Presently, most of the network measurement tools are active. But they bring heavy overhead and impact the measurement accuracy. We concern how to ensure measurement accuracy with reducing the overhead. In this work, a new measurement scheme iPathneck based on Pathneck is proposed to perform better than Pathneck on measuring ABW by using probe rate model. iPathneck combines tasks to measure ABW and to locate Internet bottleneck. Experiment will show that iPathneck achieve shorter convergence time, lighter measurement overhead and higher accuracy.