By dealing with the raw giant data samples authorized by CAIDA

we obtain one-way link delay.Together with the ratio of the biggest link delay to the end-to-end delay and the distribution of the Internet hops

the dominant delay is defined.Analysis on the impact of link delay on the end-to-end delay reviews that discrepancy of dominant delay primarily accounts for the multi-modal distribution of end-to-end delay.Besides

dominant delay tends to position more preferentially on the middle part of paths and inside the AS

which indicates that the delay bottleneck was shifted from access part to transmission part.At last

conclusion is draw that propagation delay is the major composition of the dominant delay as the effect of transmission delay declined.