  With the ratification of the IEEE 802.15.3d amendment to the 802.15.3, a
first step has been made to standardize consumer wireless communications in the
sub-THz frequency band. The IEEE 802.15.3d offers switched point-to-point
connectivity with the data rates of 100\,Gbit/s and higher at distances ranging
from tens of centimeters up to a few hundred meters. In this article, we
provide a detailed introduction to the IEEE 802.15.3d and the key design
principles beyond the developed standard. We particularly describe the target
applications and usage scenarios, as well as the specifics of the IEEE
802.15.3d physical and medium access layers. Later, we present the results of
the initial performance evaluation of IEEE 802.15.3d wireless communications.
The obtained first-order performance predictions show non-incremental benefits
compared to the characteristics of the fifth-generation wireless systems, thus
paving the way towards the six-generation (6G) THz networks. We conclude the
article by outlining the further standardization and regulatory activities on
wireless networking in the THz frequency band.
