A Novel Algorithm for Establishing a Balanced Synchronization Hierarchy with Spare Masters (BSHSM) for the IEEE 1588 Precision Time Protocol

• Published in: Energies (Basel) Vol. 10; no. 10; p. 1469
• Main Authors: Tien, Nguyen, Rhee, Jong
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.10.2017
• Subjects: Algorithms; Automation; balanced synchronization hierarchy with spare masters (BSHSM) algorithm; best master clock (BMC) algorithm; Clocks; Clocks & watches; Communication; Conflicts of interest; Failure; fast recovery mechanism; Fault tolerance; precision time protocol (PTP); Primaries & caucuses; Protocol; Random numbers; Synchronism; Synchronization; Time synchronization; Wide area networks; United States > US
• ISSN: 1996-1073; 1996-1073
• DOI: 10.3390/en10101469

OCs are slave clocks that synchronize time to their masters that are the BCs to which the OCs are connecting. For the sample network, BCs 3, 8, 11, 12, and 13 have the same stepsRemoved value; and BC 13 has the lowest clockIdentity value, whereas BC 3 and BC 11 have the highest clockIdentity value. Since the sample network has one GM, the BMC algorithm compares the clocks based on the stepsRemoved and clockIdentity values. [...]of this unbalanced hierarchy, BC 13 has to exchange too many messages with its slaves, resulting in the high consumption of processing and network bandwidth. The ANNOUNCE_RECEIPT_TIMEOUT_EXPIRES event then occurs at the expiration of this timeout, plus a random number of announceIntervals is uniformly distributed in the range (0, 1). Since the BC has no other port in the slave state, the BMC algorithm updates the port’s datasets to the master state configuration and the BC changes to the free-running mode.