Improve collaborative editing systems by time division multiple access synchronized with Ieee1588

Asynchronous distributed system is hard to realize time division multiplexing. In order to synchronize a distributed system, we introduce IEEE 1588 protocol. IEEE 1588 protocol is a precision time synchronization protocol which can synchronize time in sub-microsecond (10^-6 second) range for the purpose of realizing time division multiplexing. The performance of precision time synchronization is different for distinct layers of network. The lower layer has better performance of precision time synchronization but it is difficult to modify the hardware\´s clock. To achieve precision time synchronization, we can use a virtual clock for each ordinary clock in application layer. It is also a cheap method to realize precision time synchronization for achieving time division multiplexing. We introduce adaptive Kalman filter to predict the time offset in virtual clock, it can synchronize time in millisecond (10"³) range. An application of collaborative editing system enhanced by time division multiplexing is dividing a circuit diagram into several parts to access the PCB layout by several PCB layout engineers on internet. We need to update the layout diagram in real time. In order to reduce the collisions of transmission, improving the problem of synchronization gap becomes more important. The result of our simulation shows that each user has his own time slot and upload his data in his own time to avoid simultaneous changes conflicts by several clients.