Reaching self-stabilising distributed synchronisation with COTS Ethernet components: the WALDEN approach

For reaching deterministic self-stabilising distributed synchronisation with commercial-off-the-shelf (COTS) Ethernet, this paper explores the Wire-Adapted Linker-Decoupled EtherNet (WALDEN) architecture with the integration of several mass-produced COTS products. Upon this architecture, basic strategies of distributed synchronisation are discussed. Self-stabilising algorithms are presented and formally analysed. Besides, a prototype system is realised with COTS switches, PHY chips, and low-end ARM series under the WALDEN architecture with a minimum hardware modification. The experimental result shows that a sub-microsecond synchronisation precision can be achieved with this prototype implementation even in the presence of low-quality switch with non-queuing delay-jitters of several microseconds. Among existing solutions, this work features in considering the distributed synchronisation, backward-compatibility, and self-stabilisation problems as a whole.