  The increasing demand of data, along with the spectrum scarcity, are
motivating a urgent shift towards exploiting new bands. This is the main reason
behind identifying mmWaves as the key disruptive enabling technology for 5G
cellular networks. Indeed, utilizing new bands means facing new challenges; in
this context, they are mainly related to the radio propagation, which is
shorter in range and more sensitive to obstacles. The resulting key aspects
that need to be taken into account when designing mmWave cellular systems are
directionality and link intermittency. The lack of network level results
motivated this work, which aims at providing the first of a kind open source
mmWave framework, based on the network simulator ns-3. The main focus of this
work is the modeling of customizable channel, physical (PHY) and medium access
control (MAC) layers for mmWave systems. The overall design and architecture of
the model are discussed in details. Finally, the validity of our proposed
framework is corroborated through the simulation of a simple scenario.
