Nortel Networks Corporation

Bae Systems Information and Electronic Systems Integration Inc.

Avaya Inc.

Victor Firoiu

Xiaohui Zhang

Eric Haversat

Thomas O Holtey

Marty Borden

Scott B LaPrise

Ikjun Yeom

Delfin Y Montuno

James Aweya

Michel Ouellette

Mohnish Anumala

Bruce A Schofield

Franco Travostino

Indermohan S Monga

Zhonghui Yao

Gregory Edward Lund

Carl Keene

Soumendra Nanda

Brian T Decleene

Brian DeCleene

Richard Lacerte

May M Leung

Yang Guo

Charles Tao

Gregory Lauer

Xinzhuo Shen

A mobile infrastructure assisted ad-hoc network increases the number of nodes capable of being serviced by the network by selectively choosing those protocols for selected nodes which minimize overhead with the freed up bandwidth permitting an increase in the overall number of nodes serviceable by the ad-hoc network to as many as 1,000 nodes. In one embodiment node dynamicity is determining factor as to what protocol will be used.

Mobile infrastructure assisted ad-hoc network

A system and method for dynamically planning a network is presented. One method may begin by determining network parameters for connecting nodes to a network and decision variables associated with radios and/or nodes in the network. Constraints may be established to narrow possible values of the network parameters and/or the decision variables. The constraints may be based on one or more of: values associated with connecting a radio to a node in the network, values associated with connecting two nodes in the network together over a communication link, whether a node can connect to a GIG node and a flow balance in the GIG node. To find possible links in the network that are optimal, the method may minimize an equation based on the network parameters, constraints and decision variables to determine optimal communication links between pairs of nodes in the network, pairs of nodes and radios and/or pairs of radios.

Skypoint for mobile hotspots

A system and method for transmitting encoded data in a network is presented. The method begins with a source node of a network encoding a first generation of data using linearly-independent encoding vectors to produce an encoded first generation. Next, packets containing the encoded first generation are created. The packets are then transmitted over a subgraph of nodes with multiple paths to a destination node. A determination is made at a receiving node that an insufficient amount of packets of the encoded first generation have been received in order to decode the encoded first generation. A repair request is sent from the receiving node to nodes upstream to indicate a need for more packets of the encoded first generation without specifying a particular packet. In response to the repair request, at least one node upstream from the receiving node sends a packet with encoded first generation data.

Control over network coding for enhanced radio transport optimization

Multiplexed traffic in a system where the maximum rate of all inputs exceeds the maximum rate of the output is processed via a separate queue for each input, and at any given forwarding clock cycle the earliest enqueued packet is forwarded via the output. In the event of congestion, a proportionally equal number of packets are dropped from each queue, where proportional equality corresponds to the number of packets dropped per number of packets enqueued. One implementation associates a time-stamp with each enqueued packet to indicate the time of enqueing relative to other enqueued packets. At any given forwarding clock cycle, the packet with the earliest time-stamp is forwarded.

Traffic multiplexing using timestamping

A method and apparatus for securing an optical communication link includes the step of identifying a profile of the link by measuring, at the transmitter, optical back-reflections from optical pulses forwarded to a receiver. The profile is stored at the transmitter. Periodically during operation, such as during key exchange, more optical pulses are forwarded to the receiver, and the back reflections are collected as periodic profiles. The periodic profiles are compared against the stored profiles. Eavesdroppers, such as those who cut the fiber, tap the fiber, or implement a man in the middle attack, may be easily identified because the losses caused by their interference with the fiber will be evident in the periodic profiles.

Method and apparatus for securing fiber in an optical network

Packets are spread among a number of packet processors with load-balancing. The incoming packets are logically divided into a number of packet flows, where the number of packet flows is greater than the number of packet processors. Each packet flow is assigned to a particular packet processor. When a packet is received, the packet flow for the packet is determined, and the packet is queued for the packet processor associated with the flow based upon a predetermined queuing scheme. The mapping of packet flows to packet processors is not fixed, but rather is dynamically updated based upon the amount of data associated with each packet flow and each packet processor.

System, device and method for scheduling information processing with load-balancing

Various techniques for queue management based on random early detection (RED) are disclosed herein. In particular, a method for generating a drop probability for an incoming packet in a device having a queue to buffer packets between segments of a network is provided. The method comprises determining, upon receipt of an incoming packet, a size of the queue and determining an error based at least in part on a difference between the queue size and a threshold. The method further comprises determining a drop probability for the incoming packet based at least in part on the error and a constant gain factor. The constant gain factor may be based at least in part on a linearized second order dynamic model of the network.

Constant gain controller for active queue management

A Balanced Packet Transmit Opportunity (BPTO) mechanism allows balanced bandwidth traffic to be serviced while still maintaining the service levels desired for high priority traffic. The above embodiment achieved the result by distinguishing both queue types and slot style types, and performing selections differently depending upon the relative styles of the queues and slots. This arrangement provides a number of advantages. Because the selection method is fast and relatively simple to implement, a large number of queues may be integrated into the decision process while maintaining a desired output bandwidth. In addition, the selection process provides a flexibility, allowing multiple traffic shaping considerations to be modified during operations to support changing network requirements. In addition, the selection process provides a flexibility, allowing multiple traffic shaping considerations to be modified during operations to support changing network requirements.

Queue scheduling with priority and weight sharing

A feedback output queuing system, apparatus, and method controls the rate at which packets are forwarded from the ingress ports to a particular output queue over the switching/routing fabric based upon the level of congestion at the output queue. The output queue is monitored and the level of congestion at the output queue is determined based upon a predetermined congestion determination mechanism. An ingress forwarding scheme is determined based upon the level of congestion at the output queue. Information is forwarded from the ingress ports to the output queue based upon the ingress forwarding scheme.

Feedback output queuing system, apparatus, and method

A method, apparatus, and computer program product for modeling dynamics of a queue are disclosed. A queue law function can be used to determine a control function for use in a congestion control module in a network for dropping packets. A queue law function may be determined based upon traffic conditions in the network. First a quantity that is representative of the link utilization between first and second nodes is determined. If the link is fully utilized, a quantity that is representative of an average round transmission trip time for data to be sent from the first node to the second node and an acknowledgment to be received by the first node is calculated. The queue law function which is dependent on a data drop probability based upon the link utilization, the buffer size, and the average round trip transmission time is determined. From this queue law function, parameters for defining a control function can be derived. These parameters include the minimum buffer size and the maximum expected queue size during normal operation for the node.

Method and apparatus for queue modeling

A method, apparatus, and computer program product for determining a drop probability for use in a congestion control module located in a node in a network is disclosed. A weight value for determining a weighted moving average of a queue in a node is first systematically calculated. The weighted moving average is calculating and an average queue size for the node is determined based upon the weighted moving average. A control function associated with the congestion control module is evaluated using the average queue size to determine the drop probability. In a further embodiment, the control function is calculated based upon a queue function where the queue function is calculated based upon predetermined system parameters. Thus, when the congestion control module drops packets based upon the drop probability determined by the control function the queue will not oscillate.

Method and apparatus for queue management

A model is given for performance evaluation of IP computer networks that are dominated by congestion-controlled traffic. The model includes heterogeneous TCP flows, UDP flows, short-lived TCP flows, and TCP flows in a differentiated services network. The performance of large-scale networks is estimated where flows may encounter multiple congested links.

Performance evaluation and traffic engineering in IP networks

Modeling link throughput in IP networks

An apparatus and method of managing received packets to be transmitted from a network device stores the received packets on one of two different buffers. In particular, the received packets are one of a first type of data packet and a second type of packet. Each one of the first type is stored in a first buffer having a first drop function, while each one of the second type is stored in a second buffer having a second drop function. Each respective drop function specifies a packet drop rate as a function of the average number of packets in its respective buffer. The first drop function has a first average drop rate over a specified time interval, while the second drop function has a second average drop rate over the specified time interval. The first average drop rate and the second average drop rate have a predefined relationship. Accordingly, if the two drop rates do not comply with the predefined relationship, then at least one of the two average drop rates are modified.

Growing community of inventors

Westford, MA, United States of America

Victor Firoiu