User-friendly bottleneck detection algorithm

It is very difficult to identify the location of bottlenecks when there is deterioration of Quality of Service (QoS) because current Internet service is the complicate structure which is provided through a number of ISP. This paper proposes bottleneck detection algorithm which can detect the bottleneck point easily and efficiently even though there is no prior knowledge of the network connection status. The execution procedure of the proposed algorithm can be largely divided into two phases. In the first phase, the proposed algorithm finds the choke point which is suspected to be the bottleneck point using Recursive Packet Train (RPT). In second phase, it identifies the bottleneck point by monitoring packet process time of the detected choke point. For this, this paper proposes two methods. The first method monitors packet process time of the choke point utilizing timestamp option. This method has the advantage which can monitor the bottleneck point without increasing network load because it uses passive monitoring approach using the IP header part of the data packet of the actual users. But agent should be run in all of servers and clients. The second method monitors packet process time of the choke point utilizing ICMP packet. This method is possible to detect the bottleneck point by running agent solely in client without running agent of servers because ICMP packet which is sent to the senders to report the problems found while processing IP packet in routers.