— In this paper we perform a detailed analysis of point-to-point packet delay in an operational tier-1 network. The point-to-point delay is the time between a packet entering a router in one PoP (an ingress point) and its leaving a router in another PoP (an egress point). It measures the one-way delay experienced by packets from an ingress point to an egress point across an ISP’s network and provides the most basic information regarding the delay performance of the ISP’s network. Using packet traces captured in the operational network, we obtain precise point-to-point packet delay measurements and analyze the various factors affecting them. Through a simple, stepby-step, systematic methodology and careful data analysis, we identify the major network factors that contribute to point-topoint packet delay and characterize their effect on the network delay performance. Our findings are: 1) delay distributions vary greatly in shape, depending on the path and link utilization; 2) afte...
Baek-Young Choi, Sue B. Moon, Zhi-Li Zhang, Konsta