  The IEEE 802.11ad WiFi amendment enables short-range multi-gigabit
communications in the unlicensed 60~GHz spectrum, unlocking new interesting
applications such as wireless Augmented and Virtual Reality. The
characteristics of the mmWave band and directional communications allow
increasing the system throughput by scheduling pairs of nodes with low
cross-interfering channels in the same time-frequency slot. On the other hand,
this requires significantly more signaling overhead. Furthermore, IEEE 802.11ad
introduces a hybrid MAC characterized by two different channel access
mechanisms: contention-based and contention-free access periods. The
coexistence of both access period types and the directionality typical of
mmWave increase the channel access and scheduling complexity in IEEE 802.11ad
compared to previous WiFi versions. Hence, to provide the Quality of Service
(QoS) performance required by demanding applications, a proper resource
scheduling mechanism that takes into account both directional communications
and the newly added features of this WiFi amendment is needed. In this paper,
we present a brief but comprehensive review of the open problems and challenges
associated with channel access in IEEE 802.11ad and propose a workflow to
tackle them via both heuristic and learning-based methods.
