W-TSN | openwifi TSN

'25 Rel. 1 + AGPLv3

Time slicing based on MAC address

Reserve some queues to send traffic to certain MAC addresses, and control the time share of those queues to perform custom network slicing.

'25 Rel. 1

Hardware timestamping

Hardware timestamping at Tx and Rx side with microsecond accuracy

'25 Rel. 1

Precision Time Protocol

Support for PTP at layer 3 and using boundary clock

'25 Rel. 1

IEEE 802.1Qbv time-aware shaper

A gated mechanism (time slot and cycle for EDCA queues), (dynamic) mapping of packets (DSCP values) to HW queues, set/get schedule and over-the-air schedule distribution

'25 Rel. 1

User-level in-band telemetry (INT)

Per-hop and end-to-end monitoring of (wireless) KPIs, application requirement sharing, feedback, INT mode selection (freq., probability, count), API for controlling INT

'25 Rel. 1

Time-triggered control over Wi-Fi features

Time-triggered configuration of following parameters: CSMA/CA, LBT threshold, NAV, DIFS/EIFS, CW, # ReTx, Tx digital attenuation, Tx/Rx freq. channel, Rx sensitivity

'25 Rel. 1

IEEE 802.11ah encapsulation

Encapsulation in user level to support connecting COTS devices to Wi-Fi STAs

'25 Rel. 2 / '26 Rel. 1

Hardware timestamping+

Hardware timestamping at Tx and Rx side with sub-microsecond accuracy

'25 Rel. 2 / '26 Rel. 1

Bootstrapping

Allow the association of new stations without impacting ongoing W-TSN traffic

'25 Rel. 2 / '26 Rel. 1

Reliability & scheduling

Novel features in support of reliability and scheduling such as fast ReTx, flexible TxOP, DL C-SR, etc.

'26 Rel. 2+

Precision Time Protocol++

Extended PTP capabilities including layer 2 and resilience against wireless channel errors

'26 Rel. 2+

Coordinated beaconing/scanning & probing

Enable beaconing, scanning and probing without impacting W-TSN traffic, in order to support mobility

'26 Rel. 2+

Scheduling

SW-based credit-based shaper, full OFDMA combined with TSN, μslots, slot-crossing protection, dynamic queuing, preemption techniques

'26 Rel. 2+

Reliability

basic MLO (2 APs – 2 STAs), UL MLO FRER, full-duplex MLO, c-OFDMA

'25 Rel. 1

Available with the first release in 2025

'25 Rel. 2 / '26 Rel. 1

Available with the second release in 2025 or first release in 2026

'26 Rel. 2+

Available with the second release in 2026 or later

+ AGPLV3

Also available under free AGPLv3

Research possibilities with W-TSN

Bootstrapping new nodes

Bootstrapping refers to the process of establishing initial network connectivity, including association and configuration on a wireless device. This process becomes particularly critical in a TSN environment, as it may not interrupt any of the time-critical traffic flows. Hence, an efficient association procedure has been designed that is both Wi-Fi and TSN compatible.

Deterministic handovers

Mobility remains a fundamental asset in wireless communications, whereas time-sensitive networking (TSN) is vital to guarantee determinism and low latency. We marry these two concepts by introducing a procedure that enables seamless roaming within a Wi-Fi-based TSN with delays as low as 20ms.

ML-assisted handovers in W-TSN

Through real-world development and testing, we present an optimized approach for minimizing handover delay and leveraging machine learning to select the optimal handover time and space moment in a two-dimensional environment, with low effect on time-sensitive traffic. Our findings demonstrate that our mechanism reduces handover delay below 10 milliseconds and optimizes the handover moment selection, leading to improvements in critical network parameters such as bandwidth and jitter.

/Coordinated%20SR%20and%20Restricted%20TWT%20in%20Wi-Fi%207

Coordinated SR and Restricted TWT in Wi-Fi 7

With the advent of WiFi 7, also known as IEEE 802.11be, more coordination is foreseen between different access points (APs), bringing the possibility to support time-critical traffic in wireless networks as well. Boosted coordination between APs improves the throughput under dense deployed Wi-Fi networks, as well as giving support for prioritized channel access for certain devices and traffic flows. We showcase and assess a real implementation of both features (C-SR and R-TWT) on top of the openwifi TSN platform.

/A%20centralized%20approach%20for%20C-SR

A centralized approach for C-SR

With dense network deployments, interference between overlapping basic service set (OBSS) becomes the main source of system throughput drop and packet delays. With coordinated spatial reuse (C-SR), APs operating on the same channel accurately determine the levels of interference and modulation and coding scheme (MCS) index to be used for concurrent transmissions. Using our W-TSN design, we designed a centralized algorithm that orchestrates such concurrent transmissions in time, resulting in increased goodputs.

Dynamic traffic classification

With dynamic traffic classification, we are able to give faster dedicated access to the wireless medium for packets of highly-time-sensitive flows, that can be generated randomly. Dynamic traffic classification utilizes so-called shadow queues implemented at the FPGA-level of openwifi to prioritize channel access of certain packets over others. This way, we achieve to decrease the end-to-end latency by 75% in case of longer communication cycles with wider space between communication time slots.

PROFINET over W-TSN

In the wireless domain, scheduling becomes more challenging than in wired TSNs due to the shared medium, lower reliability, and slower transmission rates compared to wired systems, reducing the available time resources. We studied genetic algorithms to support scheduling of traffic flows from different wireless end devices in a shared schedule.

More to come

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