82 results about "One-way delay" patented technology

Methods and apparatuses are provided for user equipment positioning in networks. An example method includes computing a location of a user equipment (UE). The computing includes joint scheduling of UL subframes and receiving a Up Link Positioning Reference Signal (UL-PRS). The computing is performed by a network equipment that serves at least one cell site. The UL-PRS is received in a known subframe. The computing may also include estimating an arrival time the UL-PRS from the UE for a plurality of cell sites. In another embodiment, the computing includes determining a one-way delay between

Measurement systems according to embodiments of the invention allow accurate bandwidth estimation even in non-FIFO scheduling and frame-level contention environments. In an embodiment of the invention, the approximate fraction of time that a link is idle is found by probing for idle periods (“gaps”). The fraction of idle time is then multiplied by the capacity to obtain an estimate of the available bandwidth. Gap time is estimated in an embodiment of the invention fraction by gathering samples of one-way delay (OWD) over the link in question. After the OWD is normalized and plotted, the knee in the cumulative distribution function (CDF) of OWD samples is used to identify the fraction of time that the channel is idle.

In one implementation, data is communicated along a communications route in a network. A mediatrace request is generated for the communications route. Responses to the mediatrace request are received from along the communications route. The hop-by-hop latency is passively measured, from the responses, with one-way delay along the communications route in the network.

A communication terminal which sets a communication session between a plurality of communication terminals through a network to perform data transmission and reception includes a measuring unit which measures round-trip delay time (RTT) or one-way delay time between the communication terminals for performing transmission and reception on the basis of the received acknowledgement, a reception bandwidth measuring unit which measures a reception bandwidth in a reception terminal of the communication terminals on the basis of the received acknowledgement, a correcting unit which corrects a value of the round-trip delay time or the one-way delay time by using at least the reception bandwidth, and a transmission bandwidth determining unit which determines a transmission bandwidth on the basis of the value of the corrected round-trip delay time or the corrected one-way delay time.

An architecture for measurement of per-hop, one-way delay includes a input observation circuit (24) at the input interface of a node (12) and a output observation circuit (26) at the output interface (16) of a node (12). The input observation circuit (24) copies and time stamps the headers of incoming packets, and filters packets according to an aggregate definition. Similarly, the output observation circuit (26) copies and time stamps the headers of outgoing packets, and filters packets according to the aggregate definition. The incoming and outgoing traces are correlated to calculate a delay measurement. A packet loss measurement uses input observation circuits (72a and 72b) at the input interfaces (14) of upstream and downstream nodes (20 and 22) and an output observation circuit 74 at the output interface (16) of the upstream node. The observation circuits (72a, 72b and 74) determine the number of lost packets across a node and between nodes, according to an aggregate definition.

A computerized method of optimizing audio quality in a voice stream between a sender and a receiver VoIP applications, comprising: defining by the receiver time intervals; determining by the receiver at the end of each time interval whether congestion exists, by calculating (i) one-way-delay and (ii) trend, using double-exponential smoothing; estimating by the receiver a bandwidth available to the sender based on said calculation; sending said estimated bandwidth by the receiver to the sender; and using by the sender said bandwidth estimate as maximum allowed send rate.

This invention provides a kind of measuring method for unidirectional delay, which is message transmission delay from transmitting part to receiving part. It concludes: A) transmitting part keeps the delay to the neighboring next node in the current message and transmits it to the neighboring next node; B) the node, which receives the said message, is used as current transmitting part. Step A is repeated until current node is receiving part; C) receiving part abstracts each delay kept in the message and calculates total delay. Or when transmitting message to next node every time, the kept delays are accumulated. This invention does not need time synchronism between network node facilities to achieve precise unidirectional delay measuring.

A jitter buffering system and a method of jitter buffering. The jitter buffering system may be embodied in a quality of service (QoS) management server, including: (1) a network interface controller (NIC) configured to receive one-way-delay statistics regarding a video stream transmitted to a client, and (2) a processer configured to employ the one-way-delay statistics to calculate and recognize jitter and subsequently generate a command for the client to enable jitter buffering.

A streaming communication device which accurately estimates a packet which will be lost in the future. A streaming communication device which transmits or receives a stream via a router over a packet-switched network, the streaming communication device including: an accumulating unit (204) configured to accumulate a one-way delay that is a time period between transmission and reception of a packet which includes a small segment of the stream; a detecting unit (202) configured to detect a sign of a packet loss by identifying a tendency toward an increase in the one-way delay accumulated in the accumulating unit (204); and an estimating unit (203) configured to estimate, when the sign is detected, a loss packet from a degree of the increase in the one-way delay accumulated in the accumulating unit (204), the loss packet being a packet which will be lost.

An apparatus for and method of estimating a one-way delay time between two hosts and an apparatus and method of clock synchronization using the same. The two hosts are connected to a network and communicate a predetermined packet; k-th, (k+1)-th, and (k+2)-th transmission times are measured at the first host, and k-th, and (k+1)-th transmission times are measured at the second host; a time difference of the m-th transmission time is measured at the first and second host, where m is k or k+1, and by using the measured transmission times, an m-th one-way delay time is calculated. If the time difference is identical to the calculated one-way delay time, a value equal to or less than the calculated one-way delay time is determined as the estimated one-way delay time. Accordingly, the estimation error of a one-way delay time is reduced for both symmetrically and asymmetrically connected hosts.

The invention relates to a mixed type one-way delay estimation method, which is suitable for a network control system (NCS). The method comprises the following steps: (1) estimating the one-way delay of a start control initial frame sent from an actuator in the NCS by adopting an online measuring method which is based on router delay compositional analysis, so as to obtain a relatively precise estimated value; and (2) respectively estimating through a series of calculations which are based on rebound trip time (RTT) values recorded by local clocks at both ends of the system and use the obtained start control initial frame estimated value as a reference scalar to obtain the one-way delay values in the forward channel and the backward channel of the NCS. The method not only effectively overcomes the oversized system overhead defect of the online estimation method, but also has remarkably improved precision of the estimated value compared with the prior end-to-end one-way delay estimation method, so as to achieve the purpose of effectively and accurately estimating the one-way delay of the NCS.

The invention relates to a message transmission method and a hybrid access gateway. The method comprises the following steps: receiving a message of which the destination is a home gateway sent by network side equipment through the hybrid access gateway; and when that a first transmission link is congested and a second transmission link is not congested is detected, acquiring a first CIR (Committed Information Rate) of the first transmission link and a second CIR of the second transmission link, classifying the message into a first class message and a second class message, transmitting the first class message through the first transmission link, and transmitting the second class message through the second transmission link. Thus, the first transmission link and the second transmission linkcan be accessed into the hybrid access gateway when the first transmission link is congested and the second transmission link is not congested, and the hybrid access gateway can control the one-way delay of the first transmission link and the second transmission link by reasonably allocating messages transmitted by the second transmission link, so that the problem of packet loss caused by sortingbuffer overflow is avoided, and the transmission efficiency of link transmission is greatly improved.

The invention provides a method for actively measuring an end-to-end path performance of an OpenFlow network and a system adopted by the same. Aiming at the problem that the end-to-end path performance of the OpenFlow network is currently unable to be measured, the efficient measuring method and the system which use an OpenFlow active measurement protocol OFMP and regard a controller as a center are provided. The measuring method and the system can provide technological means and practical tools for debugging of an SDN control program, quantitative analyzing of an SDN architecture and a mechanism and assessing of network behaviors. Under the condition of clock synchronization of equipment, the system sends one packet so that the end-to-end performance parameters such as routing, a one-way delay, a round trip delay, a piecewise one-way delay, and a delay and a packet loss probability between a control plane and a data plane can be efficiently measured. In addition, under the condition that the clock is desynchronized or not-OFMP enabled equipment is provided, the measuring system can still measure part of major performance indexes, and the advantage that the spending for a processing OFMP is little is provided.

The invention discloses a method and device for testing Ethernet real-time service quality on the basis of point-and-point testing, and belongs to the field of Ethernet performance testing. According to the method, testing data packets with timestamp values are sent back and forth between a master device and a slave device, so that measurement of a one-way delay value and one-way delay jitter is achieved, and synchronous operation is accomplished; according to the device, the master device and the slave device are connected through an intermediate network, the master device is used for generating the testing data packets and leading the testing process, the salve device is used for receiving the data packets, and the testing process of the slave device is controlled by the master device. According to the method and device, due to the fact that delay measurement of the master device and delay measurement of the slave device are carried out according to relative clock adjustment of the master device and relative clock adjustment of the slave device respectively, the synchronizing process of the testing time can be accomplished in two steps, a whole network synchronous clock is not needed, special processing of a middle node device is not needed, the testing environment is simplified, precision, achieved by hardware, of a local timer can be at the microsecond level, and the testing process does not have any influence on the normal service.

A method for performing congestion control in a communication system. The method includes transmitting a request message to a node using a first packet with a highest priority and receiving a response message corresponding to the request message using the first packet and at least one of a plurality of second packets, estimating a one-way delay of the first packet according to a round trip time for the first packet, converting one of the one-way delay of the first packet and the one-way delay of at least one of the plurality of second packets into a quality of service (QoS) level using a predetermined upper delay bound for a corresponding packet, and converting the converted QoS level into an effective congestion level representing a congestion degree in a network and performing congestion control using the effective congestion level.

The invention relates to an FFT accelerator with a high throughput rate. The FFT accelerator with the high throughput rate is characterized by comprising a data storage module, an address generation module and an FFT acceleration module, wherein the data storage module is used for reading, writing and transmission of data, the address generation module provides a target address of data transmission for the data storage module, and the FFT acceleration module carries out FFT on the data output by the data storage module. The FFT accelerator with the high throughput rate has the advantages that a one-way delayed feedback structure is adopted, the throughput rate is high, and the storage resources in a chip are effectively saved. The FFT accelerator supports expansion interface input on one hand, and supports ping-pong output on the other and. In the data input process, cache space is not needed, the data are fed into an FFT calculation component directly, and FFT calculation is carried out. In the data output process, inverted-order output is carried out through the cache.