  To properly validate wireless networking solutions we depend on
experimentation. Simulation very often produces less accurate results due to
the use of models that are simplifications of the real phenomena they try to
model. Networking experimentation may offer limited repeatability and
reproducibility. Being influenced by external random phenomena such as noise,
interference, and multipath, real experiments are hardly repeatable. In
addition, they are difficult to reproduce due to testbed operational
constraints and availability. Without repeatability and reproducibility, the
validation of the networking solution under evaluation is questionable. In this
paper, we show how the Trace-based Simulation (TS) approach can be used to
accurately repeat and reproduce real experiments and, consequently, introduce a
paradigm shift when it comes to the evaluation of wireless networking
solutions. We present an extensive evaluation of the TS approach using the
Fed4FIRE+ w-iLab.2 testbed. The results show that it is possible to repeat and
reproduce real experiments using ns-3 trace-based simulations with more
accuracy than in pure simulation, with average accuracy gains above 50%.
