Abstract: A packet transmission apparatus transfers arriving packets directly to a highest-priority queue under non-congestion conditions, and classifies the priority of a packet only on the existence of congestion. In one embodiment, non-congestion is determined when all queues are empty. In another embodiment, congestion or non-congestion is determined by upper and lower thresholds on the total number of packets in all queues. The ability to omit classifying incoming packets in the non-congestion condition improves processing speed, and eliminates the need for re-queuing or packet-replacing operations.

Abstract: Network channel access protocol is disclosed. More particularly, a distributed, locally determined, channel access protocol that adapts to load, avoids interference and controls access by a group of nodes to a set of shared channels is disclosed. Shared channel space is divided into a number of communication slots that are repeated at a predetermined interval. Permission to use a slot to communicate between any two nodes is dynamically adjusted by the channel access protocol, which locally: (i) estimates load to neighboring nodes; (ii) allocates or deallocates slot usage to adapt to load and avoid interference; and (iii) asserts and advertises slot usage within an interference area about itself.

Abstract: A content addressable memory includes a priority encoder that is in communication with an array of the content addressable memory cells to receive match signals, and from the match signals generating an output index signal in accordance with a priority sequence of the match signals. The priority encoder has a plurality of input circuits to receive the match signals from the CAM array. A priority setting circuit receives a priority transformation signal indicating a priority index for modification of the priority sequence. An encoding circuit is in communication with the plurality of input circuits and the priority setting circuit for generating the output index signal in accordance with the priority sequence. The priority encoder circuit further includes an enabling circuit for receiving an enabling signal.

Abstract: In a real-time distributed control system in which a plurality of network controllers are connected, a middleware module in each control unit executes starting of application modules and calling RT communication processing according to starting order information in application configuration information. RT communication service sends and receives messages between the application modules corresponding to the calling. The application configuration information and the messages are generated by an information processor based on user defined information, and transmitted to each of the units. A network driver executes network communication using a network controller which stores sending and receiving messages. A network driver priority manager determines priority of processing of the network driver corresponding to priorities of sent and received messages, and a scheduler executes processing of the network driver according to the priority of the processing of the network driver.

Abstract: A scheduler, scheduling method, and computer program product are provided for implementing Quality-of-Service (QoS) scheduling of a plurality of flows with aging time stamps. Subsets of time stamp data stored in a time stamp aging memory array are sequentially accessed. Each time stamp data subset contains time stamp data for a subplurality of flows. Guaranteed aging processing steps are performed for each flow utilizing the time stamp data subsets to identify and mark invalid calendar next time values. When a new frame arrival for an empty flow is identified, flow queue control block (FQCB) time stamp data and the flow time stamp data in the time stamp aging memory array are accessed. Based on the calendar to which the new frame is directed or the target calendar for the new frame, the target calendar next time valid bit of the time stamp aging memory array data is checked.

Abstract: Method (130) for optimizing emergency call service in a Virtual Local Area Network including at least one Voice over Internet Protocol device. A range of port numbers is reserved for use during emergencies (134). Next, a VoIP device transmits an emergency call within the VLAN using a port in the specified range (136). Extra resources are reserved for handling the calls using ports within the specified range (138).

Abstract: Systems and methods implement a high speed wireless network. The systems and methods include using multiple channels of a wireless network interface to send and receive data simultaneously. Aspects of the system and methods include load balancing, error correction, and link aggregation over the multiple wireless channels.

Abstract: A system and method of providing flexible QoS actions through communication to neighboring network elements of the local QoS actions taken by the local network element. The neighboring network elements may then take into account the QoS actions taken by the local network element when the neighboring network elements are contemplating their own QoS actions to be taken. Thus, a limited range of visibility of QoS actions facilitates subsequent QoS actions taken by the network elements within the limited range of visibility.

Abstract: An approach for scheduling packets within a terminal used in a satellite communications system is disclosed. A hub, in conjunction with a satellite, controls bandwidth allocations to a plurality of terminals, which are configured to issue bandwidth allocation requests to the satellite. Each of the terminals comprises a plurality of queues that are configured to store the packets; these queues are prioritized. A bandwidth-on-demand control logic prepares a schedule plan for transmitting the stored packets based upon current bandwidth allocations and the prioritization of the queues. The current bandwidth allocations are based upon prior bandwidth allocation and the stored packets. The schedule plan assigns the stored packets to packet transmission opportunities associated with the current bandwidth allocations.

Abstract: Several techniques are provided for use by wireless devices to avoid interference with signals that are of a periodic or quasi-periodic nature that may operate in the same frequency band and proximity. In some cases, the periodic signals are detected and their timing is determined so as to predict when a next interfering event will occur. Devices that are affected by the periodic signal (such as an affected device with information to be transmitted or devices that have information to be transmitted to the affected device) are controlled to prevent transmissions during the interfering intervals. In addition, a process is provided to dynamically fragment a transmit frame of information to transmit part of the information before the interfering interval and the remainder of the information after the interfering interval, rather than waiting to transmit the entire frame until after the interfering interval.

Abstract: The invention relates to a communications system and a method for establishing a broadband connection, for example a multi-media connection between two or more users, by means of exchanges in a communications network, for example an ATM network. According to the invention, when the exchanges receive a request from a calling user to establish a broadband connection, said exchanges first establish a minimal connection between the users and once the minimal connection is in operation between the users, the requested broadband connection is established. The users of broadband network capacities, which have been reserved by the network at the request of the user, are billed during the call phase. Broadband connections of this type can receive a higher priority than the upgrade of minimal connections to complete connections. A voice connection comprising audio data constitutes for example a minimal connection. The broadband connection takes place for example between video telephones.

Abstract: A method and system for implementing weighted fair flow control on a metropolitan area network. Weighted fair flow control is implemented using a plurality of metro packet switches (MPS), each including a respective plurality of virtual queues and a respective plurality of per flow queues. Each MPS accepts data from a respective plurality of local input flows. Each local input flow has a respective quality of service (QoS) associated therewith. The data of the local input flows are queued using the per flow queues, with each input flow having its respective per flow queue. Each virtual queue maintains a track of the flow rate of its respective local input flow. Data is transmitted from the local input flows of each MPS across a communications channel of the network and the bandwidth of the communications channel is allocated in accordance with the QoS of each local input flow. The QoS is used to determine the rate of transmission of the local input flow from the per flow queue to the communications channel.

Abstract: The utilization of an non-QOS guaranteed network is envisioned within a communication network to increase bandwidth when necessary. In this system two locations are connected by two separate communications networks one QOS guaranteed QOS guaranteed network while the other non-QOS guaranteed packet based network without QOS guarantee. A smart buffering system integrates the two networks.

Abstract: A method and system for providing priority to a station in a congested half duplex Ethernet network. Specifically, one embodiment of the present invention includes a method for providing priority to a peripheral component (e.g., half duplex Network Interface Card) in a congested network. The method includes the step of detecting a collision of a data packet during transmission of the data packet by a peripheral component coupled to a network. Furthermore, the method includes the step of determining a restricted back off time. It should be appreciated that the restricted back off time is substantially equal to or less than a restricted time value. Additionally, the method includes the step of causing the peripheral component to wait the restricted back off time before trying to retransmit the data packet over the network.

Abstract: The present packet scheduling algorithm gives cellular network operators greater flexibility in adjusting the way resources are allocated among interactive best-effort data users. Best effort data users with different radio link qualities may have different amounts of data delivered to them using the same amount of radio resource. In the context of link adaptation, this characteristic complicates the fairness issue in cellular environments and has a profound impact on the overall system performance. As a result, the present packet scheduling algorithm is capable of allocating radio resource dynamically, not only based on channel conditions, but also to achieve different performance trade-offs among users with different link qualities. According to the algorithm, channel quality is determined for each user, channel efficiency is calculated and the channel efficiency value is used as the primary factor in weighting the delivery of packets to (or from) a given user.

Abstract: There is provided a packet scheduler for managing output awaiting packets stored in a plural of queue blocks each having a weighting coefficient settled based on an output guaranteeing bandwidth, whereby an output order for the head packets is stored in respective queue blocks. The packet scheduler includes means for controlling selection of a queue having a packet to be sent at the highest priority, based on scheduled output time information obtained by calculation using management information of the output awaiting packets and the weighting coefficient of each queue, and means for correcting processing carried out in the controlling means based on the current time information. The arrangement enables to ensure assignment of vacant bandwidth in a fair manner while suppressing erroneous operation deriving from deviation of a scheduled packet output time from the real time caused by a calculation error or the like in WFQ calculation.

Abstract: Opportunities to transmit ATM cells of identical level onto an ATM line are equally afforded to respective terminal side lines. In a cell assembler/disassembler, data from the terminal side lines 1100 are turned into ATM cells, and the ATM cells are assigned priority levels. Then, the ATM cells are stored in internal buffers 111–116 respectively corresponding to the terminal side lines 1100. The priority controller 1210 selects the ATM cells of the highest priority levels from within the respective internal buffers, and further selects the ATM cell of the highest priority level as an ATM cell to-be-transmitted from among the selected ATM cells. In the presence of a plurality of such ATM cells of the highest priority level, the priority controller 1210 determines the ATM cell to-be-transmitted in accordance with the priority sequence of the internal buffers in which the ATM cells of the highest priority level are stored.

Abstract: A method for generating ATM cells for low bit rate applications, said method including a step of scheduling ATM cell transmission times in a way as to keep ATM cell spacing as constant as possible, and a step of multiplexing a plurality of low bit rate connections into a same ATM connection having the thus scheduled ATM cell transmission times.

Abstract: The present invention focuses on the aggregation of flows belonging to different classes of non-guaranteed-delay traffic into a single FIFO queue in a downstream stage of the multi-stage switch. These include the guaranteed flows requiring bandwidth reservation, the best-effort flows that require a fair share of the excess bandwidth, and the flows that require both types of guarantee. We disclose a credit-based backpressure scheme which selectively controls the traffic originating from the previous stage of the system while achieving the goal of meeting the requirements of the individual flows. The credit function is maintained for each controlled traffic component in the aggregate session, and its objective is to balance the actual arrival rate of the component with the service rate dynamically granted by the downstream scheduler. The number of flows that can be aggregated is related to the complexity of maintaining the credit functions for the different traffic components.

Abstract: In a method of fair queue servicing at a queuing point in a multi-service class packet switched network, incoming packets are received in buffers and outgoing packets are scheduled by a weighted fair queue scheduler. Real-time information of buffer usage along with the minimum bandwidth requirement is used to dynamically modify the weights of the weighted fair queue scheduler.

Abstract: A common part sublayer (CPS) ATM adaptation device provides an interface between a narrow band network and a broad band network. The adaptation device is functionally partitioned to provide scheduling, prioritization and multiplexing of ingress traffic to the broadband network independently of the adaptation layer (AAL) type of that traffic. The device incorporating ingress and egress paths respectively to and from the broadband network. The egress path provides segregation and delineation of incoming data units on to respective external data ports, and the ingress path incorporates a common memory for payload storage whereby to perform multiplexing at both AAL and ATM layers.

Abstract: A method and apparatus for scheduling upstream data packets in a communication system is described. The present inventive method obtains a priority value (PV) for an upstream data packet and compares (using hardware registers) the PV of a queued upstream data packet to a current system timer. In accordance with one embodiment of the present invention, the current system timer comprises the current clock time of the communication system. When a PV equals the current system timer, the method transmits the upstream data packet associated with the PV to the CMTS via the upstream transmission path.

Abstract: In a telecommunication switching arrangement where data packets have multi-level indices associated with the loss and delay aspects of the data packet, a mathematical operation on the indices allows the switching arrangement to assign data packets to groups. The sequence in which the data packets are transmitted by the switching arrangement is based on the group to which the data packet belongs. This effectively results in a relative prioritization of the data packets. Additionally, the loss and delay indices determine storage priority and relative priority inside a group. The switching arrangement achieves low loss and low delay for the data packets to be transmitted.

Abstract: A distributed arbiter prioritizes requests for resources based on the number of requests made by each requester. Each resource gives the highest priority to servicing requests made by the requester that has made the fewest number of requests. That is, the requester with the fewest requests (least number of choices) is chosen first. Resources may be scheduled sequentially or in parallel. If a requester receives multiple grants from resources, the requester may select a grant based on resource priority, which is inversely related to the number of requests received by a granting resource. In order to prevent starvation, a round robin scheme may be used to allocate a resource to a requester, prior to issuing grants based on requester priority.

Abstract: The invention relates, in one embodiment, a computer-implemented method for shaping the output of cells on an output path of a data transmitting device. The data transmitting device is configured for switching the cells from a plurality of input paths to the output path to a network. In one embodiment the method includes sorting a plurality of queues, each queue including a plurality of cells associated with a communication device. The plurality of queues are arranged according to a weight and a data rate associated with each plurality of cells resulting in a plurality of sorted queues of queues. An aggregate output of cells from each sorted queue of queues is regulated based upon the data rates of the queues of the each sorted queue of queues. And, the output of the aggregate output of cells from each sorted queue of queues is regulated based upon the weights of the each sorted queue of queues, such that the scheduled output is coupled to the output path.

Abstract: A method of carrying out arbitration in a packet exchanger including an input buffer temporarily storing a packet having arrived at an input port, and a packet switch which switches a packet between a specific input port and a specific output port, includes the steps of (a) concurrently carrying out a first plurality of sequences in each of the sequences basic processes for at least one of the input buffer and the output port are carried out in a predetermined order, and (b) making an allowance in each of the sequences for packets to be output through output ports at different times from one another.

Abstract: Uplinked and downlinked transmissions in an interference-limited system, such as a cellular network, are prioritized and authorized by channel quality/data rate to minimize interference.

Abstract: An L bit for notifying another router of whether a self-router belongs to a connection-oriented network is newly provided in the options field of a conventional OSPF packet and the OSPF packet, including L bit is transmitted to another router. In this way, each router belonging a network can automatically recognize a router belonging to a connection-oriented network by detecting L bit. Then, by generating a routing tree, a connection-oriented network device can be identified in the routing tree and mapping between a connection-oriented network and a connectionless network can be performed in an edge device.

Abstract: A method and apparatus is described for receiving a new policy tree at a network element in a network. The network element stores a current policy tree of classes for quality of service of packets being processed by the network element. Classes of the current policy tree are compared with the classes of the new policy tree. Classes of the current policy tree are selectively deleted and classes of the new policy tree are selectively added to the current policy tree based on the comparison of the classes.

Abstract: A method of adaptive resource allocation in transmitting data is provided. In particular, the method of the present invention is applicable to scheduling bandwidths using a modified and dynamic weighted round robin process. The method includes the steps of allocating a resource to each of a plurality of data transmitting active connections, the plurality of active connections belonging to more than one class of service. Then the method determines a lender class of service for each active connection from which resources may be reallocated to the active connection, and periodically comparing the resource usage of an active connection to an upper threshold and a lower threshold.

Abstract: A method of, and means for accomplishing the method, optimizing system resources in a network (102) using packetized voice telephony consists of the following steps: determining (302) that a packetized voice call from an originating gateway (104) terminates at a non-human voice interface system (108), wherein the packetized voice call is assigned a specified high priority level; and transmitting (304) signaling to cause the originating gateway (104) to transmit the packetized voice call to the non-human voice interface system (108) at a lower priority than the specified high priority level.

Abstract: A system and method for data flow classification based on a configurable rule-engine, is presented herein. In accordance with an embodiment of the invention, the system includes a data flow managing mechanism configured to identify, track, and manage the data flows and a rule set, which includes a plurality of rules for comparing information contained within data flow with pre-specified values. The system also includes a configurable classification rule engine for classifying the data flows into one of a plurality of traffic classes based on results of the comparisons. The configurable classification rule engine is configured via a configuration file that specifies and allows for the modification and reconfiguration of the pre-specified values and information regarding the data flows, the rule set, and the traffic classes.

Abstract: A method and apparatus for controlling the admission of data packets into a network element is described. In an embodiment, a method for controlling admittance of a data packet into a memory buffer includes performing, prior to queuing the data packet for routing by a processor, the following: (1) receiving a data packet from one of at least two different ports, (2) determining a priority value within the data packet, and (3) determining an admittance group identifier for the data packet based on the priority value and the port the data packet was received. The method also comprises queuing the data packet from the memory buffer to one of a number of queues for routing by the processor upon determining that a number of data packets stored in the memory buffer and having the admittance group identifier is not greater than a threshold value.

Abstract: A method and system for sharing over-allocated bandwidth between different classes of service in a wireless network. Traffic is transmitted for a first service class in excess of bandwidth allocated to the first service class using unused bandwidth allocated to a second class. After transmitting traffic for the first service class in excess of bandwidth allocated to the first service class using unused bandwidth allocated to a second class, traffic for a third service class is transmitted in unused bandwidth remaining in the second service class.

Abstract: A packet communication system of the present invention has first mode, second mode and third mode to apply to input packets. The first mode is a mode that decides priority of the packet by at least one of the address information and the application information, the second mode is a mode that decides priority of the packet by the DS value, the third mode is a mode that decides rewrite the DS value by at least one of the address information and the application information. A control unit of the packet communication system switches a mode to apply an input packet of the first mode, the second mode and the third mode based on the packet header information of the input packet.

Abstract: A packet switching apparatus for simplifying and reducing the size of a packet switching circuit which is to perform at high speed. The packet switching apparatus is provided with a first packet switching unit for sorting a data packet from one of a plurality of input lines into one of a plurality of transfer lines. The packet switching apparatus is also provided with a second packet switching unit for sorting a data packet from a transfer line into one of a plurality of output lines of a respective output line group. A transfer line transfers a data packet at a line speed faster than a sum of the line speeds of the output lines included within the respective output line group.

Abstract: A circuit size of a multiplexing apparatus is reduced. In terminal interface units 21a to 23a, data from a terminal is received by each of terminal-side line interface sub-unit 211, and then celluralized by a cell assembly/disassembly sub-unit 28a. The cell is transmitted directly to a priority control unit 242a. In the priority control unit 242a, the cell received from each of the terminal interface units 21a to 23a is stored in each of priority control buffers 243a, and then sent to an ATM network interface unit 24a in the order of priorities sequentially. The cell is synchronized with a line of an ATM network 1a by a network synchronizing sub-unit 241a, and transmitted to the line of the ATM network 1a. With this constitution, an internal bus is unnecessary.

Abstract: A method and apparatus includes identifying an address portion of a first message in an address slice of a switch, the first message associated with a first priority, the address portion of the first message including a first routing portion specifying a network resource; identifying an address portion of a second message in the address slice, the second message associated with a second priority, the address portion of the second message including a second routing portion specifying the same network resource; identifying a non-address portion of the first message in a non-address slice of the switch; identifying a non-address portion of the second message in the non-address slice, wherein neither of the non-address portions includes a routing portion specifying the network resource; selecting, independently in each slice, the same one of the first and second messages based on the first and second priorities; transferring the address portion of the selected message to the network resource specified by the rout

Abstract: A multiport network device includes output port logic, priority logic, a memory, and memory logic. The output port logic generates output port data that identifies output ports to transmit received packets. The priority logic generates priority data that identifies priorities of the received packets. The memory stores the output port data from the output port logic and the priority data from the priority logic. The memory logic receives priority data relating to one of the received packets from the output port logic, determines whether the memory stores output port data relating to the packet, ignores the received priority data when the memory stores no output port data relating to the packet, and when the memory stores output port data relating to the packet, transmits the received priority data and the stored output port data to the identified output port.

Abstract: Providing packet-based service differentiation on packet-based networks involves first determining information associated with packets as a basis for inferring connection characteristics associated with the respective packet, as the packets pass though a particular network node. Statistical measures based on numerical values of, for example, Round Trip Time (RTT), is used to characterize connections as being, in this case “long” or “short”. “Long” connections are given a higher priority than “short” connections. Accordingly, the assigned priority associated with particular packets can be used to adjust drop probabilities for those packets.

Abstract: A method and apparatus are provided for scheduling data for transmission over a communication link shared by multiple applications operating on a host computer. The apparatus incorporates multiple storage components, with each storage component configured to store descriptors of data having one of multiple priorities. Each descriptor identifies a location (e.g., in host computer memory) of a portion of data to be included in a packet transmitted over the communication link. The apparatus services each storage component in turn to retrieve one or more descriptors, identify their associated data, retrieve the data and prepare it for transmission. Each storage component has an associated weight, which may be proportional to the priority of data represented by descriptors stored in the component. A storage component's weight may indicate a portion of the transmission bandwidth or a maximum amount of data that may be scheduled for transmission each time the component is serviced.

Abstract: A network device that controls the communication of data frames between stations includes a memory that stores frame pointers that point to addresses in an external memory. The data frames are stored in the external memory while the network device generates frame forwarding information for the respective data frames. The network device divides the available frame pointers into a number of categories corresponding to priorities associated with the data frames. When a frame is received at the network device, frame processing logic determines the priority of the data frame and checks whether a frame pointer corresponding to that particular priority is available. If no frame pointer corresponding to that priority is available, the multiport switch drops the data frame.

Abstract: An apparatus and method for DBWRR (Delay Bound Weighted Round Robin) cell scheduling in an ATM (Asynchronous Transfer Mode) switch. More particularly, the present invention provides an apparatus and method for DBWRR cell scheduling in a high-speed ATM switch which can meet requirements for a cell transfer delay of real-time traffic in the ATM switch and minimize a processing overhead of the switch.

Abstract: A method and apparatus for selectively accelerating network communications provides improved operation of network communications through channels with long delays, such as a satellite communications channel. A configuration management mechanism provides a selection of acceleration configuration for particular addresses of devices that may communicate through the communications channels. Acceleration may be bypassed for particular addresses or classes of devices within the network and priorities may be assigned, permitting a cut-off of acceleration when a threshold number of sessions is reached. The method and system may also allow a higher priority class of session to preempt lower priority session by removing resources from the lower priority session and assigning them to the higher priority session. The data rate of the lower priority session is then lowered (due to the absence of acceleration or reduced buffer size) to reduce traffic flow.

Abstract: A packet transfer device that can be easily realized even when a number of input ports is large. Each input buffer temporarily stores entered packets class by class, and outputs packets of a selected class specified by the control unit, while the control unit determines the selected class of packets to be outputted from the input buffers according to a packet storage state in the packet storage units of the input buffers as a whole for each class. Each input buffer can temporarily store entered packets while selecting packets to be outputted at a next phase, and the control unit can specify packets to be selected in the input buffers according to an output state of packets previously selected in the input buffers as a whole. Packets stored in the buffer can be managed in terms of a plurality of groups, and each packet entered at the buffer can be distributed into a plurality of groups so that packets are distributed fairly among flows.

Abstract: Embodiments of the present invention relate to generating a bundle of data (e.g. a packet). The bundle of data may comprise cells from a first queue and a second queue. All of the cells in the first queue are each independent. At least two cells of the second queue are dependent.

Abstract: A method for identifying and choosing a shortest path segment that has an alternate edge disjoint path segment. While routing Unidirectional Path Switched Ring (UPSR) path segments in a graph, there may be several equal distance paths to choose the shortest path from. Choosing a certain path as the shortest path may minimize or eliminate the chance of finding an alternative path segment. A method is provided such that if multiple shortest paths from the source node to a particular destination node exist, the method selects the shortest path which has an alternate edge disjoint path, and which can be used for path protection. The particular shortest path chosen by the method is not necessarily the first shortest path constructed.

Abstract: A method, comprising the steps of appending a data packet to a data stream queue (“DSQ”), the DSQ having a priority level, allocating a quantum of bandwidth to the DSQ and transmitting the data packet as a function of the priority level and the quantum of bandwidth.

Abstract: A method for class-based per-flow queuing for use with multiple link-sharing hierarchies, where each one of multiple link-sharing hierarchies imposes a different resource allocation program at one or more levels of differentiation, extending from the link root node to each individual data flow. A new queuing decision layer is introduced that considers all hierarchies simultaneously and arrives at a single queuing solution.

Abstract: Systems and method for switching packets of information between ports are provided. One system comprises a plurality of port processors, a switch fabric and a scheduler. The port processors send packet headers to the scheduler, which resolves contentions between packet headers with the same destination port addresses. The scheduler sends request-grant information to the port processors. The port processors send packets as specified by the request-grant information to the switch fabric. The switch fabric transfers the packets between the port processors according to the destination port addresses of the packets.