31 results about "Packet scheduling algorithm" patented technology

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. In a packet schedule weighting equation, a value of exponent may be varied from negative to positive to give good (or bad) users better service. However, performance of users with bad channel qualities degrades the performance of good channel users in a disproportionate manner. It is shown that it is frequently preferable to favor users with good channel qualities.

A system comprises a base station, a plurality of mobile stations, and a packet scheduling algorithm that operates on the base station. The packet scheduling algorithm groups the plurality of mobile stations into a plurality of groups based on average throughput with the base station. The packet scheduling algorithm selects one of the plurality of groups for applying a scheduling metric.

The invention discloses a CICQ structure switch packet scheduling algorithm based on virtual queue length coordination single multicast competition. The algorithm provided by the invention includes two parts: input scheduling and output scheduling. In the input scheduling, first find out the output port with the minimum sum of columns and cross-node buffer groups, and then select the destination port of the unicast header cell and the multicast header cell among the input ports that have cells going to the output port, and Set the input port with the fewest elements, calculate the weight of the unicast header cell and the multicast header cell, select the header cell with the largest weight, and transmit it to the corresponding cross-node buffer. In the output scheduling, the weight of the cross-node cache is equal to the sum of the corresponding unicast queue captain and the virtual captains of all the multicast queues whose header cells go to its corresponding output port, and the packet in the cross-node cache with the largest weight leaves the output port. Compared with the typical method, the algorithm provided by the invention has better throughput rate and packet average delay performance.

The invention discloses a CICQ structure crossbuffer queue balance packet scheduling algorithm. According to the CICQ structure crossbuffer queue balance packet scheduling algorithm, making a switch work in a work-conserving state as a core is realized or is approached to a maximum degree, output ports are taken as matching reference, output ports having smallest crossbuffer queue length are selected for priority matching, crossbuffer packet occupation of all output ports is balanced, so working in the work-conserving state is made to realize or approach to a maximum degree, the passing percentage is improved, and average packet time delay is further reduced. As is shown in simulation result comparison, for the CICQ switch with crossbuffer as one packet, the algorithm is better than known mainstream algorithms in the average packet time delay, and excellent practical values in large-scale high performance CICQ switches are realized.

The invention discloses a GEO satellite-borne CICQ structure switch single-multicast mixed service packet scheduling algorithm, which belongs to the technical field of satellite network and high-performance packet switching. The purpose of the present invention is to alleviate the problem of multicast HOL Blocking in the grouping scheduling of CICQ switch in the input-output scheduling algorithm, and at the same time compensate the grouping that needs to be retransmitted due to the transmission failure caused by the GEO channel problem. In the input scheduling, on the premise of making the CICQ switch work as work-conserving as possible, the goal is to alleviate the blocking of the multicast queue head group to the secondary group. In single-multicast packet arbitration, the number of times the packet is retransmitted in the channel is considered as the primary factor. In the output scheduling, the goal is to alleviate the blockage of the sub-packet by the cross-buffer corresponding to the head of the multicast queue. The invention fully considers the characteristics and requirements of the GEO satellite network, and has good practical application value.

The invention provides the technical scheme of an on-line certificate state query method for a dynamic packet scheduling algorithm on the basis of a limited priority level. The scheme is based on the limited priority level dynamic packet scheduling algorithm; when a CA (certificate authority) center issues an updated-state digital certificate, the algorithm is utilized to dynamically group and store the updated digital certificate into a CA database, and a characteristic identifier is correspondingly added; and when the digital certificate state is queried, the characteristic identifier is matched to look up the priority level group corresponding to the digital certificate to obtain the real-time state of the digital certificate. According to the method, the query time of the data base is reduced, the query time is shortened, the query efficiency is improved, and the on-line certificate state query method has a good applicability for the financial stock exchange and the bank in which the effectiveness of the digital certificate is frequently verified and the state of the digital certificate changes frequently.