1088results about How to "Reduce the probability of packet loss" patented technology

Via real time online bandwidth measurement, this method confirms the threshold value ssthresh. When the congestion window (CW) is less than a half of the threshold, the rule of exponent gain is followed. Otherwise CW gains each time a value of a half of difference of the threshold and CW (ssthresh-cwnd) to approach gradually the threshold. Until the difference is less than the regulation factor phi (ssthresh/2>= phi >=2). Then CW is set as the threshold value to enter the stage of avoiding congestion. This invention can reduce the happening of loss of several texts in a window at the slowly start stage, reduce the package loss rate and raise the net transferring ability.

The invention relates to a multi-path transmission control terminal and a method for supporting multi-service data transmission, and belongs to the technical field of network communication. The terminal is arranged on an end point of data transmission and comprises a multi-path session management module, a path management module, a flow division module, a path selection module, a substream sending control module, a substream receiving control module, a rectification recombination module, a path transmission quality report module and a path evaluation module. When data stream of an upper application is received, the data stream is divided into stream blocks, a path is selected for each stream block, stream blocks dispatched to the same path form a substream, the stream blocks are further divided into transmission units and are packaged into multi-path transmission packages and are transmitted to an opposite terminal, according to the path transmission quality fed by the opposite terminal, a path selection strategy is dynamically adjusted; when the multi-path transmission data packages are received, substream data is recombined and is further recombined into data streams and the data streams are transmitted to the upper application. The terminal and method can meet different transmission requests of various business types, and the multi-path transmission efficiency is improved.

Under condition of not increasing network load, using accurate effective feedback information provided by client end, the method analyzes and judges state of current network. Based on the analyzed result, the method adjusts size of RTP packet, and sending speed of video basic stream so as to realize dispatch control by server end. The method reduces time delay from server end to client end and rate of packet loss without increasing network burden. Transferred video provides good subjective effect.

The invention discloses a data center network routing method based on a Fat-Tree structure, and belongs to the technical field of data center networks. The SDN technology is used by the method, the data stream size and the link transmission condition are comprehensively considered in a data center network of a Fat-Tree structure and having multipath transmission ability, and new streams entering the network are routed by using a dynamic load balancing (DLB) algorithm based on residual link bandwidth and the number of large streams; and after link congestion is detected, the large streams on the congested link are re-scheduled by using a dynamic re-routing (DR) algorithm based on deadline and switch queue length from large to small, until the link is not congested. By adoption of the data center network routing method disclosed by the invention, the load balance of data streams in the data center network can be realized, the routing strategy can be dynamically adjusted according to the network state, the utilization rate and the throughput of the link are improved, and the forwarding delay and the packet loss rate of the data streams are reduced.

Computer-implemented methods and computer systems for identifying whether there exists building permit information associated with a structure, or for estimating underinsurance of condition of a structure are provided. The computer implemented methods include acquiring construction information on a plurality of structures in computer-readable form and converting the construction information into a standardized database. The construction information may include building permit data including one or more of the number of building permits within a particular time frame, building permit age, building permit category, and job cost. Further, the computer implemented methods may include estimating underinsurance or condition of a target structure based on the construction information.

An embodiment of the invention provides a method, a device and a system for network package processing, response time of the system can be reduced, system resources are saved, and the efficiency of the network package processing is improved. The method includes the steps that a network package is received and is cached into a first address of an internal memory buffer area; according to the address mapping relation among the first address of the internal memory buffer area, an address of a prestored internal memory buffer area and a physical address of a video memory of a graphics processor (GPU), the physical address of the network package in the video memory of the GPU is determined; a direct memory access (DMA) controller is controlled to write the network package into the determined physical address of the video memory of the GPU where the network package is in; and first indication information is sent to enable a communication opposite end to process the network package according to the first indication information, wherein the first indication information carries the determined physical address of the network package in the video memory of the GPU. The method, the device and the system are applied to the field of computers.

The invention discloses a Hadoop-based distributed intrusion detection system which comprises a data acquisition module, a data storage module, a control center and a data analysis module, wherein the control center comprises a system management module, a system monitor module, a task scheduling module and an alarm response module. By utilizing a Hadoop-based distributed computation framework, the system is allowed to have good interoperability, and the system reliability is improved; the system carries out data parallel acquisition through a distributed mode, thereby improving data acquisition capability and reducing packet loss probability; in an algorithm adopted in the system, data is allocated according to capacity and load of nodes, and adjustment is carried out by utilizing a dynamic load balancing strategy, so that data processing capacity of the nodes is given effective play to, and load balancing of the system is maintained; and through the algorithm, the case of distributing the data comprising the same attack to two or more detection nodes for processing separately, which damages integrity of the data, is prevented, and detection efficiency is improved effectively.

The invention discloses a method for multiuser collaborated transmission for data based on service features, characterized in that short distance connection is established between voice user and data user, voice user can serve as collaborated user, employs voice channel for accomplishing uplink and downlink transmission during idle period of voice. The invention effectively promotes voice channel utilization efficiency without influencing voice service quality, can improves data service quality when telephone traffic is busy.

The invention relates to a method for achieving a real-time video monitoring system based on an internet protocol television top-set box, which is a method for achieving the function of real-time video monitoring on the internet protocol television (IPTV) top-set box. Based on an added-value extended function provided by an IPTV peer-to-peer computing top-set box developed on a dual-core development platform TMS320DM6446 (Vinci digital platform), the invention provides the method for achieving the real-time video monitoring system based on the internet protocol television top-set box for achieving a household real-time video monitoring system on the IPTV top-set box developed on the basis of the DM6446 platform so as to solve the problems of the read-write operations driven by a video capture device, the call of a DSP MPEG-4 coding interface, the transmission and the control of a RTP (Real-time Transport Protocol) data pack, the achievement of MPEG-4 decoding, and the multimedia interface display based on SDL. The proposal has the advantages of novelty, flexibility, easy expansibility, easy operability, low cost and the like.

An embodiment of the invention discloses a determination method of a downlink process number and a device thereof. Through applying a technical scheme of the embodiment, starting from a downlink SPS (semi-persistent scheduling) activation subframe, a base station and a terminal device respectively determine downlink process numbers corresponding to each pre-configured downlink SPS resource in order, thus reasonable distribution of the process numbers are ensured, a data packet loss ratio is reduced, a situation that a downlink HARQ (hybrid automatic repeat request) process number which is calculated and obtained is inconsistent with an expected used process number caused by SFN (system frame number) overturn is avoided, and a packet loss situation caused by that a data packet can not be retransmitted also is solved.

The invention discloses a routing method for a heterogeneous network based on cognition, mainly solving the problem that the existing method considers only part of environment factors of the network, and neglects the dynamic complexity of a heterogeneous network environment so as not to cognize and predict the environment. The method comprises the following steps: firstly, judging the types of the existing available networks, perceiving a network environment state, evaluating the network environment state by using a Q-learning method and calculating end-to-end time delay and the estimated values thereof; secondly, using a utility function based on multiple parameters to obtain the utility values of various networks according to the perceived network environment state; then selecting the network with the biggest utility value by a probability of P=0.9, and selecting other available networks as target networks by the probability of 1-P; and finally continuously transmitting businesses, implementing network switch and updating the network environment state by the target networks. The routing method improves the utilization ratio of network resources, achieves load balance of the network and can be used in the heterogeneous network environment.

The invention discloses a method for optimizing the video quality of service (QoS) of a video wireless transmission monitoring system. In the wireless communication process of a video signal acquisition processing transmission terminal and a video signal receiving play server, the video signal receiving play server counts video stream data packets sent by the video signal acquisition processing transmission terminal in real time, analyzes and judges the data packets, and sends feedback information to the video signal acquisition processing transmission terminal when a video parameter is needed to be adjusted, and the video signal acquisition processing transmission terminal receives the feedback information and adjusts the video parameter. By the method, video resolution and code stream are dynamically adjusted, and the transmission characteristic is controlled in real time, so that the packet loss rate is reduced, the definition of a transmitted frame is increased, the utilization rate of a wireless network is improved, and video transmission quality and stability are greatly improved; therefore, the video wireless transmission monitoring system can adjust video transmission code rate and resolution at different times according to the real-time condition of the network.

The invention provides a channel selection method and a channel selection system based on a WLAN wireless channel grading mechanism. The channel selection method comprises the following steps: step 1, scanning a current wireless channel, and making statistics about a wireless signal intensity indication values of each wireless router to a newly accessing wireless router on each wireless channel; step 2, working out the wireless channel with the lowest disturbance according to the wireless signal intensity indication values; and step 3, connecting to the wireless channel with the lowest disturbance. The channel selection method and the channel selection system are applicable to situations with complicated wireless environment and data disturbance among the wireless channels; when the router accesses the wireless network, the wireless router can automatically select an optimal wireless channel, so that the wireless data transmission efficiency is improved, the disturbance among the wireless channels is effectively reduced, the packet loss probability is reduced, and the quality of service of the wireless network is improved.

The invention discloses a self-adaptation vertical handover method based on an RSS (Really Simple Syndication) variation trend, belonging to the technical field of wireless networks. The self-adaptation vertical handover method comprises the following steps: setting a handover execution threshold value for each candidate network by setting a handover trigger threshold value for a current service network; then measuring the strength value of received signals of the current service network and all the candidate networks and a round-trip time delay value of the current service network, and generating a signal strength sequence and a time delay sequence through normalization processing; and then, respectively averaging the signal strength sequence and the time delay sequence, then updating network evaluation values of all networks, and optimizing the handover triggering threshold values and the handover execution threshold values to realize the self-adaptation vertical handover. In the method, a linear weighting method is used for evaluating a heterogeneous network, meanwhile, a handover judgment threshold value is regulated in a self-adaptation manner according to the variation trendof the strength of the received signals, and thus, rapid and accurate vertical handover is realized.

The invention relates to an industrial wireless sensor network communication method based on relay nodes, belonging to the field of sensor network communication. A network management center distributes a preferred communication path resource according to the request of a source node and current network state information, selects a relay node and a relay path according to constraint conditions, and distributes the communication resources of the relay path. In the communication process, when the relay node receives the negative response from the node of the last hop, the probability that the transmission delay exceeds a threshold is reduced, the frequency of retransmission initiated by the source node is reduced, and the energy consumption for retransmitting data is reduced. Meanwhile, the relay node also dynamically changes the priority of data packets, avoids delaying transmission of the data packets again, and ensures that the data packets reach a destination node in delay requirements. By adopting collaboration among the relay node, the destination node and the network management center, the packet loss rate is reduced, the frequency of retransmission initiated by the source node is reduced, and the energy consumption for retransmitting data is reduced.

The invention discloses a vehicle-mounted delay tolerant network routing method based on node forwarding capability estimation. The vehicle-mounted delay tolerant network routing method comprises: a step 1: judging whether a destination node exists within the communication range of a source node, and if so, directly sending information to the destination node; otherwise, executing a step 2; step 2: estimating effective connection times Ta of the source node with all neighbor nodes within the communication range thereof; a step 3: selecting neighbor nodes with Ta values exceeding a threshold as candidate relay nodes; a step 4: creating a candidate relay node throughput function, and calculating average forwarding capability values of the candidate relay nodes; a step 5: using the candidate relay node having the maximum average forwarding capability value as a next hop relay node; a step 6: selecting the relay node through the source node, sending the information to the relay node, and using the relay node as a new source node; and a step 7: circularly executing the step 1 to the step 6 until streaming media information is successfully transmitted to the destination node. The vehicle-mounted delay tolerant network routing method disclosed by the invention is high in data packet delivery ratio, low in transmission delay and low in delay jitter.

The invention relates to a distributed cooperative caching method capable of realizing node and message state combined perception and belongs to the technical field of a distributed cooperative caching technology for opportunistic networks. The method aims to solve the problem of the lower node caching efficiency at present, dissemination states of messages are perceived, weight values of the messages are dynamically estimated, and the encounter probability of nodes and message target nodes is predicted with an encounter probability estimation method; then the messages are cached in a classified manner on the basis of differences between message source nodes, different caching priorities are given, and the messages in node caches are replaced in a cooperative manner with a cooperative partition cache replacement mechanism, so that the caching efficiency of the nodes is improved; finally, in order to solve the problem of decrease of the message delivery rate caused by unchecked deletion of messages in a traditional cache management mechanism, a distributed cooperative cache transfer mechanism is adopted, top-k cooperative node sets of the nodes are dynamically selected in advance, and the messages in the node caches are transferred to cooperative nodes in a communication range when the node caches are full, so that the delivery probability of the messages is increased.

The invention discloses a 3G media stream cross-layer rate control method based on channel measurement. According to the method, wireless channel quality is estimated through ARQ message of an RLC layer for transmission characteristics of a 3G/UMTS air interface so as to distinguish packet loss types, and a server will be used to judge the network congestion situation and adjust the sending rate according to the channel quality which is fed back and the time delay change trend by means of the time delay measurement error brought to the transmission layer caused by the RLC layer eliminating ARQ mechanism, the packet loss rate and the throughput performance have substantial characteristics and significant improvements compared with the prior art, so the method can be used to ensure that end-to-end QoS requirements of media services can be fully satisfied by the rate control.

The invention discloses a method for data transmitting data when a heterogeneity IP network is switched, a heterogeneity IP network system and a core network gateway. The core network gateway is used as different anchor point accessed to the system for the heterogeneity IP network. When the user terminal starts a switching in the heterogeneity IP network, the source network is used for sending a instruction information of retaining business to the core network gateway; the core network gateway carries out a caching to the sent business data of the user terminal according to the instruction information; after the switching is completed, the user terminal sends instruction information of canceling the detainment to the core network gateway through the target network; the core network gateway sends the cached business data to the user terminal according to the instruction information. By adopting the invention, when an activated state user terminal switches between the heterogeneity IP networks, a packet loss rate can be reduced and the switching relay also can be reduced.

The invention discloses an H264-based real-time mobile video service control method, which belongs to the field of real-time streaming media and mobile network transmission. The method includes the following steps: a real-time video is coded according to H264, a low bit rate and low resolution, the coded H264 video data are then packed, the processed video data is transmitted to a mobile terminal according to the real-time stream transmission protocol, a three-phase bit rate control method is adopted, the status of a mobile network channel is detected and fed back by a transmission control mechanism in the process of transmission, and according to feedback information, bit rate control is carried out at the coding end. Finally, the transmitted video data is decoded and displayed by the mobile terminal. The method can effectively guarantee the real-time mobile video service quality in a mobile network environment.