Abstract
Functional safety has become a crucial part of industrial automation. With industry environments being connected
more than ever, achieving required functional safety depends on
establishing safety-critical communication. Numerous application
layer safety protocols have been developed to ensure compliance
with functional safety standards for wired communications.
However, with all the benefits wireless communications entails,
wireless communication is pushing for an important place in
the future of industrial automation. It is important that safety
protocols also follow this transition and are able to operate as intended using a wireless channel. By default, openSAFETY frames
are exchanged using UDP broadcast, whereas TCP provides
additional reliability features. Thus, the aim of this paper is to
analyze if safety-critical communication using a wireless channel
can benefit from the additional reliability features provided by
TCP. To answer this, we experimentally analyze the performance
of openSAFETY protocol providing functional safety over the
IEEE 802.11 standard for three different test cases. We analyze
the performance in terms of median end-to-end delay and time
spent by a safety node in a safe state for both protocol stacks.
Results show that UDP provides lower median end-to-end delay,
whereas TCP is able to achieve less time spent in a safe state
under bounded delay constraint.
more than ever, achieving required functional safety depends on
establishing safety-critical communication. Numerous application
layer safety protocols have been developed to ensure compliance
with functional safety standards for wired communications.
However, with all the benefits wireless communications entails,
wireless communication is pushing for an important place in
the future of industrial automation. It is important that safety
protocols also follow this transition and are able to operate as intended using a wireless channel. By default, openSAFETY frames
are exchanged using UDP broadcast, whereas TCP provides
additional reliability features. Thus, the aim of this paper is to
analyze if safety-critical communication using a wireless channel
can benefit from the additional reliability features provided by
TCP. To answer this, we experimentally analyze the performance
of openSAFETY protocol providing functional safety over the
IEEE 802.11 standard for three different test cases. We analyze
the performance in terms of median end-to-end delay and time
spent by a safety node in a safe state for both protocol stacks.
Results show that UDP provides lower median end-to-end delay,
whereas TCP is able to achieve less time spent in a safe state
under bounded delay constraint.
| Original language | English |
|---|---|
| Title of host publication | 2021 IEEE 26th Conference on Emerging Technologies & Factory Automation (ETFA) |
| Chapter | 5 |
| Number of pages | 8 |
| ISBN (Electronic) | 978-1-7281-2989-1 |
| DOIs | |
| Publication status | Published - 9 Sept 2021 |