You Are a Network Engineer for the P4S Ltd

Multiple Choice

You are a network engineer for the P4S Ltd. You are measuring one-way delay between two campus networks connected through an MPLS network. One campus is in Chicago and the other is in Dallas. The company has one appliance at each campus with which to measure the delay. Which of the following is a must for the two appliances in order for the engineer to measure one-way delay with the best possible accuracy?

A) connections to the CE routers
B) a common TOD reference source
C) a local Stratum 1 clock source
D) the same physical interface to the network