Abstract: A contention-based network which allows real-time traffic to exist as multiple independent linked-list chains or under certain conditions to be assembled into multiple linked-list chains. A time separation is enforced between the various multiple chains, which are limited to a predetermined maximum number of stations that each can have in order to allow non-real-time stations to obtain timely access to the medium. Ones of the multiple chains may also be joined into a single chain. Blackburst contention is used to enable a chain to be reconstituted robustly from non-anticipated interruptions, such as the failure of one of its stations.

Abstract: A communication system includes devices configured to communicate with each other through a temporal sequence of frames. Each of these frames includes multiple sub-channels and the total number of sub-channels in a given frame is dynamically determined based on a transmission schedule. Furthermore, the transmission schedule is calculated by the devices based on transmission lists that are exchanged between the devices. For example, a first transmission list for a first device includes a first group of sub-channels reserved by the first device, and a second group of sub-channels reserved by a set of devices communicating with the first device.

Abstract: Wireless stations (108-1-108-N) contending for exclusive access for a predetermined period of time (S232) to transmit on a communication medium (112) are regulated by a common external controller (104) using a single timing parameter (S204). Attempts at transmission access are preceded by respective delays that are expired simultaneously and at a common rate by the stations at times when the stations sense the medium to be idle (S224). The delays are pseudo-randomly selected to avoid collisions among stations in their respective access attempts (S208). Default, initial values of the respective delays (S204) applied to the stations, when multiplied by the respective expected number of transmission attempts by the stations over the long term over periods of time when no transmission attempt is unsuccessful, yield respective products equal to a constant value common to all stations (S312). The default values therefore serve as a knob by which the controller regulates air time opportunity.

Abstract: A method and corresponding system for communicating between stations in a network are presented. The method includes providing repeated beacon transmissions from a coordinator station for coordinating transmissions among a plurality of the stations; transmitting from a first station to a second station during a time slot assigned to the first station by at least one of the beacon transmissions; and transmitting from the first station information that grants permission to the second station to transmit during at least a portion of a time slot assigned to the first station.

Abstract: Methods and apparatus for implementing a robust unicast/broadcast/multicast protocol are provided. In one aspect, a method of avoiding collision of intra-basic service set unicast, broadcast or multicast transmissions notifies stations in the basic service set of a reserved transmit opportunity for a unicast, broadcast or multicast transmission. Transmissions from at least one station in the basic service set are deferred until after the reserved unicast, broadcast or multicast transmit opportunity.

Abstract: To increase bandwidth, a channel, which normally is limited to contention-free transmissions, is used for other purposes during times when it is not needed for contention-free transmissions. Although the channel is located in a contention-free portion of a beacon cycle, supplemental uses of this channel include the contention-based transmission of data that normally would be sent during a contention portion of the cycle. These transmissions include those made under the CSMA protocol.

Abstract: One embodiment of the present invention provides a system for facilitating proportionally fair-share time slot reservations with a fast increase, slow decrease rate controller in an ad hoc dynamic wireless broadcast network. During operation, the system determines local time slot demand, based on transmitted and queued data corresponding to one or more previous decision points. Next, the system broadcasts the local time slot demand to one or more neighbors. The system also determines neighbor time slot demands, where a respective neighbor time slot demand indicates a particular neighbor's local time slot demand corresponding to one or more previous decision points. Next, the system determines neighborhood time slot demand, based on the local time slot demand and the neighbor time slot demands. Next, the system determines allowable reserved time slots based on the local time slot demand and allowable reserved time slots corresponding to one or more previous decision points.

Abstract: A channel allocating method for random access is disclosed, which is suitable for allocation of uplink RACH in a radio access network and by which random access processing performance in a radio access network is enhanced using RACH of new structure. The present invention includes the steps of setting up a channel area (Ic) dedicated for new access attempt among random access channels of a prescribed frame (t) and allowing a mobile terminal to attempt access to an access point via a prescribed random access channel corresponding to the channel area (Ic).

Abstract: In some embodiments of the present invention, asynchronous network nodes and synchronous network nodes coexist on a shared media network.

Abstract: A method and apparatus for providing quality of service over a contention access period of a wireless personal area network is provided herein. Particularly, the layers above the MAC are allowed to reserve portions of a contention access period (CAP) in order to schedule their QoS actions cooperatively thereby avoiding the dependence on the MAC for QoS performance. By using cooperative scheduling, a node can send a QoS packet from the QoS_Layer to the MAC, and know that it will be transmitted according to the specified QoS requirement. As a result, whenever a node sends a QoS packet in the reserved portion of the CAP, the channel will be guaranteed to be free from competing nodes' packets because those competing nodes will delay their transmissions based on the shared schedule.

Abstract: In one aspect, a method for determining a leading subscriber in a network consisting of a plurality of network elements, with initially the same privileges and tasks is provided. A request message is sent to all network elements, the request message being marked by a sequence number taken randomly from a first set of numbers. Request messages sent by the remaining network elements over a pre-defined period of time are receive. The sequence number transmitted during the interval is compared with the intrinsic sequence number transmitted during the first stage. If the intrinsic sequence number has the numerically highest value in comparison with all of the received sequence numbers, the network element in question is identified as the leading subscriber.

Abstract: An arbiter system may include a first arbiter, a second arbiter, and selection logic. The first arbiter may be configured to select a first data identifier from among a group of data identifiers that are associated with a first bandwidth. The second arbiter may be configured to select a second data identifier from among another group of data identifiers that are associated with a second bandwidth. The selection logic may be configured to periodically select the first data identifier and the second data identifier so that the first data identifier and the second data identifier are respectively selected in proportion to the first bandwidth and the second bandwidth.

Abstract: A wireless resource allocation apparatus and method which maintain quality of service (QoS) in a wireless communication network are provided. The wireless resource allocation method includes calculating the number of medium access slots (MAS) to be allocated to at least one of a plurality of divided zones of at least one superframe, designating a reference location for MAS allocation to divided zones out of the plurality of divided zones of the superframe based on the calculated number of medium access slots, and allocating the medium access slots to the divided zones based on the designated reference location. Accordingly, more uniform service intervals can be supported, and thus efficient MAS resource allocation can be performed to satisfy media access control (MAC) based QoS requirements.

Abstract: This invention pertains to a method for collision avoidance in local Ethernet networks, such as a home automation network, having a personal computer and a plurality of control devices attached. In such a network, when a management message is broadcast from the host personal computer to all connected control devices, each one of such devices must reply with a response to the host computer. There is, however, a probability that responses might collide, leading to data loss. The present invention discloses a method to generate delayed responses to the sender from each control device, where an individual device's delay is computed in accordance to a unique value contained in its MAC address. The method will guarantee different delay times for all attached control devices, and hence a collision-free operation.

Abstract: A low-latency, peer-to-peer TDM bus including one or more data lines and one or more control lines is provided. Attached devices access the bus sequentially in order of their bus addresses. During a device's access period, if the device has data to transmit, the device places its address on the data lines, asserts a START signal on the bus, and proceeds to transmit data to the other devices on the bus. When the data transmission is completed, the device asserts an END signal on the bus, thus passing control of the bus to the next device in the sequence. If the device has no data to transmit, the device simply places its address on the data lines, asserts the START signal, and asserts the END signal, and control passes directly to the next device in line. In this manner, each device has an opportunity to transmit on the bus.

Abstract: A novel method for coordinating the delivery of frames to and the receipt of frames from a power-saving station in a wireless local-area network (LAN) is disclosed. The illustrative embodiment establishes a wake-up schedule for a power-saving station based on a temporal period and temporal offset that reduces the frequency with which multiple stations in a network wake up simultaneously, thereby reducing traffic delays and power consumption. The illustrative embodiment is particularly well-suited to networks with traffic that has delay/jitter quality-of-service (QoS) requirements (i.e., voice calls, videophone calls, etc.).

Abstract: A method, apparatus and computer program product for providing a prioritized MAC protocol for a WLAN or wireless mesh using a time filtering technique wherein a time limit (Advanced Interval For Reservation or AIFR) is imposed on the time prior to the expiration of data channel's NAV when a data channel is considered ‘almost idle’. The same AIFR limit applies to all CC-RTS of the same priority, and a higher priority CC-RTS will have a longer AIFR.

Abstract: A packet switch arbitration system and method for arbitration in a packet switch. In one aspect, a method of issuing grants to an ingress port is disclosed in which a first grant request and burst signal are activated at an ingress port having more than one word available for transfer through the switch. A first grant is issued to the ingress port on a first interval. A subsequent grant is issued to the ingress port on a subsequent interval, where the subsequent grant is issued before the ingress port has validated the first grant request.

Abstract: A method for prompt re-direction of uplink access of a specific user equipment is disclosed. For initial random access to a network, if a user equipment transmits a preamble, which includes information related to random access, to a network node, the network node sends grant/rejection information of the preamble and re-direction information as a response message to the preamble. In comparison with the related art which controls a rush of an access request of the user equipment through a second response message from the network node, since the rush of an access request is controlled by a first response message in the present invention, it is possible to promptly deal with abnormal communication status, thereby improving communication efficiency.

Abstract: An arrangement avoids contention on a communication medium among devices including at least a transmitter and a receiver. The arrangement involves a first portion configured to instruct a receiver to indicate that the communication medium is busy for a time period substantially longer than an actual frame transmission period being sent from the transmitter to the receiver, and a second portion configured to prohibit the receiver from transmitting on the communication medium during the time period.

Abstract: The present invention relates to a state machine which has a dual process which receives and concurrently processes ad-hoc and infrastructure processes. The dual process state concurrently executes both processes by either over-clocking a media access control core, or by routing the processes to multiple media access control cores for processing. The state machine contains an ad-hoc process state which accepts either an ad-hoc or an infrastructure signal, and either processes the signal if the received signal is an ad-hoc signal, or transfers control to an infrastructure process state for processing if the received signal is an infrastructure signal. The state machine also contains an infrastructure process state which accepts either an ad-hoc or an infrastructure signal, and either processes the signal if the received signal is an infrastructure signal, or transfers control to an ad-hoc process state for processing if the received signal is an ad-hoc signal.

Abstract: A wireless communication system and method is disclosed. The system and method includes at least one base station controller setting resource allocation priority and producing a carrier loading information request in response to a request made by a mobile unit; a plurality of base stations coupled to at least one base station controller, each of the plurality of base stations operates on a plurality of carriers, at least one candidate base station transceiver of the plurality of base stations receiving the carrier loading information request, determining its carrier loading information, and responding with a carrier loading information response; and the at least one base station controller operating to assign the mobile unit to at least one candidate carrier within the one responding candidate base station of the plurality of base stations based upon both set resource allocation priority and received carrier loading information.

Abstract: A method includes receiving a first message at a router in a mesh network and synchronizing the router to a plurality of time slots using the first message. The method also includes repeatedly incrementing a network reference value at each time slot up to a maximum value and then decrementing the network reference value at each time slot down to a minimum value. In addition, the method includes broadcasting a second message at the router when the network reference value has a specific value that is associated with a unique identifier of the router.

Abstract: A system and method for minimizing latency for direct group communications, such as push-to-talk (PTT) calls, among a group of wireless telecommunication devices on a wireless telecommunication network. The wireless telecommunication device selectively requests and then receives an open dedicated broadcast channel for an outgoing communication, which can include a group communication stream to a communication server that receives and creates a group communication to all wireless telecommunication devices of the designated group. The wireless telecommunication device selectively receives a broadcast channel based upon a predetermined probability, and assigns a greater probability of receiving an open broadcast channel for requests to transmit group communication streams than for requests to open a broadcast channel that are not for a group communication.

Abstract: A method of operating in a network in which a plurality of stations communicate over a shared medium (e.g., using a carrier sense multiple access (CSMA) service). The stations contend for access to the shared medium using a contention procedure that relies on a priority level, wherein transmissions with a lower priority level have a reduced chance of gaining access to the shared medium during a contention process. Selected stations are given the capability of temporarily promoting the priority level of transmissions they are attempting to make. The priority level is increased during an interval to reduce the chance that other stations gain access to the shared medium during that interval, and the priority level is restored to its normal level following the interval.

Abstract: A system and method for providing spatial reuse in a wireless network for communicating compressed and uncompressed audio/video is disclosed. A bandwidth reservation request for data communication with a receiver to a coordinator is transmitted. A first response indicating availability of the receiver for the data communication is received. A channel is listened to by a station for channel busy indication (CBI) messages transmitted by other stations in the wireless network. A local channel occupation report comprising data indicative of one or more time periods during which one or more other stations in the wireless network are scheduled to transmit data messages is transmitted to the coordinator. A second response comprising data indicative of one or more allocated channel time slots is received. Audio and/or video (A/V) data is transmitted to the receiver during the allocated channel time slots.

Abstract: An ad hoc network organizes itself to provide communications without need for an a priori designated central control mechanism or base stations. Such self-organization is challenging in a multihop ad hoc network having member nodes that are highly mobile and widely distributed. A Synchronous Collision Resolution (SCR) protocol is well suited to provide efficient medium access control is such networks. SCR is an access protocol that archives high capacity collision free access using a signaling approach that creates a random cellular-like network after each signaling period. In use, the present invention provides quality of service and supports energy conservation for the mobile nodes.

Abstract: A communication system includes devices configured to communicate with each other through a temporal sequence of frames. Each of these frames includes multiple sub-channels. Note that a given device in the devices is configured to select sub-channels to reserve based on a nearest-neighbor spacing between the sub-channels to be reserved and/or a switching latency between data in-flow to the given device and data out-flow from the given device. Furthermore, the given device is configured to dynamically reserve the selected sub-channels on a frame-by-frame basis for up to N frames.

Abstract: A wireless data transmission method includes providing a plurality of radio frequency transmitters. A receiver is provided to receive transmissions from the transmitters. A data format including a plurality of transmission time slots is defined. Each of the transmitters is caused to independently select one of the time slots. The transmitters are used to transmit the transmissions to the receiver in the independently selected time slots.

Abstract: A communication apparatus, which improves the throughput of a whole communication system while performing contention distributed control which provides equality of a transmission chance by observing a medium occupation state, is provided. Thus, the communication apparatus according to the present invention comprises: a back-off process section for performing, using a contention window, a regular back-off process which is performed at transmission of a transmission frame and a pseudo back-off process which is performed in a pseudo manner when the transmission frame is not transmitted; a medium information obtaining section for obtaining, by the pseudo back-off process, medium information indicative of a state of the transmission line medium when the transmission frame is not transmitted; and a medium state determination section for determining the state of the transmission line medium using the medium information to obtain determination information.

Abstract: A wireless communication system using channel access based on a contention approach and method thereof is disclosed, which allocates plural sets of time slots in a predetermined contention interval, wherein each set of time slots further includes plural adjacent overlapped time slots. A channel requester transmits a contention message to a channel allocator at a time slot based on an interleaved method after the channel requester completes count down of a predetermined time, so that the positions of the headers of the contention messages in the adjacent time slots of each set of time slot are different. Thus, if the contention message transmitted by the channel requester collides with the contention message of the adjacent time slot, the channel allocator can parse the headers of the collided contention messages and respectively allocate plural special channel times for communicating with the channel requesters.

Abstract: A method for arbitrating access to a time slot in a time division multiple access network in an asynchronous hub with a bus guardian is provided. The method including receiving signals from competing nodes claiming access to the same time slot at the bus guardian of the asynchronous hub, selecting one of the nodes based on a priority scheme, and relaying a message from the selected node and blocking the message from the non-selected node.

Abstract: A system controls the transfer of data. The system receives a request to transfer data and determines whether a counter value equals or exceeds a threshold. The counter value represents an amount of time since a previous data transfer. When the counter value equals or exceeds the threshold, the system transmits the data. In another implementation, the system tracks the amount of data read from a buffer. The system reduces the speed at which data is read when the amount of data read from the buffer exceeds a threshold.

Abstract: A hyper throughput packet transmission method for a wireless local area network operating in burst and protection mode is provided. A first CTS frame is sent, comprising an NAV to reserve the medium for a duration. Upon completion of the first CTS frame delivery, a plurality of data frames are delivered to the destination. Upon completion of the data frame delivery, a second CTS frame is sent to reserve the medium for another duration, such that the previous steps form a loop. Delivery of the data frames comprises, a data frame is delivered from the source to the destination, and after the data frame delivered, waiting for an ACK frame from the destination within one SIFS interval. Upon receipt of the ACK frame, if the following data frame is ready, the previous steps loop, otherwise the delivery is complete.

Abstract: A ‘smart’ sub-channel hopping control mechanism executes one or more sub-channel selection discriminators to enable the communications controller of a spectral reuse transceiver to delineate on which of a plurality sub-channels the spectral reuse transceiver may transmit, so as to substantially reduce the likelihood of triggering squelch circuits of silent radios of primary (licensed) channel users.

Abstract: A configurable buffer arbiter is provided that combines a time-slot based algorithm, a fairness-based algorithm, and a priority-based algorithm to meet the bandwidth and latency requirements of multiple channels needing access to a buffer memory. The channels have different static and dynamic characteristics. The static channel characteristics include aspects such as a required latency for access to the buffer memory, a required bandwidth to the buffer memory, a preferred latency or bandwidth to the buffer memory, the amount of data the channel can burst in each access to the buffer memory, and the ability for the channel to continuously burst its data to the buffer memory with or without any pauses. The dynamic characteristics include aspects such as whether a channel's FIFO is nearing full or empty, or whether one of the static characteristics has suddenly become more critical. Configuration of the arbiter algorithms exists to optimize the arbiter for both the static and dynamic channel characteristics.

Abstract: A wireless LAN system if formed by a base station, mobile stations and a controller. The controller receives a frame over wireless media, and a frame analyzer analyzes the received frame. A determination section determines whether or not the frame received at a predicted time based on the rule of frame for a service on a layer higher than a media access control layer is an intended frame based on results from the frame analyzer. A frame transmitter sends out a frame containing a field specifying the duration of the frame to be transmitted to a destination station that should be given the first priority to transmit on a wireless uplink and downlink, based on the determination that the frame received is not in conformity with the rule of frame.

Abstract: Methods and apparatus for routing mixed cast requests through a Clos-like network are disclosed. According to one aspect of the present invention, a method for processing a routing request within a network system includes computing costs associated with input links between a center stage and an input stage and computing costs associated with output links between the center stage and an output stage. The method also includes comparing the costs associated with the input links and the costs associated with the output links to identify a first input link, a first output link, and a second output link. The first output link is associated with a first center stage node and the second output link is associated with a second center stage node. The request is routed using the first input link, the first output link, and the second output link.

Abstract: A method provides differentiated quality of service (QoS) by providing adaptive updates to media access control (MAC) layer parameters on a distributed basis. The method includes calculating a failure probability for a transmission over the network, determining a target value for determining a contention window according to a mapped function of the failure probability, and altering the contention window according to a scaling function of the target value. The mapped function and the scaling can provide QoS differentiation. A wireless device ensures fairness in a wireless time slotted network and includes a network interface card (NIC), a network driver interface, a network monitor, a statistics engine, and an adaptive parameter engine for determining a target value for determining a contention window according to a mapped function of the one or more probabilities to enable an alteration of the contention window and provide new parameters for the MAC layer.

Abstract: Multiple comparators compare the enable and priority values for multiple inputs and select a winner from one of the inputs. Multiple comparator stages each include one or more of the comparators. Each comparator stage selects winners from the outputs of a preceding comparator stage. The overall winners are those inputs that are winners in each comparator stage. If there are multiple overall winners, a second arbitration is preformed to identify an ultimate winner.

Abstract: An initial ranging detection for an orthogonal frequency division multiple access (OFDMA) wireless communication system entails removing data sub-carriers from samples of an OFDMA signal in order to suppress inter-carrier interference (ICI) between the data sub-carriers and initial ranging sub-carriers, coherently summing the resulting samples to boost signal energy, and applying a sliding window FFT to the coherently summed samples for correlating each result of the sliding window FFT with each one of a set of predetermined codes. The suppression of ICI is done by removing the cyclic prefix, performing an FFT to transform to the frequency domain whereupon the initial ranging sub-carriers are zeroed. An IFFT is then performed to return to the time domain. The cyclic prefix is then added and the new samples are subtracted from the originally received samples. The resulting samples are free of ICI and can then be coherently summed to boost signal energy.

Abstract: A method is dedicated to communications management for a random access communications network, in which time intervals are broken down into access slots, and during each access slot, a network terminal can transmit an access request to the network associated with a message that it wants to transmit, and comprising at least one processing device that introduces a long time for transmission of an access request acknowledgement message. This method consists of periodically sending acknowledgement messages to terminals, each message comprising positive acknowledgement information associated with each authorized access slot. Thus, when a requesting terminal receives an acknowledgement message later than an access request transmitted during a given access slot, it can transmit the message associated with its access request.

Abstract: The present invention seeks to improve data exchange in a communications system that is especially standardized according to IEEE 802.11a. For this purpose, when the transmission medium, preferably an IEEE 802.11 system with a distributed coordination function (DCF) is accessed in a decentralized manner, pilot signals are transmitted from the transmitter to the recipients using a number of transmission modes and then an allocation table regarding the transmission modes is calculated by the recipient on the basis of the pilot symbols received. The recipient transmits the allocation table to the transmitter so that the subsequent data exchange can proceed on the basis of the allocation table. In the case of centralized access, preferably an IEEE 802.11 system with a point coordination function (PCF), data exchange is improved in that the subsequent data are adaptively modulated already when the allocation table is transmitted.

Abstract: A novel and useful media access control (MAC) protocol that is intended for use over noisy shared media channels. The MAC protocol provides layer 2 functionality over a network using a shared medium including a backoff mechanism for CSMA/CA channel access, link addressing that reduces the overhead of long MAC addresses, a flooding scheme having controlled exposure for broadcast transmissions, multicast transmissions using selective ACKs, implementation of traffic prioritization using an adaptive backoff scheme, a second layer repeater establishment process and multi-packet transport for short packets and fragmentation for long packet transport.

Abstract: In one embodiment of the present invention, a method includes establishing a communication link between a first link partner and a second link partner, causing the first link partner to transmit idle signals, and analyzing a desired channel of the communication link using the idle signals. As an example, the communication link may be an Ethernet link and the link may be maintained during the channel analysis so that system data transmissions may be resumed or initiated immediately after the analysis is completed.

Abstract: Each node in a communication system transmits and receives state variable signals indicating internal node states or timings. A single node may transmit two or more differently phased series of state variable signals. Neighboring nodes interact by adjusting the timing phase at which they transmit each series of state variable signals according to the timing of state variable signals transmitted in other series, and state variable signals received from other nodes. The nodes can thereby establish time slots in which they can transmit data without collisions, and different nodes can receive different total amounts of time slot width by transmitting different numbers of series of state variable signals.

Abstract: A method of and system for time-division-based channel collision collaboration in a wireless communication system including at least two Wireless Regional Area Networks (WRANs) with overlapping service areas that employ dynamic frequency hopping is provided. The method includes performing, by at least one Consumer Premise Equipment (CPE) located in an overlapping portion of service areas of at least two WRANs, spectrum sensing and feeding idle channel information back to respective Base Stations (BSs) of the at least two WRANs, broadcasting, by each of the at least two WRANs, a pre-occupation announcement message for a qualified idle channel, and determining, by a WRAN with the highest priority of the at least two WRANs, a time resource allocation for WRANs in a channel collision state of the at least two WRANs. The method addresses problems, such as a large delay and impaired wireless access due to an absence of an idle channel for adjacent WRANs, may be avoided, while the WRANs may maintain their QoSs.

Abstract: A wireless network (100) includes a plurality of first wireless stations (101) and a plurality of second wireless stations (102). The first wireless stations are adapted to receive a frame (202, 401), which includes a duration value (207, 403) identifying a contention period (203, 402). The first wireless devices are adapted not to communicate during the contention period. The second wireless stations are adapted to communicate during the contention period. A method of wireless communication is also described.

Abstract: One embodiment of the present invention provides a system that facilitates registration of remote nodes in an Ethernet passive optical network (EPON). The system includes a central node and at least one remote node, wherein a number of virtual remote nodes are coupled to a common physical remote node and transmit upstream data through a common transmitter within the common physical remote node. During an initial discovery cycle, the system receives a solicitation message from the central node at a remote node, wherein the solicitation message assigns a discovery slot in which an unregistered remote node may transmit a response message to the central node for registration. The system then transmits a response message from an unregistered remote node to register within the assigned discovery slot.

Abstract: An assembly, and an associated method, for an ad hoc network, such as an independent basic service set defined in an IEEE 802.11 protocol specification. A channel map is created and maintained at each mobile station of the ad hoc network. The channel map is populated with channel characteristic indicia of channel frequencies that might be available upon which to be used in the ad hoc network to effectuate communications between the mobile stations. Information related to the channel map created and maintained at each of the mobile stations is exchanged, and any of the mobile stations is selectable to form a DFS owner that defines the channel frequency to be used upon which to define a communication channel for communications in the network.