摘要 |
A method for synchronizing timestamps in a network (e.g., a wireless ATM network) that includes a control node and a plurality of other nodes that communicate with one another over a common channel mediated by a medium-access control subsystem (e.g., one that uses a reservation-based TDMA protocol). At the control node, when a timestamp command is sent from MAC to PHY over the MAC-PHY interface, the current timestamp value at the control node is captured from the MAC-PHY interface. The captured timestamp value is then added by a timestamp update interval, T, and stored to become the timestamp value included in the next timestamp transmission exactly T seconds later. At each other node, when the timestamp command is received by PHY and sent to MAC over the MAC-PHY interface, the current timestamp value at the respective other node is captured from the MAC-PHY interface. The captured timestamp value is then compared with the timestamp value contained in the timestamp command and the difference, if any, is stored in an offset_register. This offset value will later be added to the timestamp counter in a non-time-critical manner under software control before the arrival of the next timestamp command.
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