| 摘要 |
<p>A hierarchical synchronization method for a telecommunications system employing message-based synchronization and comprising a plurality of nodes interconnected by transmission lines (A, B). The nodes interchange signals comprising synchronization messages with a synchronization signature indicating the priority of the corresponding signal in the internal synchronization hierarchy of the system and containing information about the distance to the network master clock and about the original synchronization source. The node monitors the distance parameter contained in the synchronization signature of a source on the top of the priority list and describing the distance to the master source of synchronization, and in a change situation, such as a failure situation, changes over from the normal state to a predetermined state in order to prevent the selection of faulty synchronization signatures. In order that an outdated synchronization signature circulating in the network would be detected as simply as possible, the node also monitors the parameter describing the original synchronization source.</p> |
