Patent ID: 9565119
Date: 2017-02-07
CPC Classifications: H04L

Claim:
1. A packet analysis method executed by a packet analysis device that analyzes a packet communicated between a first device and a second device on a network, the packet analysis method comprising: receiving, by a communication interface device included in the packet analysis device and coupled to the network, a first acknowledge packet transmitted from the first device and a second acknowledge packet transmitted from the first device after the first acknowledge packet: receiving, by the communication interface device, a plurality of packets transmitted from the second device during a period from reception of the first acknowledge packet by the communication interface device to reception of the second acknowledge packet by the communication interface device, the plurality of packets being respectively different from an acknowledge packet; identifying, by at least one processor included in the packet analysis device, a number of packets corresponding to data transmitted from the second device to the first device among the plurality of packets, by calculating a difference between a first identification number corresponding to the first acknowledge packet and a second identification number corresponding to the second acknowledge packet; storing information on acquisition timings that indicate timings at which the plurality of packets are respectively acquired, the acquisition timings being acquired by the packet analysis device, and information on an interval between the acquisition timings of two adjacent packets from among the plurality of packets in a memory; calculating a ratio of a number of the data packets to the acknowledge packet for each certain timing; deleting the information on the acquisition timings and the information on the interval that are stored in the memory when the ratio is changed; calculating, by the at least one processor a plurality of bandwidth values, a number of the plurality of bandwidth values being identical to the number of packets corresponding to the data, based on the acquisition timings and the interval between the acquisition timings of two adjacent packets from among the plurality of packets; specifying, by the at least one processor, a bandwidth value that is to be removed from the plurality of bandwidth values by comparing the plurality of bandwidth values with each other, and diagnosing, by the at least one processor, analysis data generated by removing the specified bandwidth value from the plurality of bandwidth values.