  One of the essential requirements of wireless industrial Internet of Things
(IoT) systems is to have an extremely high packet delivery rate, generally over
99.9% and comply wih realtime deadline constraints. In industrial IoT networks,
packets arriving after the deadline become part of packet loss and lose meaning
when they arrive late. However, currently available industial IoT proposals aim
to minimize End-to-End delay without taking into account simultaneous realtime
and reliability constraints. In this paper, we propose a new mechanism, called
BDPC (Bounded Delay Packet Control) to tackle this challenge. BDPC combines the
knowledge of a node's traffic delay to the destination (root) with the time
budget of a data packet traversing the industrial IoT network, to allocate
network resources to comply the system maximum delay requirements using an
adaptive and distributed algorithm. Unlike the general aim to minimze
end-to-end delay, we propose that data packets must arrive before the deadline,
but not faster. Our results show, for example, that by using BDPC, the number
of packets arriving before the deadline can be improved more than 2.6 times
compared to the case when using the default Minimal Scheduling Function from
the standard. As a further advantage, BDPC involves minor modifications to the
6TiSCH protocol stack, which makes it compatible with current implementations.
