Self-checking pair-based master/follower clock synchronization
First Claim
1. A method for clock synchronization in a braided ring network comprising a plurality of nodes, wherein at least two nodes of the plurality of nodes comprise a self-checking pair of a first node and a second node, the method comprising:
- determining at the first node when a first rendezvous message is received from the second node;
when the first rendezvous message is received from the second node, calculating at the first node a time difference between a send instance of the first rendezvous message and a local time;
when the time difference is not greater than a reference bound, calculating at the first node a common sending point for transmitting a first synchronization message, wherein the common sending point is calculated based on the time difference so that the first synchronization message is transmitted at approximately the same point in time as a second synchronization message transmitted from the second node; and
selectively sending the first synchronization message from the first node to at least one node in the braided ring network other than the second node when the common sending point is reached based on the time difference.
1 Assignment
0 Petitions
Accused Products
Abstract
Systems and methods for network clock synchronization are provided. In one embodiment, a method for clock synchronization in a braided ring network comprises: providing a schedule for a braided ring network comprising a plurality of nodes, wherein at least two nodes comprise a self-checking pair of a first node and a second node, the first node performing a method comprising: determining when a first rendezvous message is received from the second node; when the second rendezvous message is received, calculating a time difference between the send instance of the first rendezvous message and a local time; when the time difference is not greater than a reference bound, calculating a sending point for transmitting a synchronization message, wherein the sending point is calculated based on the time difference; and selectively sending the synchronization message to the braided ring network when the sending point is reached based on the time difference.
-
Citations
13 Claims
-
1. A method for clock synchronization in a braided ring network comprising a plurality of nodes, wherein at least two nodes of the plurality of nodes comprise a self-checking pair of a first node and a second node, the method comprising:
-
determining at the first node when a first rendezvous message is received from the second node; when the first rendezvous message is received from the second node, calculating at the first node a time difference between a send instance of the first rendezvous message and a local time; when the time difference is not greater than a reference bound, calculating at the first node a common sending point for transmitting a first synchronization message, wherein the common sending point is calculated based on the time difference so that the first synchronization message is transmitted at approximately the same point in time as a second synchronization message transmitted from the second node; and selectively sending the first synchronization message from the first node to at least one node in the braided ring network other than the second node when the common sending point is reached based on the time difference. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A synchronizing system for a network, the system comprising:
-
a first node having a first local clock, the first node communicatively coupled to a first channel of the network; a second node having a second local clock, the second node communicatively coupled to a second channel of the network; at least one link communicatively coupling the first node to the second node, wherein the first node and the second node transmit rendezvous messages to each other over the at least one link; wherein the first node determines when a rendezvous message is received from the second node, and determines a first time difference between the first local clock and the second local clock based on a send time instance of the rendezvous message from the second node; wherein the first node calculates a first common sending point for transmitting a first synchronization message to at least one node other than the second node on the first channel based on the first time difference; wherein the second node determines when a rendezvous message is received from the first node, and determines a second time difference between the first local clock and the second local clock based on a send time instance of the rendezvous message from the first node; and wherein the second node calculates a second common sending point for transmitting a second synchronization message to at least one node other than the first node on the second channel based on the second time difference; wherein the first common sending point and the second common sending point are calculated so that the first synchronization message is transmitted at approximately the same point in time as the second synchronization message. - View Dependent Claims (11, 12, 13)
-
Specification