METHOD OF TIMESTAMP SYNCHRONIZATION OF A RESERVATION-BASED TDMA PROTOCOL

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). The method includes the steps of sending a first command from the control node, at a first time, then storing a starting timestamp value in a register within the control node and each of the other nodes, in response to the first command, and then sending a second command from the control node, at a second time later than the first time. Each of the other nodes computes the difference between the starting timestamp value and a current timestamp value, and than adds the computed difference to the current timestamp value. In an alternative embodiment, the control node sends a preset command and each of the other nodes presets their respective timestamp to a prescribed initial timestamp value, in response to the preset command. Each of the nodes periodically compares a current timestamp counter value with a prescribed reset value, and upon detecting a coincidence, sets a sync flag latch to indicate that a next timestamp value correction is to be made, in response to a next preset command. Networks that implement the above-described methods are also disclosed.