Controller receiving reservation requests from at least some of the plurality of network nodes, wherein the reservation requests request one or more time slots for their respective network nodes in an upcoming communication window; and the Network Controller assigning time slots in the upcoming communication window to one or more network nodes in response to reservation requests, wherein the assignment is based on a priority of the network nodes and wherein the priority is assigned to the nodes according to their classification.

Abstract: Techniques for a mixed audio conference are described. An apparatus may comprise an audio video multipoint control unit to mix call information from multiple call connections established over a packet-switched network for a conference call. The apparatus may comprise a telephony gateway communicatively coupled to the audio video multipoint control unit. The telephony gateway may establish a bridge connection with a conference bridge servicing a call connection over a circuit-switched network, the telephony gateway to translate call information from the call connection for use by the audio video multipoint control unit. Other embodiments are described and claimed.

Abstract: A multimedia bitrate adaption method for individual users wherein only a set of predetermined bitrates may be selected as the multimedia bitrate of the user. The predetermined bitrates are quantized into exponentially distributed levels, and the users' experiences corresponding to the predetermined bitrates are with the same intervals, thereby increasing the service capacity and improving user satisfaction.

Abstract: A method of processing first and second record packets of real-time information includes computing for each packet a deadline interval and ordering processing of the packets according to the respective deadline intervals. A single-chip integrated circuit has a processor circuit and embedded electronic instructions forming an egress packet control establishing an egress scheduling list structure and operations in the processor circuit that extract a packet deadline intervals, place packets in the egress scheduling list according to deadline intervals; and embed a decoder that decodes the packets according to a priority depending to their deadline intervals.

Abstract: Embodiments of a local interface unit are disclosed that may allow for managing credits and tokens as part of flow control method. The local interface unit may include a transmit unit and a receive unit. The transmit unit may be configured to receive credits and tokens, determine an available number of credits based on the number received tokens, determine an available number of tokens based on the number of received tokens, and send the available credits to an arbitration unit. The available credits may then be updated, by the transmit unit in response to receiving a selected transaction from the arbitration, and the transmit unit may then transmit the selected transaction, and update the available credits and the available tokens once the transaction has been sent. The receive unit may be configured to send credits and tokens to a transmit unit, and receive a transaction sent by a transmit unit.

Abstract: In a central controller, a method for managing resources comprising sending a request to a node in a domain controlled by the central controller, wherein the request requests at least a portion of a resource of the node, receiving a response from the node, wherein the response contains information on the availability of the portion of the resource, and storing the information on the availability of the portion of the resource for use in establishing a multiprotocol label switching (MPLS) label switched path (LSP).

Abstract: A scaleable network monitoring system is discussed. The network monitoring system identifies network monitoring information for the network elements being monitored. By storing only a non-redundant subset of the identified network information in memory, the network monitoring system is able to monitor a much larger group of network elements than is possible with conventional monitoring systems which are burdened by memory constraints. The scaleable network monitoring system also employs a multi-threaded architecture that dynamically spawns an array of multi-technology monitoring sub-systems.

Abstract: A method and an arrangement for transferring information including delay sensitive data, such as speech and video data, in a packet radio service is provided. Data blocks are transmitted from a mobile station to a radio resource entity during a first active data transfer period using an uplink temporary block flow (TBF) connection. The uplink TBF connection is maintained during a passive period that follows the first active data transfer period, wherein during the passive period the mobile station does not send data blocks to the radio resource entity.

Abstract: A cellular communications system is described in which a mobile cellular device can, if necessary, obtain cell measurements for cells contained within a first cell list after it has received a second cell list. The mobile device then reports the cell measurements for cells within both lists so that a best candidate cell is less likely to be discarded in a cell handover procedure. A network node is also disclosed that can receive cell measurements for cells within a first cell list after the node has issued a second cell list. The node then uses the received cell measurement data to control a handover procedure.

Abstract: A communication management apparatus that manages transmission of data in a network in which plural communication nodes are connected via a transmission line in a ring shape, the apparatus including: a network-presence checking unit that transmits a network-presence-check frame in broadcast and generates network connection information indicating a connection state among the connection nodes from a received network-presence-check acknowledge frame, a token-circulation-order determining unit that determines token circulation order; a setup processing unit that performs setup processing for notifying each of the communication nodes of a token circulation destination; a data-frame-communication processing unit that performs transmission and reception of a data frame using a token frame; and a line-connection managing unit that disables, when the network has a ring configuration, any one of ports of any one of the communication nodes to prevent a connection state of the network from becoming a ring shape.

Abstract: Various embodiments provide an apparatus and method for adapting wireless sensor network device operation to ambient RF noise. An example embodiment includes: initializing a noise threshold value to a default value; detecting an ambient RF noise level on a plurality of channels of a wireless network device; if the ambient RF noise level detected on a pre-determined number of channels is above the noise threshold value, adjusting the noise threshold value by an increment and retesting the ambient RF noise level on the plurality of channels; if the noise threshold value exceeds a pre-determined maximum noise threshold value, suspending data communications by the wireless network device; and if the ambient RF noise level detected on a pre-determined number of channels is below the noise threshold value, retaining the noise threshold value and enabling data communications by the wireless network device.

Abstract: In the method according to the invention for communicating between installations, which are organized in an order according to a sortable feature, for example installation numbers, in a wind farm, in which information transmitted by an installation in the form of a message is received by all other installations in the wind farm, a cyclically recurring, temporal transmission interval is set up. A point in time in the transmission interval at which the installation can transmit a message is assigned to each installation on the basis of the position thereof in the order, wherein points in time are organized from the start of the transmission interval, starting from the installation number at the first position in the order, in accordance with the position in the order. The start of the transmission interval is synchronized in all installations using a message from the installation at the first position in the order.

Abstract: A method and apparatus are described including transmitting a request-to-send signal, determining if a clear-to-send signal and a reverse direction transmission request signal have been received, transmitting first data, a first block acknowledgement request signal and a reverse direction grant signal responsive to the first determination, determining if a first block acknowledgement signal, second data and a second block acknowledgement request signal have been received, transmitting a second block acknowledgement signal responsive to the second determination, determining if a third block acknowledgement signal has been received and transmitting a fourth block acknowledgement signal responsive to the third determination.

Abstract: A wireless system and method including a medium access control (MAC) layer adapted to recover service in restricted channels.

Abstract: A method and system for processing session initiation protocol messages including receiving a session initiation protocol message by a front end, parsing the session initiation protocol message by the front end, grouping the token types and the token contents in the session initiation protocol message respectively, and setting up corresponding links between the token types and the token contents, wherein the session initiation protocol message, after parsing, is transformed to the session initiation protocol offload engine message with a session initiation protocol offload engine message header part, for storing message level information, a token type part, for storing token type information, wherein it comprises a plurality of fixed-length entries, and a token content part for storing token contents, wherein it comprises a plurality of variable-length entries, and processing the transformed session initiation protocol offload engine message at the server end.

Abstract: A communication management apparatus that manages transmission of data in a network in which plural communication nodes are connected via a transmission line in a ring shape, the apparatus including: a network-presence checking unit that transmits a network-presence-check frame in broadcast and generates network connection information indicating a connection state among the connection nodes from a received network-presence-check acknowledge frame, a token-circulation-order determining unit that determines token circulation order; a setup processing unit that performs setup processing for notifying each of the communication nodes of a token circulation destination; a data-frame-communication processing unit that performs transmission and reception of a data frame using a token frame; and a line-connection managing unit that disables, when the network has a ring configuration, any one of ports of any one of the communication nodes to prevent a connection state of the network from becoming a ring shape.

Abstract: Systems, methods, devices, and computer program products are described for handling of access terminals on an out-of-band piconet within a femto-proxy architecture. A femto-proxy system includes a femtocell (a femto access point, or FAP) and one or more out-of-band (OOB) proxies. One of the OOB proxies is configured to act as a master of an OOB piconet, through which various services are provided, including services to support the femtocell operation of the femto-proxy system. For example, the OOB piconet is used to facilitate lower power access to the macro communications services provided through the femtocell. In some cases, a combination of connected and inactive OOB operational modes are used to support an expanded number of slave access terminals on the piconet, where some of those slaves are operating in an active WWAN mode and others are operating in an idle WWAN mode. For example, parked mode may be used for idle WWAN mode access terminals.

Abstract: A method of requesting a radio resource in a wireless communication system is provided. The method comprises setting a timer's expiry time, transmitting a radio resource request message to a base station, starting the timer and retransmitting the radio resource request message to the base station if a radio resource allocation message is not received until the timer expires, wherein the expiry time may be set variably based on a communication state.

Abstract: Apparatus comprising a Session Initiation Protocol agent (9) arranged to send and receive Session Initiation Protocol messages to and from peer Session Initiation Protocol agents. The apparatus is configured, for a Session Initiation Protocol message to be sent, to translate (10) one or more header fields of the message into an alternative format and to include (11) the translated field(s) within or prefixed to the message, together with the untranslated field(s).

Abstract: Remote control based output selection techniques are described in which an output to a display device is selected based on identification of a remote control device that is manipulated by a user. In an implementation, each of a plurality of remote control devices is associated with a respective client device in an audio visual system. When a user manipulates one of the plurality of remote control devices, the manipulated remote control device is detected and a corresponding client device is determined. Then, an output to a display device is set to present audio visual data from the determined client device. In another implementation, when a manipulated remote control device is identified, a user interface for output on the display device is configured according to the identified remote control device and/or the functional capabilities of the identified remote control device.

Abstract: A method is provided in one example embodiment and includes communicating an access request message associated with a mobile node, receiving an access accept message that includes domain name data associated with the mobile node, and communicating a packet data protocol (PDP) context accept message for a tracking PDP context associated with the mobile node without associating an internet protocol (IP) address to the mobile node. The tracking PDP context identifies that the mobile node is available to receive network data. In more particular embodiments, the access request message includes an International Mobile Subscriber Identity (IMSI) associated with the mobile node, and the domain name data includes a fully qualified domain name. In still other embodiments, the tracking PDP includes a protocol configuration option (PCO) indicating that an IP address is not required for the mobile node.

Abstract: A method, apparatus, and computer program embodied on a computer-readable medium to create an uplink message to be transmitted to a base station, the created uplink message comprises a sounding reference signal based on accessed data. An uplink scheduling grant signal is received via downlink, from the base station, in response to the transmission of the uplink message. An uplink data transmission is transmitted to the base station responsive to the received uplink scheduling grant signal.

Abstract: Provided are methods and systems for substituting programs within an existing multi program transport stream (MPTS). Methods can include identifying a first packet associated with a first input program, determining if the first packet is a packet to be replaced, substituting a second packet for the first packet if the first packet is the packet to be replaced, and applying a timestamp at the stream processor to the second packet with a time for the second input program.

Abstract: A system and method of transmitting packets from a wireless device is provided. According to a broad aspect, the wireless device is to transmit a packet on a communication channel during a time window based on whether or not the communication channel is expected to be torn down during the time window. If the communication channel is not expected to be torn down during the time window, then the wireless device transmits the packet late in the time window. However, if the communication channel is expected to be torn down during the time window, then the wireless device transmits the packet during the time window just prior to when the communication channel is expected to be torn down. This prevents having to re-establish the communication channel merely to transmit the packet if the communication channel is torn down.

Abstract: In a data communication system that performs data communication between a master station and slave stations in a token passing system employing an Ethernet (registered trademark), when a communication processing unit of a master station subjects processing for circulating a token frame between the master station and slave stations and receiving data from the slave stations to retry processing, the communication processing unit subjects the processing to the retry processing without transferring data received from the slave stations to a data processing unit that performs transmission and reception of data between the data processing unit and an arithmetic processing device.