250 results about "Network congestion control" patented technology

A codec detects congestion in a packet network and responds via a session control protocol to re-negotiate codec-type and / or parameters with the receiving codec to reduce bit rate for supporting a session. Once the connection and session are established, encoded packets start flowing between the two codecs. A control entity sends and receives network congestion control packets periodically in the session. The congestion control packets provide a "heartbeat" signal to the receiving codec. When the network is not congested, all "heartbeat" packets will be passed through the network As network congestion increases, routers within the network discard excess packets to prevent network failure. The codecs respond to the missing packets by slowing down the bit rate or proceeding to renegotiate a lower bit rate via the session control protocol. If there are no missing packets, the codecs detect if the session is operating at the highest bit rate, and if not, re-negotiate a higher bit rate.

Methods and apparatus are provided for controlling congestion in a network such as a fiber channel network. Techniques are provided for detecting congestion at a shared resource such as a network node. When a controller sends data to a shared resource, the delay between sending the data and receiving a credit is measured. If the delay is significant, it is assumed that the path towards the destination associated with the data is congested and subsequent traffic from the port associated with the data is blocked.

Methods and apparatus are provided for controlling congestion in a network such as a fibre channel network. Techniques are provided for characterizing traffic flow at a congested network node. The congested network node can generate various instructions such as quench messages to control traffic flow towards the congested network node. The quench messages can optionally include information about the characteristics of the congestion. The instructions are distributed to other nodes in the network. The other network nodes can interpret the instructions and control traffic flow towards the congested node.

A communication network node, such as a radio base station or base station controller in a wireless communication network, is configured to monitor and control ingress and egress data congestion. As such, node-based congestion monitoring provides a method of flow control between network nodes and, as such, for example, it may be used to control congestion on backhaul links between radio base stations and base station controllers, and on sidehaul links between base station controllers. In one embodiment, the node monitors egress and ingress data congestion conditions, and marks ingress data incoming to the node to indicate congestion. For example, if ingress data markings indicate ingress data congestion, the node can send signaling to initiate a reduction in the amount of data being sent to the node, e.g., a reduction in ingress data rates. If ingress data markings indicate egress data congestion, the node can reduce egress data rates.

The invention provides a congestion control scheme that is a delay based scheme that includes a scalable queue size and one-way queueing delay measurement to reduce network congestion. Queue size is managed by queue control, a scalable utility function, dynamic alpha tuning, and / or randomized alpha tuning. One-way queueing delay is accomplished by measuring backward queueing delay management using various methods of estimating the receiver clock period. Embodiments include estimating the receiver clock period using single sample and multiple sample periods. The system includes a method for detecting route change.

The invention herein described consists of a method to compute in a end-to-end fashion the sending rate of data, audio and video flows over a packet switching network such as the Internet Protocol Network. The sending rate is computed as a function of the data sent in the recent past and as a function of a probing function w(t) that is dynamically set by taking into account signals of network congestion and the network changing available bandwidth.

A packet network congestion control system using a biased packet discard policy includes a plurality of end points having codecs operating in a framework, e.g. ITU-T H.323 protocol to establish a communication session. The protocol enables the codecs to negotiate codec type and associated parameters. Once a connection and session are established, compressed voice and data packets start flowing between the two end points. A control entity supplies congestion control packets periodically. The control packets provide a "heartbeat" signal to the codec at the other end of the session. Each codec receiver uses the "heartbeat" signal as an indication of network congestion. As network congestion increases, routers within the network discard excess packets to prevent network failure. The network discards all packets classified as congestion control packets whenever a flow control mechanism detects congestion or a trend toward congestion. As packets are discarded, the end points renegotiate codec type and / or parameters to realize lower bit rates.

The present invention is a delay based model and in fact uses queueing delay as a congestion measure, providing advantages over prior art loss based systems. One advantage is that queueing delay can be more accurately estimated than loss probability. This is because packet losses in networks with large bandwidth-delay product are rare events under TCP Reno and its variants (probability on the order 10−7 or smaller), and because loss samples provide coarser information than queueing delay samples. Indeed, measurements of delay are noisy, just as those of loss probability. Thus, another advantage of the present invention is that each measurement of queueing delay provides multi-bit information while each measurement of packet loss (whether a packet is lost) provides only one bit of information for the filtering of noise. This makes it easier for an equation-based implementation to stabilize a network into a steady state with a target fairness and high utilization. In addition, the dynamics of queueing delay provides scaling with respect to network capacity. This helps maintain stability as a network scales up in capacity.

A method and system of congestion control in a network are provided. A required quality of service (QoS) parameter, such as a maximum allowable latency, for a packet received at a queue in the network, and a route cost metric, such as accumulated and estimated latency, are determined, and the packet is either discarded if the route cost metric exceeds the required QoS parameter, or a discard bias value is set for the packet. Also, if the required QoS parameter exceeds the route cost metric, the method includes determining whether a congestion condition exists in the network, and if the congestion condition exists, biasing the packet for discard based on its latency if the route cost metric for the packet exceeds a threshold. The network may be an IP network, and a network such as a mobile ad hoc network (MANET).

A system and method of bi-directional and unidirectional communications is provided. The system includes a first host capable of transmitting multiplexed data at a first data transfer rate. A second host is provided that is capable of receiving multiplexed data at a second data transfer rate. The system further includes a data throttle that limits the first data transfer rate to a throttle value that is less than or equal to the lesser one of the first data transfer rate and the second data transfer rate. The system is operable on a UDP transport layer and an IP network layer and may be implemented by API calls to a sockets layer.

A method and system of congestion control in a network are provided. A required quality of service (QoS) parameter, such as a maximum allowable latency, for a packet received at a queue in the network, and a route cost metric, such as accumulated and estimated latency, are determined, and the packet is either discarded if the route cost metric exceeds the required QoS parameter, or a discard bias value is set for the packet. Also, if the required QoS parameter exceeds the route cost metric, the method includes determining whether a congestion condition exists in the network, and if the congestion condition exists, biasing the packet for discard based on its latency if the route cost metric for the packet exceeds a threshold. The network may be an IP network, and a network such as a mobile ad hoc network (MANET).

Methods, systems and devices for network congestion control exploit the inherent burstiness of network traffic, using a wave-based characterization of network traffic and corresponding multiplexing methods and approaches.

In a data network congestion control in a virtualized environment is enforced in packet flows to and from virtual machines in a host. A hypervisor and network interface hardware in the host are trusted components. Enforcement comprises estimating congestion states in the data network attributable to respective packet flows, recognizing a new packet that belongs to one of the data packet flows, and using one or more of the trusted components and to make a determination based on the congestion states that the new packet belongs to a congestion-producing packet flow. A congestion-control policy is applied by one or more of the trusted components to the new packet responsively to the determination.

The invention provides a network congestion control method, a network congestion control device and a network congestion control system. The method comprises the following steps of: monitoring data traffic of all service nodes in a distributed network; when the monitored data traffic of one or more service nodes exceeds a preset congestion threshold value, sending load balancing instructions and routing tables of idle service nodes to all the service nodes; and sharing the data of the congestion service nodes by the idle service nodes according to the load balancing instructions. By sharing the data of the congestion service nodes to the idle service nodes to balance the load of the congestion service nodes, congestion control of an application layer is realized, the congestion control efficiency is improved, meanwhile, the defect of data loss of the application layer in the prior art is avoided, the data integrity is improved, and the stability of each service system in the distributed network is further improved.

A method and apparatus for congestion control for acknowledged communication over networks detects congestion based on trends of flight size and transmission rate in order to adapt a congestion window in accordance with a detection result. Such congestion detection enables, for example, distinguishing between the congestion with or without unfair competition. Moreover, the measured transmission rate or its trend can be filtered to compensate for time variations. An end node or a proxy can be used for congestion control.

The invention relates to a pervasive service-oriented adaptive network congestion control method. The method comprises the following steps that: a source node for transmitting information measures round-trip time (RTT) of a target node for receiving the information, wherein when the ratio CSRTT of the latest measuring value to the minimum of the historical RTT is increased, the congestion is caused by too many packets forming a line in an intermediate network node; the target node distinguishes the received data packet is a normal data packet or is a packet-pair used for detecting bandwidth and feeds the estimated available bandwidth back to the source node; according to a feedback signal, the source node distinguishes the congestion states with four levels according to a preset rule and uses the four congestion states as a basis of speed adjustment; when a new connection exists, the target node transmits three repeated acknowledge characters (ACK) of the last received data before switching; and the source node resets a slow start threshold by using the result after receiving an acknowledgment packet which is not data bursting one window, but data for only transmitting two back-to-back packets to detect the available bandwidth on a new path.

A codec detects congestion in a packet network and responds via a session control protocol to re-negotiate codec-type and / or parameters with the receiving codec to reduce bit rate for supporting a session. Once the connection and session are established, encoded packets start flowing between the two codecs. A control entity sends and receives network congestion control packets periodically in the session. The congestion control packets provide a “heartbeat” signal to the receiving codec. When the network is not congested, all “heartbeat” packets will be passed through the network As network congestion increases, routers within the network discard excess packets to prevent network failure. The codecs respond to the missing packets by slowing down the bit rate or proceeding to renegotiate a lower bit rate via the session control protocol. If there are no missing packets, the codecs detect if the session is operating at the highest bit rate, and if not, re-negotiate a higher bit rate.

The invention pertains to methods and apparatus for determining when and how to perform communications network congestion control tactics, such as reconfiguring pipeline bandwidths, with respect to packet-based networks.

The invention claims a software-defined network congestion control algorithm based on stream segmentation and belongs to the technical field of communication networks. First, an SDN (software-defined network) controller initializes network topology and forwarding paths; the controller monitors traffic of all links by transmitting State-Request information periodically to a switch to query states of the switch and its ports, and then calculates load condition of each path; when the load of one path is greater than a set congestion threshold, a large stream on the path may be split into a plurality of sub-streams, and the controller schedules the sub-streams to the other available paths with light load by issuing corresponding stream tables; the controller queries the state of the switch periodically, and transmits a message of decreasing data packet rate to a source switch when usage of a cache of a target switch is excessive; the algorithm performs path reselection on data streams leading to link congestion and re-ranks data packets, transmitting rate of a source port is reduced, and load of a link with high load is relieved and network congestion is relieved.

A method in a communication network includes defining a root congestion condition for a network switch if the switch creates congestion in the network while switches downstream are congestion free, and a victim congestion condition if the switch creates the congestion as a result of one or more other congested switches downstream. A buffer fill level in a first switch, created by network traffic, is monitored. A binary notification is received from a second switch, which is connected to the first switch. A decision whether the first switch or the second switch is in a root or a victim congestion condition is made, based on both the buffer fill level and the binary notification. A network congestion control procedure is applied based on the decided congestion condition.

A codec detects congestion in a packet network and responds via a session control protocol to re-negotiate codec-type and / or parameters with the receiving codec to reduce bit rate for supporting a session. Once the connection and session are established, encoded packets start flowing between the two codecs. A control entity sends and receives network congestion control packets periodically in the session. The congestion control packets provide a “heartbeat” signal to the receiving codec. When the network is not congested, all “heartbeat” packets will be passed through the network. As network congestion increases, routers within the network discard excess packets to prevent network failure. The codecs respond to the missing packets by slowing down the bit rate or proceeding to renegotiate a lower bit rate via the session control protocol. If there are no missing packets, the codecs detect if the session is operating at the highest bit rate, and if not, re-negotiate a higher bit rate.

A method and apparatus are provided for bandwidth management. The method includes receiving a value representative of a target bandwidth from a remote device; storing a data packet in a data queue; associating a quantum of bandwidth to the data queue, wherein the quantum of the bandwidth is a function of at least the target bandwidth and time; and transmitting the data packet based on at least the quantum associated with the data queue. A method and apparatus for network congestion control are also provided.

The invention discloses an SDN data center network congestion control method based on rerouting. The method comprises the following implementation steps: a data center network topology is perceived; aflow statistics request message is sent, and a statistics amount is acquired; by utilizing a flow rate calculation formula, the rate of each flow is calculated; an initial path of each flow is determined; a size relation between a link load of the large flow and a link congestion threshold value is compared, and the congested large flow is detected; a rerouting path is calculated for the congested large flow; and a flow entry is installed on each switch in the rerouting path. According to the method, the characteristics of the data center network flows are considered, and only the large flowis re-routed, so that the time delay of the small flow is shortened; and the utilization rate of the path and the key degree of the path are considered jointly, and the rerouting path is distributed to the congested large flow, so that the congestion of a data center network is relieved.

The invention discloses an RED-based network congestion control algorithm. The algorithm comprises the following steps of: segmentally processing different congestion states by introducing a fifth-order classification method in the statistics, dividing the network congestion states by using five indexes of weak, slight, medium, serious and severe, and dividing the average queue utilization rate into five regions, each of which corresponds to a network congestion state; calculating the discard probability of the average data size of the regions by utilizing a liner function of a data size distribution probability; and discarding data packets in corresponding regions in the probability according to the current congestion state to increase the available space of queues so as to avoid the network congestion. In the algorithm, original ten configuration parameter projects of the conventional algorithm are reduced to two, so that the configuration difficulty is obviously reduced. Under the same network scene, the average queue cache utilization rate is about 25 percent higher than that of an RED derivative algorithm. The algorithm improves the network congestion control effect, can flexibly adjust the packet loss number according to the congestion degree, and effectively inhibit network jitter.

The invention discloses a service network congestion control method, comprising: in the process of service message interaction between a local device and a peer device, sensing the link congestion status; starting or closing the flow control according to the link congestion status; , discard the first message of the service sent to the peer device. The invention also discloses a service network congestion control device, which includes: a congestion sensing unit, a flow control control unit, and a flow control execution unit. The invention can realize the automatic flow control of wireless link congestion and reduce the impact on business.

The invention discloses a network congestion control method and equipment. The method comprises the following step: user equipment confirms that the random access process is initiated according to information for expressing whether treatment is carried out or not on the basis of a network congestion message; or the user equipment confirms that the network congestion message is read according to the information for expressing whether the treatment is carried out or not on the basis of network congestion message and confirms that the random access process is initiated or not according to a reading result of the network congestion message. In the embodiment of the invention, the congestion caused by randomly accessing a plurality of MTC (Machine Type Communication) terminals into a network is prevented; after the network congestion is generated, the network congestion condition can be improved by reducing or prohibiting MTC terminal access, and the influence on the traditional user equipment access by the MTC terminal access is reduced.

Methods and apparatus are provided for controlling congestion in a network such as a fibre channel network. Techniques are provided for characterizing traffic flow at a congested network node. The congested network node can generate various instructions such as quench messages to control traffic flow towards the congested network node. The quench messages can optionally include information about the characteristics of the congestion. The instructions are distributed to other nodes in the network. The other network nodes can interpret the instructions and control traffic flow towards the congested node.