Patent ID: 9288002
Filing Date: 2016-03-15
CPC Classification: H04J

Claim Text:
1. A method for forwarding a timing related alarm in a packet-switched network that includes a master node and a slave node operative to exchange Precision Time Protocol (PTP)-type messages to enable the slave node to obtain timing of the master node, wherein said method comprising: selecting an intermediate network node located at a path extending between the master and slave nodes to serve as a quasi-slave node; ensuring that the intermediate network node is configured to passively process the PTP-type messages, wherein passively processing the PTP-type messages includes generating a plurality of local timestamps that includes at least a first timestamp of a first PTP-type message received from the master node and at least a second timestamp of a second PTP-type message received from the slave node, the plurality of local timestamps are used for internal processing at the intermediate network node; at the intermediate network node, passively processing a plurality of PTP-type message exchanged between the master node and a slave node; at the intermediate network node, calculating a value derived from at least the first timestamp and the second timestamp; at the intermediate network node, determining that the value does not meet at least one predetermined criterion; and when said value does not meet the at least one predetermined criterion, forwarding a timing related alarm to a network managing entity.